Bio-Based Polymers for Biomedical Applications

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Polymer Applications".

Deadline for manuscript submissions: closed (15 July 2023) | Viewed by 36530

Special Issue Editors

Pharmaceutical Technology Unit, Faculty of Pharmacy, AIMST University, Bedong 08100, Kedah, Malaysia
Interests: targeted drug delivery; mucoadhesion; nanotechnology; polymer blended pH-sensitive micro/nano-carrier; oral controlled drug delivery; polymer-based hydrogels; electrospray/electrospinning.

Special Issue Information

Dear Colleagues,

This Special Issue on “Bio-based polymers for biomedical applications” is devoted to the dissemination of high-quality original research articles or comprehensive reviews on cutting-edge developments in this interdisciplinary field with a focus on biomedical applications, i.e., drug delivery, tissue engineering, bioadhesion, etc. The ongoing advancement of tissue engineering and regenerative medicine requires new multifunctional and adaptive biopolymeric materials, which have to be appropriate for various medical applications.

In recent years, bio-based polymers, have been used and extensively studied in various applications, especially biomedical applications, because they are biocompatible, biodegradable, non-toxic, and environmentally friendly materials. The incorporation of a biologically active compound into the polymeric matrix can prevent degradation, control release, improve absorption, enhance therapeutic effect and potentially decrease the frequency of administration. In the design of suitable bio-based polymeric drug-delivery systems, the following key aspects must be considered: these materials should not produce an inflammatory reaction, should have suitable mechanical properties for their intended use, their degradation time should be in accordance with their function, and they should exhibit an appropriate permeability for the designed application. The biomedical polymers exhibit a far-reaching variability in their physical and chemical characteristics, allowing for the adjustment of their biocompatibility, bioactivity, stimuli responsiveness, biodegradability, etc.

Dr. Mireia Mallandrich
Dr. Abul Kalam Azad
Guest Editors

Manuscript Submission Information

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Keywords

  • bio-based and biodegradable polymeric composites 
  • polysaccharides 
  • site-specific-drug delivery matrix 
  • ph-sensitive polymeric composites 
  • polymers blended oral control drug-delivery systems 
  • polymers blended topical and transdermal formulations 
  • biopolymer synthesized carriers for skin drug delivery 
  • polymers-based bioactive compounds encapsulation 
  • polymers blended films and hydrogels for biomedical applications 
  • bio-based polymer characterization

Published Papers (10 papers)

