Next Issue
Volume 11, June
Previous Issue
Volume 11, April

Nanomaterials, Volume 11, Issue 5 (May 2021) – 296 articles

Cover Story (view full-size image): Interest in nano-sized lipid vesicles relies on their use as mimics for endosomes or nanocarriers for drug delivery. The interactions between lipid vesicles and cell membranes involve spontaneous interbilayer lipid transfer by several mechanisms, such as monomer transfer or hemifusion. Here, we demonstrate the potential of QCM-D for detecting and quantifying lipid transfer between zwitterionic nanoscale-sized vesicles with high sensitivity and reduced amounts of biomolecules. The time-dependent changes in viscoelastic properties of the supported membrane layers during their main phase transition reveal that lipid transfer is asymmetric and unidirectional from shorter-chain lipid donor vesicles to longer-chain lipid acceptor vesicles. View this paper
  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
Order results
Result details
Select all
Export citation of selected articles as:
Article
Synthesis, Characterizations, and 9.4 Tesla T2 MR Images of Polyacrylic Acid-Coated Terbium(III) and Holmium(III) Oxide Nanoparticles
Nanomaterials 2021, 11(5), 1355; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051355 - 20 May 2021
Viewed by 673
Abstract
Polyacrylic acid (PAA)-coated lanthanide oxide (Ln2O3) nanoparticles (NPs) (Ln = Tb and Ho) with high colloidal stability and good biocompatibility were synthesized, characterized, and investigated as a new class of negative (T2) magnetic resonance imaging (MRI) contrast [...] Read more.
Polyacrylic acid (PAA)-coated lanthanide oxide (Ln2O3) nanoparticles (NPs) (Ln = Tb and Ho) with high colloidal stability and good biocompatibility were synthesized, characterized, and investigated as a new class of negative (T2) magnetic resonance imaging (MRI) contrast agents at high MR fields. Their r2 values were appreciable at a 3.0 T MR field and higher at a 9.4 T MR field, whereas their r1 values were negligible at all MR fields, indicating their exclusive induction of T2 relaxations with negligible induction of T1 relaxations. Their effectiveness as T2 MRI contrast agents at high MR fields was confirmed from strong negative contrast enhancements in in vivo T2 MR images at a 9.4 T MR field after intravenous administration into mice tails. Full article
(This article belongs to the Special Issue Nanomaterials as Contrast Agent for Bioimaging)
Show Figures

Figure 1

Article
Hyaluronic Acid-Based Nanocapsules as Efficient Delivery Systems of Garlic Oil Active Components with Anticancer Activity
Nanomaterials 2021, 11(5), 1354; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051354 - 20 May 2021
Viewed by 702
Abstract
Diallyl disulfide (DADS) and diallyl trisulfide (DATS) are garlic oil compounds exhibiting beneficial healthy properties including anticancer action. However, these compounds are sparingly water-soluble with a limited stability that may imply damage to blood vessels or cells after administration. Thus, their encapsulation in [...] Read more.
Diallyl disulfide (DADS) and diallyl trisulfide (DATS) are garlic oil compounds exhibiting beneficial healthy properties including anticancer action. However, these compounds are sparingly water-soluble with a limited stability that may imply damage to blood vessels or cells after administration. Thus, their encapsulation in the oil-core nanocapsules based on a derivative of hyaluronic acid was investigated here as a way of protecting against oxidation and undesired interactions with blood and digestive track components. The nuclear magnetic resonance (1H NMR) technique was used to follow the oxidation processes. It was proved that the shell of the capsule acts as a barrier limiting the sulfur oxidation, enhancing the stability of C=C bonds in DADS and DATS. Moreover, it was shown that the encapsulation inhibited the lysis of the red blood cell membrane (mainly for DADS) and interactions with serum or digestive track components. Importantly, the biological functions and anticancer activity of DADS and DATS were preserved after encapsulation. Additionally, the nanocapsule formulations affected the migration of neoplastic cells—a desirable preliminary observation concerning the inhibition of migration. The proposed route of administration of these garlic extract components would enable reaching their higher concentrations in blood, longer circulation in a bloodstream, and thus, imply a better therapeutic effect. Full article
(This article belongs to the Special Issue Nanoparticles from Natural Polymers: Synthesis and Applications)
Show Figures

Graphical abstract

Review
Recent Progress on the Characterization of Cellulose Nanomaterials by Nanoscale Infrared Spectroscopy
Nanomaterials 2021, 11(5), 1353; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051353 - 20 May 2021
Viewed by 551
Abstract
Researches of cellulose nanomaterials have seen nearly exponential growth over the past several decades for versatile applications. The characterization of nanostructural arrangement and local chemical distribution is critical to understand their role when developing cellulose materials. However, with the development of current characterization [...] Read more.
Researches of cellulose nanomaterials have seen nearly exponential growth over the past several decades for versatile applications. The characterization of nanostructural arrangement and local chemical distribution is critical to understand their role when developing cellulose materials. However, with the development of current characterization methods, the simultaneous morphological and chemical characterization of cellulose materials at nanoscale resolution is still challenging. Two fundamentally different nanoscale infrared spectroscopic techniques, namely atomic force microscope based infrared spectroscopy (AFM-IR) and infrared scattering scanning near field optical microscopy (IR s-SNOM), have been established by the integration of AFM with IR spectroscopy to realize nanoscale spatially resolved imaging for both morphological and chemical information. This review aims to summarize and highlight the recent developments in the applications of current state-of-the-art nanoscale IR spectroscopy and imaging to cellulose materials. It briefly outlines the basic principles of AFM-IR and IR s-SNOM, as well as their advantages and limitations to characterize cellulose materials. The uses of AFM-IR and IR s-SNOM for the understanding and development of cellulose materials, including cellulose nanomaterials, cellulose nanocomposites, and plant cell walls, are extensively summarized and discussed. The prospects of future developments in cellulose materials characterization are provided in the final part. Full article
Show Figures

Figure 1

Article
Photosensing and Characterizing of the Pristine and In-, Sn-Doped Bi2Se3 Nanoplatelets Fabricated by Thermal V–S Process
Nanomaterials 2021, 11(5), 1352; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051352 - 20 May 2021
Viewed by 504
Abstract
Pristine, and In-, Sn-, and (In, Sn)-doped Bi2Se3 nanoplatelets synthesized on Al2O3(100) substrate by a vapor–solid mechanism in thermal CVD process via at 600 °C under 2 × 10−2 Torr. XRD and HRTEM reveal that [...] Read more.
Pristine, and In-, Sn-, and (In, Sn)-doped Bi2Se3 nanoplatelets synthesized on Al2O3(100) substrate by a vapor–solid mechanism in thermal CVD process via at 600 °C under 2 × 10−2 Torr. XRD and HRTEM reveal that In or Sn dopants had no effect on the crystal structure of the synthesized rhombohedral-Bi2Se3. FPA–FTIR reveals that the optical bandgap of doped Bi2Se3 was 26.3%, 34.1%, and 43.7% lower than pristine Bi2Se3. XRD, FESEM–EDS, Raman spectroscopy, and XPS confirm defects (In3+Bi3+), (In3+V0), (Sn4+Bi3+), (V0Bi3+), and (Sn2+Bi3+). Photocurrent that was generated in (In,Sn)-doped Bi2Se3 under UV(8 W) and red (5 W) light revealed stable photocurrents of 5.20 × 10−10 and 0.35 × 10−10 A and high Iphoto/Idark ratios of 30.7 and 52.2. The rise and fall times of the photocurrent under UV light were 4.1 × 10−2 and 6.6 × 10−2 s. Under UV light, (In,Sn)-dopedBi2Se3 had 15.3% longer photocurrent decay time and 22.6% shorter rise time than pristine Bi2Se3, indicating that (In,Sn)-doped Bi2Se3 exhibited good surface conduction and greater photosensitivity. These results suggest that In, Sn, or both dopants enhance photodetection of pristine Bi2Se3 under UV and red light. The findings also suggest that type of defect is a more important factor than optical bandgap in determining photo-detection sensitivity. (In,Sn)-doped Bi2Se3 has greater potential than undoped Bi2Se3 for use in UV and red-light photodetectors. Full article
(This article belongs to the Special Issue Optoelectronic Properties and Applications of Nanomaterials)
Show Figures

Figure 1

Review
Behavior of Silicon Carbide Materials under Dry to Hydrothermal Conditions
Nanomaterials 2021, 11(5), 1351; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051351 - 20 May 2021
Viewed by 607
Abstract
Silicon carbide materials are excellent candidates for high-performance applications due to their outstanding thermomechanical properties and their strong corrosion resistance. SiC materials can be processed in various forms, from nanomaterials to continuous fibers. Common applications of SiC materials include the aerospace and nuclear [...] Read more.
Silicon carbide materials are excellent candidates for high-performance applications due to their outstanding thermomechanical properties and their strong corrosion resistance. SiC materials can be processed in various forms, from nanomaterials to continuous fibers. Common applications of SiC materials include the aerospace and nuclear fields, where the material is used in severely oxidative environments. Therefore, it is important to understand the kinetics of SiC oxidation and the parameters influencing them. The first part of this review focuses on the oxidation of SiC in dry air according to the Deal and Grove model showing that the oxidation behavior of SiC depends on the temperature and the time of oxidation. The oxidation rate can also be accelerated with the presence of H2O in the system due to its diffusion through the oxide scales. Therefore, wet oxidation is studied in the second part. The third part details the effect of hydrothermal media on the SiC materials that has been explained by different models, namely Yoshimura (1986), Hirayama (1989) and Allongue (1992). The last part of this review focuses on the hydrothermal corrosion of SiC materials from an application point of view and determine whether it is beneficial (manufacturing of materials) or detrimental (use of SiC in latest nuclear reactors). Full article
(This article belongs to the Special Issue Hydrothermal Synthesis of Nanoparticles)
Show Figures

Figure 1

Article
Electromagnetically Induced Transparency-Like Effect by Dark-Dark Mode Coupling
Nanomaterials 2021, 11(5), 1350; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051350 - 20 May 2021
Viewed by 593
Abstract
Electromagnetically induced transparency-like (EIT-like) effect is a promising research area for applications of slow light, sensing and metamaterials. The EIT-like effect is generally formed by the destructive interference of bright-dark mode coupling and bright-bright mode coupling. There are seldom reports about EIT-like effect [...] Read more.
Electromagnetically induced transparency-like (EIT-like) effect is a promising research area for applications of slow light, sensing and metamaterials. The EIT-like effect is generally formed by the destructive interference of bright-dark mode coupling and bright-bright mode coupling. There are seldom reports about EIT-like effect realized by the coupling of two dark modes. In this paper, we numerically and theoretically demonstrated that the EIT-like effect is achieved through dark-dark mode coupling of two waveguide resonances in a compound nanosystem with metal grating and multilayer structure. If we introduce |1, |2 and |3 to represent the surface plasmon polaritons (SPPs) resonance, waveguide resonance in layer 2, and waveguide resonance in layer 4, the destructive interference occurs between two pathways of |0|1|2 and |0|1|2|3|2, where |0 is the ground state without excitation. Our work will stimulate more studies on EIT-like effect with dark-dark mode coupling in other systems. Full article
(This article belongs to the Special Issue Nonlinear and Quantum Optics with Nanostructures)
Show Figures

Figure 1

Article
Modified Camellia oleifera Shell Carbon with Enhanced Performance for the Adsorption of Cooking Fumes
Nanomaterials 2021, 11(5), 1349; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051349 - 20 May 2021
Viewed by 571
Abstract
Using Camellia oleifera shell (COS) as a raw material and phosphoric acid as the activator, activated Camellia oleifera shell carbon (COSC-0) was prepared and then modified by Fenton’s reagent (named as COSC-1). SEM, GC-MS, FTIR, and specific surface area and pore analyzers were [...] Read more.
Using Camellia oleifera shell (COS) as a raw material and phosphoric acid as the activator, activated Camellia oleifera shell carbon (COSC-0) was prepared and then modified by Fenton’s reagent (named as COSC-1). SEM, GC-MS, FTIR, and specific surface area and pore analyzers were used to study the adsorption performance of COS, COSC-0, and COSC-1 on cooking fumes. Results showed that COSC-1 was the best adsorbent compared with COS and COSC-0. The adsorption quantity and penetrating time of COSC-1 were 44.04 mg/g and 4.1 h, respectively. Most aldehydes could be adsorbed by COSC-1, which was due to the large number of carbonyl and carboxyl groups generated on the surface of COSC-1 from the action of Fenton’s reagent. The adsorption effect of COSC-1 on different types of pollutants in cooking fumes was analyzed based on the similar compatibility principle. COSC-1 showed a much higher adsorption effect on the strong polarity functional groups than on weak polar groups. The results provide a theoretical basis for the application of Camellia oleifera shell carbon adsorption technology in the treatment of cooking fumes. Full article
(This article belongs to the Section Environmental Nanoscience and Nanotechnology)
Show Figures

Graphical abstract

Article
Deep-Ultraviolet Transparent Conductive MWCNT/SiO2 Composite Thin Film Fabricated by UV Irradiation at Ambient Temperature onto Spin-Coated Molecular Precursor Film
Nanomaterials 2021, 11(5), 1348; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051348 - 20 May 2021
Viewed by 521
Abstract
Deep-ultraviolet (DUV) light-transparent conductive composite thin films, consisting of dispersed multiwalled carbon nanotubes (MWCNTs) and SiO2 matrix composites, were fabricated on a quartz glass substrate. Transparent and well-adhered amorphous thin films, with a thickness of 220 nm, were obtained by weak ultraviolet [...] Read more.
Deep-ultraviolet (DUV) light-transparent conductive composite thin films, consisting of dispersed multiwalled carbon nanotubes (MWCNTs) and SiO2 matrix composites, were fabricated on a quartz glass substrate. Transparent and well-adhered amorphous thin films, with a thickness of 220 nm, were obtained by weak ultraviolet (UV) irradiation (4 mW cm−2 at 254 nm) for more than 6 h at 20−40 °C onto the precursor films, which were obtained by spin coating with a mixed solution of MWCNT in water and Si(IV) complex in ethanol. The electrical resistivity of MWCNT/SiO2 composite thin film is 0.7 Ω·cm, and transmittance in the wavelength region from DUV to visible light is higher than 80%. The MWCNT/SiO2 composite thin film showed scratch resistance at pencil hardness of 8H. Importantly, the resistivity of the MWCNT/SiO2 composite thin film was maintained at the original level even after heat treatment at 500 °C for 1 h. It was observed that the heat treatment of the composite thin film improved durability against both aqueous solutions involving a strong acid (HCl) and a strong base (NaOH). Full article
(This article belongs to the Special Issue Research of Carbon Nanomaterials and Nanocomposites)
Show Figures

Figure 1

Article
Controllable One-Step Synthesis of Mixed-Phase TiO2 Nanocrystals with Equivalent Anatase/Rutile Ratio for Enhanced Photocatalytic Performance
Nanomaterials 2021, 11(5), 1347; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051347 - 20 May 2021
Viewed by 601
Abstract
In this study, the novel mixed-phase TiO2 nanocrystals (s-TiO2) with nearly equivalent anatase/rutile ratio were fabricated in the reagent of sec-butanol at the relatively low temperature of 80 °C by using a facile one-step condensing reflux method. The photocatalytic water [...] Read more.
In this study, the novel mixed-phase TiO2 nanocrystals (s-TiO2) with nearly equivalent anatase/rutile ratio were fabricated in the reagent of sec-butanol at the relatively low temperature of 80 °C by using a facile one-step condensing reflux method. The photocatalytic water splitting hydrogen production performance of s-TiO2 nanocrystals is close to that of commercial TiO2 (P25), and its photocatalytic degradation performance is about four times that of P25. The energy-level staggered interfaces and surface bridged hydroxyl groups significantly increased due to the anatase/rutile mixed-phase crystal structure and high specific surface area, which might generate the synergistic effect for the improvement of photocatalytic degradation. Full article
Show Figures

Figure 1

Article
A New Method for Dispersing Pristine Carbon Nanotubes Using Regularly Arranged S-Layer Proteins
Nanomaterials 2021, 11(5), 1346; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051346 - 20 May 2021
Viewed by 517
Abstract
Homogeneous and stable dispersions of functionalized carbon nanotubes (CNTs) in aqueous solutions are imperative for a wide range of applications, especially in life and medical sciences. Various covalent and non-covalent approaches were published to separate the bundles into individual tubes. In this context, [...] Read more.
Homogeneous and stable dispersions of functionalized carbon nanotubes (CNTs) in aqueous solutions are imperative for a wide range of applications, especially in life and medical sciences. Various covalent and non-covalent approaches were published to separate the bundles into individual tubes. In this context, this work demonstrates the non-covalent modification and dispersion of pristine multi-walled carbon nanotubes (MWNTs) using two S-layer proteins, namely, SbpA from Lysinibacillus sphaericus CCM2177 and SbsB from Geobacillus stearothermophilus PV72/p2. Both the S-layer proteins coated the MWNTs completely. Furthermore, it was shown that SbpA can form caps at the ends of MWNTs. Reassembly experiments involving a mixture of both S-layer proteins in the same solution showed that the MWNTs were primarily coated with SbsB, whereas SbpA formed self-assembled layers. The dispersibility of the pristine nanotubes coated with SbpA was determined by zeta potential measurements (−24.4 +/− 0.6 mV, pH = 7). Finally, the SbpA-coated MWNTs were silicified with tetramethoxysilane (TMOS) using a mild biogenic approach. As expected, the thickness of the silica layer could be controlled by the reaction time and was 6.3 +/− 1.25 nm after 5 min and 25.0 +/− 5.9 nm after 15 min. Since S-layer proteins have already demonstrated their capability to bind (bio)molecules in dense packing or to act as catalytic sites in biomineralization processes, the successful coating of pristine MWNTs has great potential in the development of new materials, such as biosensor architectures. Full article
(This article belongs to the Special Issue Growth, Characterization and Applications of Nanotubes)
Show Figures

Graphical abstract

Article
Calcium Alginate Beads with Entrapped Iron Oxide Magnetic Nanoparticles Functionalized with Methionine—A Versatile Adsorbent for Arsenic Removal
Nanomaterials 2021, 11(5), 1345; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051345 - 20 May 2021
Viewed by 537
Abstract
A novel beads adsorbent, consisting of calcium alginate entrapped on magnetic nanoparticles functionalized with methionine (MFMNABs), was developed for effective elimination of arsenic from water. The material was characterized by FT-IR (Fourier Transform Infrared Spectroscopy), SEM (Scanning Electron Microscopic), XRD (X-ray Diffraction) and [...] Read more.
A novel beads adsorbent, consisting of calcium alginate entrapped on magnetic nanoparticles functionalized with methionine (MFMNABs), was developed for effective elimination of arsenic from water. The material was characterized by FT-IR (Fourier Transform Infrared Spectroscopy), SEM (Scanning Electron Microscopic), XRD (X-ray Diffraction) and TEM (Transmission Electron Microscopy). The arsenic removal capacity of the material was studied by altering variables such as pH of the solution, contact time, adsorbent dose and adsorbate concentration. The maximal removal of As(III) was 99.56% under optimal conditions with an equilibrium time of 110 min and pH 7.0–7.5. The adsorption followed a second order kinetics and data best fitted the Langmuir isotherm with a correlation coefficient of R2 = 0.9890 and adsorption capacity (qm) of 6.6533 mg/g. The thermodynamic study showed entropy change (∆S) and enthalpy change (∆H) to be 34.32 J mol−1 K and 5.25 kJ mol−1, respectively. This study proved that it was feasible to treat an As(III) solution with MFMNABs. The synthesized adsorbent was cost-effective, environmentally friendly and versatile, compared to other adsorbents. The adsorption study was carried by low cost spectrophotometric method using N- bromosuccinimide and rhodamine-B developed in our laboratory. Full article
Show Figures

Figure 1

Article
Molecular Dynamics Simulation for the Effect of Fluorinated Graphene Oxide Layer Spacing on the Thermal and Mechanical Properties of Fluorinated Epoxy Resin
Nanomaterials 2021, 11(5), 1344; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051344 - 20 May 2021
Viewed by 551
Abstract
Traditional epoxy resin (EP) materials have difficulty to meet the performance requirements in the increasingly complex operating environment of the electrical and electronic industry. Therefore, it is necessary to study the design and development of new epoxy composites. At present, fluorinated epoxy resin [...] Read more.
Traditional epoxy resin (EP) materials have difficulty to meet the performance requirements in the increasingly complex operating environment of the electrical and electronic industry. Therefore, it is necessary to study the design and development of new epoxy composites. At present, fluorinated epoxy resin (F-EP) is widely used, but its thermal and mechanical properties cannot meet the demand. In this paper, fluorinated epoxy resin was modified by ordered filling of fluorinated graphene oxide (FGO). The effect of FGO interlayer spacing on the thermal and mechanical properties of the composite was studied by molecular dynamics (MD) simulation. It is found that FGO with ordered filling can significantly improve the thermal and mechanical properties of F-EP, and the modification effect is better than that of FGO with disordered filling. When the interlayer spacing of FGO is about 9 Å, the elastic modulus, glass transition temperature, thermal expansion coefficient, and thermal conductivity of FGO are improved with best effect. Furthermore, we calculated the micro parameters of different systems, and analyzed the influencing mechanism of ordered filling and FGO layer spacing on the properties of F-EP. It is considered that FGO can bind the F-EP molecules on both sides of the nanosheets, reducing the movement ability of the molecular segments of the materials, so as to achieve the enhancement effect. The results can provide new ideas for the development of high-performance epoxy nanocomposites. Full article
(This article belongs to the Special Issue Advanced Mechanical Modeling of Nanomaterials and Nanostructures)
Show Figures

Graphical abstract

Article
The Antimicrobial and Anti-Inflammatory Effects of Silver Nanoparticles Synthesised from Cotyledon orbiculata Aqueous Extract
Nanomaterials 2021, 11(5), 1343; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051343 - 20 May 2021
Cited by 1 | Viewed by 617
Abstract
Cotyledon orbiculata, commonly known as pig’s ear, is an important medicinal plant of South Africa. It is used in traditional medicine to treat many ailments, including skin eruptions, abscesses, inflammation, boils and acne. Many plants have been used to synthesize metallic nanoparticles, [...] Read more.
Cotyledon orbiculata, commonly known as pig’s ear, is an important medicinal plant of South Africa. It is used in traditional medicine to treat many ailments, including skin eruptions, abscesses, inflammation, boils and acne. Many plants have been used to synthesize metallic nanoparticles, particularly silver nanoparticles (AgNPs). However, the synthesis of AgNPs from C. orbiculata has never been reported before. The aim of this study was to synthesize AgNPs using C. orbiculata and evaluate their antimicrobial and immunomodulatory properties. AgNPs were synthesized and characterized using Ultraviolet-Visible Spectroscopy (UV-Vis), Dynamic Light Scattering (DLS) and High-Resolution Transmission Electron Microscopy (HR-TEM). The antimicrobial activities of the nanoparticles against skin pathogens (Staphylococcus aureus, Staphylococcus epidermidis, Methicillin Resistance Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans) as well as their effects on cytokine production in macrophages (differentiated from THP-1 cells) were evaluated. The AgNPs from C. orbiculata exhibited antimicrobial activity, with the highest activity observed against P. aeruginosa (5 µg/mL). The AgNPs also showed anti-inflammatory activity by inhibiting the secretion of pro-inflammatory cytokines (TNF-alpha, IL-6 and IL-1 beta) in lipopolysaccharide-treated macrophages. This concludes that the AgNPs produced from C. orbiculata possess antimicrobial and anti-inflammation properties. Full article
Show Figures

Figure 1

Article
Femtosecond Laser-Processing of Pre-Anodized Ti-Based Bone Implants for Cell-Repellent Functionalization
Nanomaterials 2021, 11(5), 1342; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051342 - 20 May 2021
Viewed by 581
Abstract
Microstructures and nanostructures can be used to reduce the adhesion of the cells on the auxiliary material. Therefore, the aim of our work was to fabricate laser-induced hierarchical microstructures and nanostructures by femtosecond laser-treatment (wavelength 1040 nm, pulse length 350 fs, repetition rates [...] Read more.
Microstructures and nanostructures can be used to reduce the adhesion of the cells on the auxiliary material. Therefore, the aim of our work was to fabricate laser-induced hierarchical microstructures and nanostructures by femtosecond laser-treatment (wavelength 1040 nm, pulse length 350 fs, repetition rates in the kHz range) to reduce the cell adhesion. Additionally, surface chemistry modification by optimized electrochemical anodization was used to further reduce the cell adhesion. For testing, flat plates and bone screws made of Ti-6Al-4V were used. Bone-forming cells (human osteoblasts from the cell line SAOS-2) were grown on the bone implants and additional test samples for two to three weeks. After the growth period, the cells were characterized by scanning electron microscopy (SEM). While earlier experiments with fibroblasts had shown that femtosecond laser-processing followed by electrochemical anodization had a significant impact on cell adhesion reduction, for osteoblasts the same conditions resulted in an activation of the cells with increased production of extracellular matrix material. Significant reduction of cell adhesion for osteoblasts was only obtained at pre-anodized surfaces. It could be demonstrated that this functionalization by means of femtosecond laser-processing can result in bone screws that hinder the adhesion of osteoblasts. Full article
(This article belongs to the Special Issue Nanopatterning of Bionic Materials)
Show Figures

Figure 1

Article
Cold Plasma Preparation of Pd/Graphene Catalyst for Reduction of p-Nitrophenol
Nanomaterials 2021, 11(5), 1341; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051341 - 20 May 2021
Viewed by 521
Abstract
Supported metal nanoparticles with small size and high dispersion can improve the performance of heterogeneous catalysts. To prepare graphene-supported Pd catalysts, graphene and PdCl2 were used as support and Pd precursors, respectively. Pd/G-P and Pd/G-H catalysts were prepared by cold plasma and [...] Read more.
Supported metal nanoparticles with small size and high dispersion can improve the performance of heterogeneous catalysts. To prepare graphene-supported Pd catalysts, graphene and PdCl2 were used as support and Pd precursors, respectively. Pd/G-P and Pd/G-H catalysts were prepared by cold plasma and conventional thermal reduction, respectively, for the catalytic reduction of p-nitrophenol (4-NP). The reaction followed quasi-first-order kinetics, and the apparent rate constant of Pd/G-P and Pd/G-H was 0.0111 and 0.0042 s−1, respectively. The graphene support was exfoliated by thermal reduction and cold plasma, which benefits the 4-NP adsorption. Pd/G-P presented a higher performance because cold plasma promoted the migration of Pd species to the support outer surface. The Pd/C atomic ratio for Pd/G-P and Pd/G-H was 0.014 and 0.010, respectively. In addition, the Pd nanoparticles in Pd/G-P were smaller than those in Pd/G-H, which was beneficial for the catalytic reduction. The Pd/G-P sample presented abundant oxygen-containing functional groups, which anchored the metal nanoparticles and enhanced the metal-support interaction. This was further confirmed by the shift in the binding energy to a high value for Pd3d in Pd/G-P. The cold plasma method operated under atmospheric pressure is effective for the preparation of Pd/G catalysts with enhanced catalytic activity for 4-NP reduction. Full article
Show Figures

Figure 1

Article
Hydrous Hydrazine Decomposition for Hydrogen Production Using of Ir/CeO2: Effect of Reaction Parameters on the Activity
Nanomaterials 2021, 11(5), 1340; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051340 - 19 May 2021
Viewed by 535
Abstract
In the present work, an Ir/CeO2 catalyst was prepared by the deposition–precipitation method and tested in the decomposition of hydrazine hydrate to hydrogen, which is very important in the development of hydrogen storage materials for fuel cells. The catalyst was characterised using [...] Read more.
In the present work, an Ir/CeO2 catalyst was prepared by the deposition–precipitation method and tested in the decomposition of hydrazine hydrate to hydrogen, which is very important in the development of hydrogen storage materials for fuel cells. The catalyst was characterised using different techniques, i.e., X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) equipped with X-ray detector (EDX) and inductively coupled plasma—mass spectroscopy (ICP-MS). The effect of reaction conditions on the activity and selectivity of the material was evaluated in this study, modifying parameters such as temperature, the mass of the catalyst, stirring speed and concentration of base in order to find the optimal conditions of reaction, which allow performing the test in a kinetically limited regime. Full article
(This article belongs to the Section Energy and Catalysis)
Show Figures

Figure 1

Article
Cytotoxic Effect of Graphene Oxide Nanoribbons on Escherichia coli
Nanomaterials 2021, 11(5), 1339; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051339 - 19 May 2021
Viewed by 564
Abstract
The biological and environmental toxicity of graphene and graphene derivatives have attracted great research interest due to their increasing applications. However, the cytotoxic mechanism is poorly understood. Here, we investigated the cytotoxic effect of graphene oxide nanoribbons (GORs) on Escherichia coli (E. [...] Read more.
The biological and environmental toxicity of graphene and graphene derivatives have attracted great research interest due to their increasing applications. However, the cytotoxic mechanism is poorly understood. Here, we investigated the cytotoxic effect of graphene oxide nanoribbons (GORs) on Escherichia coli (E. coli) in an in vitro method. The fabricated GORs formed long ribbons, 200 nm wide. Based on the results of the MTT assay and plate-culture experiments, GORs significantly inhibited the growth and reproduction of E. coli in a concentration-dependent manner. We found that GORs stimulated E. coli to secrete reactive oxygen species, which then oxidized and damaged the bacterial cell membrane. Moreover, interaction between GORs and E. coli cytomembrane resulted in polysaccharide adsorption by GORs and the release of lactic dehydrogenase. Furthermore, GORs effectively depleted the metal ions as nutrients in the culture medium by adsorption. Notably, mechanical cutting by GORs was not obvious, which is quite different from the case of graphene oxide sheets to E. coli. Full article
Show Figures

Figure 1

Article
Synthesis of Mesoporous Silica Coated Gold Nanorods Loaded with Methylene Blue and Its Potentials in Antibacterial Applications
Nanomaterials 2021, 11(5), 1338; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051338 - 19 May 2021
Cited by 1 | Viewed by 614
Abstract
In this work, the successful preparation and characterization of gold nanorods (AuNRs) coated with a mesoporous silica shell ([email protected]) was achieved. Conjugation with methylene blue (MB) as a model drug using ultrasound-stimulated loading has been explored for further application in light-mediated antibacterial studies. [...] Read more.
In this work, the successful preparation and characterization of gold nanorods (AuNRs) coated with a mesoporous silica shell ([email protected]) was achieved. Conjugation with methylene blue (MB) as a model drug using ultrasound-stimulated loading has been explored for further application in light-mediated antibacterial studies. Lyophilization of this conjugated nanosystem was analyzed using trehalose (TRH) as a cryogenic protector. The obtained stable dry formulation shows potent antimicrobial activity against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria after a simple post-treatment irradiation method with a red laser during a short time period. Full article
(This article belongs to the Special Issue Design, Development, and Production of Nanocarriers and Nanovehicles)
Show Figures

Graphical abstract

Article
SERRS Detection on Silver Nanoparticles Supported on Acid-Treated Melamine-Resin Microspheres
Nanomaterials 2021, 11(5), 1337; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051337 - 19 May 2021
Viewed by 491
Abstract
Melamine-resin microspheres were synthesized at a pH of 4.0 for 20 min and used as silver nanoparticle (AgNP) carriers for surface enhanced resonant Raman scattering (SERRS) detection. An acetic acid–treatment reaction was introduced into the fabrication of the final substrate. The SERRS performance [...] Read more.
Melamine-resin microspheres were synthesized at a pH of 4.0 for 20 min and used as silver nanoparticle (AgNP) carriers for surface enhanced resonant Raman scattering (SERRS) detection. An acetic acid–treatment reaction was introduced into the fabrication of the final substrate. The SERRS performance of the substrate was effectively optimized by regulating excess formaldehyde and experimental parameters, such as acidity, number of treatments and reaction temperature in the acid-treatment reaction. Based on the SERRS detection, it was declared that a trace amount of oligomers with a certain degree of polymerization is necessary for the construction of SERRS hotspots. In addition, it is important to remove excess oligomers with reference to the synthetic reaction of the polymer materials, given the special role of oligomers and the wide application of polymer materials in SERRS detection. Full article
Show Figures

Figure 1

Review
Lignin Nanoparticles and Their Nanocomposites
Nanomaterials 2021, 11(5), 1336; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051336 - 19 May 2021
Viewed by 754
Abstract
Lignin nanomaterials have emerged as a promising alternative to fossil-based chemicals and products for some potential added-value applications, which benefits from their structural diversity and biodegradability. This review elucidates a perspective in recent research on nanolignins and their nanocomposites. It summarizes the different [...] Read more.
Lignin nanomaterials have emerged as a promising alternative to fossil-based chemicals and products for some potential added-value applications, which benefits from their structural diversity and biodegradability. This review elucidates a perspective in recent research on nanolignins and their nanocomposites. It summarizes the different nanolignin preparation methods, emphasizing anti-solvent precipitation, self-assembly and interfacial crosslinking. Also described are the preparation of various nanocomposites by the chemical modification of nanolignin and compounds with inorganic materials or polymers. Additionally, advances in numerous potential high-value applications, such as use in food packaging, biomedical, chemical engineering and biorefineries, are described. Full article
(This article belongs to the Special Issue Nanoparticles from Natural Polymers: Synthesis and Applications)
Show Figures

Figure 1

Article
Sieve-Like CNT Film Coupled with TiO2 Nanowire for High-Performance Continuous-Flow Photodegradation of Rhodamine B under Visible Light Irradiation
Nanomaterials 2021, 11(5), 1335; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051335 - 19 May 2021
Viewed by 549
Abstract
Continuous-flow photoreactors hold great promise for the highly efficient photodegradation of pollutants due to their continuity and sustainability. However, how to enable a continuous-flow photoreactor with the combined features of high photodegradation efficiency and durability as well as broad-wavelength light absorption and large-scale [...] Read more.
Continuous-flow photoreactors hold great promise for the highly efficient photodegradation of pollutants due to their continuity and sustainability. However, how to enable a continuous-flow photoreactor with the combined features of high photodegradation efficiency and durability as well as broad-wavelength light absorption and large-scale processing remains a significant challenge. Herein, we demonstrate a facile and effective strategy to construct a sieve-like carbon nanotube (CNT)/TiO2 nanowire film (SCTF) with superior flexibility (180° bending), high tensile strength (75–82 MPa), good surface wettability, essential light penetration and convenient visible light absorption. Significantly, the unique architecture, featuring abundant, well-ordered and uniform mesopores with ca. 70 µm in diameter, as well as a homogenous distribution of TiO2 nanowires with an average diameter of ca. 500 nm, could act as a “waterway” for efficient solution infiltration through the SCTF, thereby, enabling the photocatalytic degradation of polluted water in a continuous-flow mode. The optimized SCTF-2.5 displayed favorable photocatalytic behavior with 96% degradation of rhodamine B (RhB) within 80 min and a rate constant of 0.0394 min−1. The continuous-flow photodegradation device made using SCTF-2.5 featured exceptional photocatalytic behavior for the continuous degradation of RhB under simulated solar irradiation with a high degradation ratio (99.6%) and long-term stability (99.2% retention after working continuously for 72 h). This work sheds light on new strategies for designing and fabricating high-performance continuous-flow photoreactors toward future uses. Full article
Show Figures

Figure 1

Article
Optimization Method of the Solvothermal Parameters Using Box–Behnken Experimental Design—The Case Study of ZnO Structural and Catalytic Tailoring
Nanomaterials 2021, 11(5), 1334; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051334 - 19 May 2021
Viewed by 455
Abstract
ZnO photocatalysts were synthesized via solvothermal method and a reduced experimental design (Box–Behnken) was applied to investigate the influence of four parameters (temperature, duration, composition of the reaction mixture) upon the photocatalytic activity and the crystal structure of ZnO. The four parameters were [...] Read more.
ZnO photocatalysts were synthesized via solvothermal method and a reduced experimental design (Box–Behnken) was applied to investigate the influence of four parameters (temperature, duration, composition of the reaction mixture) upon the photocatalytic activity and the crystal structure of ZnO. The four parameters were correlated with photocatalytic degradation of methyl orange and the ratio of two crystallographic facets ((002) and (100)) using a quadratic model. The quadratic model shows good fit for both responses. The optimization experimental results validated the models. The ratio of the crystal facets shows similar variation as the photocatalytic activity of the samples. The water content of the solvent is the primary factor, which predominantly influence both responses. An explanation was proposed for the effect of the parameters and how the ratio of (002) and (100) crystal facets is influenced and its relation to the photocatalytic activity. The present research laconically describes a case study for an original experimental work, in order to serve as guideline to deal with such complicated subjects as quantifying influence of synthesis parameters upon the catalytic activity of the obtained ZnO. Full article
(This article belongs to the Special Issue Latest Developments in Photocatalytic Materials and Processes)
Show Figures

Graphical abstract

Article
Directional Plasmonic Excitation by Helical Nanotips
Nanomaterials 2021, 11(5), 1333; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051333 - 19 May 2021
Cited by 1 | Viewed by 526
Abstract
The phenomenon of coupling between light and surface plasmon polaritons requires specific momentum matching conditions. In the case of a single scattering object on a metallic surface, such as a nanoparticle or a nanohole, the coupling between a broadband effect, i.e., scattering, and [...] Read more.
The phenomenon of coupling between light and surface plasmon polaritons requires specific momentum matching conditions. In the case of a single scattering object on a metallic surface, such as a nanoparticle or a nanohole, the coupling between a broadband effect, i.e., scattering, and a discrete one, such as surface plasmon excitation, leads to Fano-like resonance lineshapes. The necessary phase matching requirements can be used to engineer the light–plasmon coupling and to achieve a directional plasmonic excitation. Here, we investigate this effect by using a chiral nanotip to excite surface plasmons with a strong spin-dependent azimuthal variation. This effect can be described by a Fano-like interference with a complex coupling factor that can be modified thanks to a symmetry breaking of the nanostructure. Full article
Show Figures

Graphical abstract

Review
Strategies to Build Hybrid Protein–DNA Nanostructures
Nanomaterials 2021, 11(5), 1332; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051332 - 18 May 2021
Viewed by 577
Abstract
Proteins and DNA exhibit key physical chemical properties that make them advantageous for building nanostructures with outstanding features. Both DNA and protein nanotechnology have growth notably and proved to be fertile disciplines. The combination of both types of nanotechnologies is helpful to overcome [...] Read more.
Proteins and DNA exhibit key physical chemical properties that make them advantageous for building nanostructures with outstanding features. Both DNA and protein nanotechnology have growth notably and proved to be fertile disciplines. The combination of both types of nanotechnologies is helpful to overcome the individual weaknesses and limitations of each one, paving the way for the continuing diversification of structural nanotechnologies. Recent studies have implemented a synergistic combination of both biomolecules to assemble unique and sophisticate protein–DNA nanostructures. These hybrid nanostructures are highly programmable and display remarkable features that create new opportunities to build on the nanoscale. This review focuses on the strategies deployed to create hybrid protein–DNA nanostructures. Here, we discuss strategies such as polymerization, spatial directing and organizing, coating, and rigidizing or folding DNA into particular shapes or moving parts. The enrichment of structural DNA nanotechnology by incorporating protein nanotechnology has been clearly demonstrated and still shows a large potential to create useful and advanced materials with cell-like properties or dynamic systems. It can be expected that structural protein–DNA nanotechnology will open new avenues in the fabrication of nanoassemblies with unique functional applications and enrich the toolbox of bionanotechnology. Full article
(This article belongs to the Special Issue The Application of DNA Nanotechnology)
Show Figures

Figure 1

Review
Recent Advances in the Development of Smart and Active Biodegradable Packaging Materials
Nanomaterials 2021, 11(5), 1331; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051331 - 18 May 2021
Cited by 1 | Viewed by 785
Abstract
Interest in the development of smart and active biodegradable packaging materials is increasing as food manufacturers try to improve the sustainability and environmental impact of their products, while still maintaining their quality and safety. Active packaging materials contain components that enhance their functionality, [...] Read more.
Interest in the development of smart and active biodegradable packaging materials is increasing as food manufacturers try to improve the sustainability and environmental impact of their products, while still maintaining their quality and safety. Active packaging materials contain components that enhance their functionality, such as antimicrobials, antioxidants, light blockers, or oxygen barriers. Smart packaging materials contain sensing components that provide an indication of changes in food attributes, such as alterations in their quality, maturity, or safety. For instance, a smart sensor may give a measurable color change in response to a deterioration in food quality. This article reviews recent advances in the development of active and smart biodegradable packaging materials in the food industry. Moreover, studies on the application of these packaging materials to monitor the freshness and safety of food products are reviewed, including dairy, meat, fish, fruit and vegetable products. Finally, the potential challenges associated with the application of these eco-friendly packaging materials in the food industry are discussed, as well as potential future directions. Full article
(This article belongs to the Special Issue Food Packaging Bionanocomposites)
Show Figures

Figure 1

Article
Cytokine-Mediated Inflammation in the Oral Cavity and Its Effect on Lipid Nanocarriers
Nanomaterials 2021, 11(5), 1330; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051330 - 18 May 2021
Viewed by 507
Abstract
Topical drug administration to the oral mucosa proves to be a promising treatment alternative for inflammatory diseases. However, disease-related changes in the cell barrier must be considered when developing such delivery systems. This study aimed at investigating the changes in the lining mucosa [...] Read more.
Topical drug administration to the oral mucosa proves to be a promising treatment alternative for inflammatory diseases. However, disease-related changes in the cell barrier must be considered when developing such delivery systems. This study aimed at investigating the changes in the lining mucosa caused by inflammation and evaluating the consequences on drug delivery systems such as nanostructured lipid carriers (NLC). For this, TR146 cells were treated with inflammatory cytokines and bacterial components. Cell viability and integrity, reactive oxygen species (ROS), and interleukin (IL)-8 release were used as endpoints to assess inflammation. Translocation of phosphatidylserine, cytoskeletal arrangement, opening of desmosomes, and cell proliferation were examined. Transport studies with NLC were performed considering active and passive pathways. The results showed that IL-1ß and tumor necrosis factor α induced inflammation by increasing IL-8 and ROS production (22-fold and 2-fold). Morphologically, loss of cell–cell connections and formation of stress fibers and hyperplasia were observed. The charge of the cell membrane shifted from neutral to negative, which increased the absorption of NLC due to the repulsive interactions between the hydrophobic negative particles and the cell membrane on the one hand, and interactions with lipophilic membrane proteins such as caveolin on the other. Full article
(This article belongs to the Special Issue Nanomedicine in Drug Delivery)
Show Figures

Graphical abstract

Article
Dimethylglyoxime Clathrate as Ligand Derived Nitrogen-Doped Carbon-Supported Nano-Metal Particles as Catalysts for Oxygen Reduction Reaction
Nanomaterials 2021, 11(5), 1329; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051329 - 18 May 2021
Viewed by 459
Abstract
Nitrogen-doped carbon-supported metal nano-particles show great promise as high-performance catalysts for novel energies, organic synthesis, environmental protection, and other fields. The synergistic effect between nitrogen-doped carbon and metal nano-particles enhances the catalytic properties. Thus, how to effectively combine nitrogen-doped carbon with metal nano-particles [...] Read more.
Nitrogen-doped carbon-supported metal nano-particles show great promise as high-performance catalysts for novel energies, organic synthesis, environmental protection, and other fields. The synergistic effect between nitrogen-doped carbon and metal nano-particles enhances the catalytic properties. Thus, how to effectively combine nitrogen-doped carbon with metal nano-particles is a crucial factor for the synthesis of novel catalysts. In this paper, we report on a facile method to prepare nitrogen-doped carbon-supported metal nano-particles by using dimethylgly-oxime as ligand. The nano-particles of Pd, Ni, Cu, and Fe were successfully prepared by the pyrolysis of the corresponding clathrate of ions and dimethylglyoxime. The ligand of dimethylglyoxime is adopted as the source for the nitrogen-doped carbon. The nano-structure of the prepared Pd, Ni, Cu, and Fe particles are confirmed by X-ray diffraction, scanning electron microscopy, and trans-mission electron microscopy tests. The catalytic performances of the obtained metal nano-particles for oxygen reduction reaction (ORR) are investigated by cyclic voltammetry, Tafel, linear sweeping voltammetry, rotating disc electrode, rotating ring disc electrode, and other technologies. Results show that the nitrogen-doped carbon-supported metal nano-particles can be highly efficient catalysts for ORR. The results of the paper exhibit a facile methodology to prepare nitrogen-doped carbon-supported metal nano-particles. Full article
(This article belongs to the Topic Nanomaterials for Sustainable Energy Applications)
Show Figures

Graphical abstract

Perspective
Unveiling the Potential Role of Nanozymes in Combating the COVID-19 Outbreak
Nanomaterials 2021, 11(5), 1328; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051328 - 18 May 2021
Viewed by 885
Abstract
The current coronavirus disease 2019 (COVID-19) outbreak is considered as one of the biggest public health challenges and medical emergencies of the century. A global health emergency demands an urgent development of rapid diagnostic tools and advanced therapeutics for the mitigation of COVID-19. [...] Read more.
The current coronavirus disease 2019 (COVID-19) outbreak is considered as one of the biggest public health challenges and medical emergencies of the century. A global health emergency demands an urgent development of rapid diagnostic tools and advanced therapeutics for the mitigation of COVID-19. To cope with the current crisis, nanotechnology offers a number of approaches based on abundance and versatile functioning. Despite major developments in early diagnostics and control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is still a need to find effective nanomaterials with low cost, high stability and easy use. Nanozymes are nanomaterials with innate enzyme-like characteristics and exhibit great potential for various biomedical applications such as disease diagnosis and anti-viral agents. Overall the potential and contribution of nanozymes in the fight against SARS-CoV-2 infection i.e., rapid detection, inhibition of the virus at various stages, and effective vaccine development strategies, is not fully explored. This paper discusses the utility and potential of nanozymes from the perspective of COVID-19. Moreover, future research directions and potential applications of nanozymes are highlighted to overcome the challenges related to early diagnosis and therapeutics development for the SARS-CoV-2. We anticipate the current perspective will play an effective role in the existing response to the COVID-19 crisis. Full article
Show Figures

Graphical abstract

Article
Spatiotemporal Visualization of Insecticides and Fungicides within Fruits and Vegetables Using Gold Nanoparticle-Immersed Paper Imprinting Mass Spectrometry Imaging
Nanomaterials 2021, 11(5), 1327; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051327 - 18 May 2021
Viewed by 560
Abstract
Food safety issues caused by pesticide residue have exerted far-reaching impacts on human daily life, yet the available detection methods normally focus on surface residue rather than pesticide penetration to the internal area of foods. Herein, we demonstrated gold nanoparticle (AuNP)-immersed paper imprinting [...] Read more.
Food safety issues caused by pesticide residue have exerted far-reaching impacts on human daily life, yet the available detection methods normally focus on surface residue rather than pesticide penetration to the internal area of foods. Herein, we demonstrated gold nanoparticle (AuNP)-immersed paper imprinting mass spectrometry imaging (MSI) for monitoring pesticide migration behaviors in various fruits and vegetables (i.e., apple, cucumber, pepper, plum, carrot, and strawberry). By manually stamping food tissues onto AuNP-immersed paper, this method affords the spatiotemporal visualization of insecticides and fungicides within fruits and vegetables, avoiding tedious and time-consuming sample preparation. Using the established MSI platform, we can track the migration of insecticides and fungicides into the inner region of foods. The results revealed that both the octanol-water partition coefficient of pesticides and water content of garden stuffs could influence the discrepancy in the migration speed of pesticides into food kernels. Taken together, this nanopaper imprinting MSI is poised to be a powerful tool because of its simplicity, rapidity, and easy operation, offering the potential to facilitate further applications in food analysis. Moreover, new perspectives are given to provide guidelines for the rational design of novel pesticide candidates, reducing the risk of food safety issues caused by pesticide residue. Full article
(This article belongs to the Special Issue Advances in Food Nanotechnology)
Show Figures

Figure 1

Article
Magneto-Plasmonic Nanoparticle Grid Biosensor with Enhanced Raman Scattering and Electrochemical Transduction for the Development of Nanocarriers for Targeted Delivery of Protected Anticancer Drugs
Nanomaterials 2021, 11(5), 1326; https://0-doi-org.brum.beds.ac.uk/10.3390/nano11051326 - 18 May 2021
Viewed by 558
Abstract
Safe administration of highly cytotoxic chemotherapeutic drugs is a challenging problem in cancer treatment due to the adverse side effects and collateral damage to non-tumorigenic cells. To mitigate these problems, promising new approaches, based on the paradigm of controlled targeted drug delivery (TDD), [...] Read more.
Safe administration of highly cytotoxic chemotherapeutic drugs is a challenging problem in cancer treatment due to the adverse side effects and collateral damage to non-tumorigenic cells. To mitigate these problems, promising new approaches, based on the paradigm of controlled targeted drug delivery (TDD), and utilizing drug nanocarriers with biorecognition ability to selectively target neoplastic cells, are being considered in cancer therapy. Herein, we report on the design and testing of a nanoparticle-grid based biosensing platform to aid in the development of new targeted drug nanocarriers. The proposed sensor grid consists of superparamagnetic gold-coated core–shell Fe2[email protected] nanoparticles, further functionalized with folic acid targeting ligand, model thiolated chemotherapeutic drug doxorubicin (DOX), and a biocompatibility agent, 3,6-dioxa-octanethiol (DOOT). The employed dual transduction method based on electrochemical and enhanced Raman scattering detection has enabled efficient monitoring of the drug loading onto the nanocarriers, attaching to the sensor surface, as well as the drug release under simulated intracellular conditions. The grid’s nanoparticles serve here as the model nanocarriers for new TDD systems under design and optimization. The superparamagnetic properties of the Fe2[email protected] NPs aid in nanoparticles’ handling and constructing a dense sensor grid with high plasmonic enhancement of the Raman signals due to the minimal interparticle distance. Full article
(This article belongs to the Special Issue Gold Nanoparticle-Based Biosensors)
Show Figures

Figure 1

Previous Issue
Next Issue
Back to TopTop