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Research

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14 pages, 35146 KiB  
Article
Optimization Preparation and Evaluation of Chitosan Grafted Norfloxacin as a Hemostatic Sponge
by Yu Cheng, Qian Yang, Jiyuan Wang, Zhang Hu, Chengpeng Li, Saiyi Zhong and Na Huang
Polymers 2023, 15(3), 672; https://0-doi-org.brum.beds.ac.uk/10.3390/polym15030672 - 28 Jan 2023
Viewed by 1344
Abstract
Considering the great harm to the human body caused by severe and massive bleeding, in this study, chitosan-grafted norfloxacin (CTS-NF) composites were prepared with chitosan (CTS) and norfloxacin (NF) as raw materials by a 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide-mediated coupling method to solve the limitations of [...] Read more.
Considering the great harm to the human body caused by severe and massive bleeding, in this study, chitosan-grafted norfloxacin (CTS-NF) composites were prepared with chitosan (CTS) and norfloxacin (NF) as raw materials by a 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide-mediated coupling method to solve the limitations of slow hemostatic and poor anti-infective effects of current dressings on the market. The effects of the mass ratio of CTS to NF (MCTS/MNF), reaction temperature T and reaction time t on the grafting rate (η%) of the products were investigated through single factor tests. The preparation process was optimized with the η% as an evaluation index by means of the Box–Behnken test design and response surface analysis. The antimicrobial activity was evaluated by inhibition zone assay, and the hemostatic activity of the prepared composites was evaluated in vitro and in vivo. The results suggested that the optimum preparation conditions were the mass ratio of CTS to NF (MCTS/MNF) 5:3, reaction temperature 65 °C, and reaction time 4 h. Under this condition, the η% of CTS-NF was 45.5%. The CTS-NF composites displayed significant antimicrobial activities. Moreover, in vitro hemostasis results revealed that the CTS-NF composite had a lower blood clotting index and absorbed red blood cells to promote aggregation. In vivo ear and live hemostasis, the CTS-NF groups showed short hemostatic time (49.75 ± 3.32 s and 50.00 ± 7.21 s) and more blood loss (0.07 ± 0.010 g and 0.075 ± 0.013 g). The results showed that CTS-NF reduced the bleeding time and volume, exhibiting a significant coagulation effect. Therefore, the CTS-NF sponge is expected to be a new, effective hemostatic and antibacterial material in the future. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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10 pages, 2040 KiB  
Article
The Chemotherapeutic Efficacy of Hyaluronic Acid Coated Polymeric Nanoparticles against Breast Cancer Metastasis in Female NCr-Nu/Nu Nude Mice
by Hassan A. Almoustafa, Mohammed Abdullah Alshawsh, Fouad Saleih R. Al-Suede, Salah Abdulrazak Alshehade, Amin Malik Shah Abdul Majid and Zamri Chik
Polymers 2023, 15(2), 284; https://0-doi-org.brum.beds.ac.uk/10.3390/polym15020284 - 05 Jan 2023
Cited by 10 | Viewed by 2213
Abstract
Polyethylene glycol (PEG) coated Poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs) for cancer treatment are biocompatible, nonimmunogenic and accumulate in tumour sites due to the enhanced permeability and retention (EPR). Doxorubicin (DOX) is a potent but cardiotoxic anticancer agent. Hyaluronic acid (HA) occurs naturally [...] Read more.
Polyethylene glycol (PEG) coated Poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs) for cancer treatment are biocompatible, nonimmunogenic and accumulate in tumour sites due to the enhanced permeability and retention (EPR). Doxorubicin (DOX) is a potent but cardiotoxic anticancer agent. Hyaluronic acid (HA) occurs naturally in the extra-cellar matrix and binds to CD44 receptors which are overexpressed in cancer metastasis, proven to be characteristic of cancer stem cells and responsible for multidrug resistance. In this study, an athymic mice model of breast cancer metastasis was developed using red fluorescent protein (RFP)-labelled triple negative cancer cells. The animals were divided into four treatment groups (Control, HA-PEG-PLGA nanoparticles, PEG-PLGA nanoparticles, and Free DOX). The tumour size growth was assessed until day 25 when animals were sacrificed. Mice treated with HA-PEG-PLGA NPs inhibited tumour growth. The tumour growth at day 25 (118% ± 13.0) was significantly (p < 0.05) less than PEG-PLGA NPs (376% ± 590 and control (826% ± 970). Fluorescent microscopy revealed that HA-PEG-PLGA NPs had significantly (p < 0.05) less metastasis in liver, spleen, colon, and lungs as compared to control and to Free DOX groups. The efficacy of HA-PEG-PLGA NPs was proven in vivo. Further pharmacokinetic and toxicity studies are required for this formulation to be ready for clinical research. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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19 pages, 10061 KiB  
Article
Histological Evaluation of Cassava Starch/Chicken Gelatin Membranes
by Carlos Humberto Valencia-Llano, Jorge Iván Castro, Marcela Saavedra, Paula A. Zapata, Diana Paola Navia-Porras, Edwin Flórez-López, Carolina Caicedo, Heidy Lorena Calambas and Carlos David Grande-Tovar
Polymers 2022, 14(18), 3849; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14183849 - 14 Sep 2022
Viewed by 1602
Abstract
The use of biopolymers for tissue engineering has recently gained attention due to the need for safer and highly compatible materials. Starch is one of the most used biopolymers for membrane preparation. However, incorporating other polymers into starch membranes introduces improvements, such as [...] Read more.
The use of biopolymers for tissue engineering has recently gained attention due to the need for safer and highly compatible materials. Starch is one of the most used biopolymers for membrane preparation. However, incorporating other polymers into starch membranes introduces improvements, such as better thermal and mechanical resistance and increased water affinity, as we reported in our previous work. There are few reports in the literature on the biocompatibility of starch/chicken gelatin composites. We assessed the in vivo biocompatibility of the five composites (T1–T5) cassava starch/gelatin membranes with subdermal implantations in biomodels at 30, 60, and 90 days. The FT-IR spectroscopy analysis demonstrated the main functional groups for starch and chicken gelatin. At the same time, the thermal study exhibited an increase in thermal resistance for T3 and T4, with a remaining mass (~15 wt.%) at 800 °C. The microstructure analysis for the T2–T4 demonstrated evident roughness changes with porosity presence due to starch and gelatin mixture. The decrease in the starch content in the composites also decreased the gelatinization heats for T3 and T4 (195.67, 196.40 J/g, respectively). Finally, the implantation results demonstrated that the formulations exhibited differences in the degradation and resorption capacities according to the starch content, which is easily degraded by amylases. However, the histological results showed that the samples demonstrated almost complete reabsorption without a severe immune response, indicating a high in vivo biocompatibility. These results show that the cassava starch/chicken gelatin composites are promising membrane materials for tissue engineering applications. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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13 pages, 2976 KiB  
Article
Alginate-Based Hydrogel as Delivery System for Therapeutic Bacterial RNase
by Liliya R. Bogdanova, Pavel V. Zelenikhin, Anastasiya O. Makarova, Olga S. Zueva, Vadim V. Salnikov, Yuriy F. Zuev and Olga N. Ilinskaya
Polymers 2022, 14(12), 2461; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14122461 - 16 Jun 2022
Cited by 12 | Viewed by 2199
Abstract
To deliver therapeutic proteins into a living body, it is important to maintain their target activity in the gastrointestinal tract after oral administration. Secreted ribonuclease from Bacillus pumilus (binase) has antitumor and antiviral activity, which makes it a promising therapeutic agent. This globular [...] Read more.
To deliver therapeutic proteins into a living body, it is important to maintain their target activity in the gastrointestinal tract after oral administration. Secreted ribonuclease from Bacillus pumilus (binase) has antitumor and antiviral activity, which makes it a promising therapeutic agent. This globular protein of small molecular weight (12.2 kDa) is considered as a potential agent that induces apoptosis of tumor cells expressing certain oncogenes, including colorectal and duodenum cancer. The most important problem of its usage is the preservation of its structure and target activity, which could be lost during oral administration. Here, we developed alginate microspheres reinforced with divalent cations and analyzed the enzyme release from them. Using methods of scanning electron microscopy, measurements of fluorescence, enzyme catalytic activity, and determination of viability of the duodenum adenocarcinoma tumor cell line, we characterized obtained microspheres and chose calcium as a biogenic ion-strengthening microsphere structure. Among such modified additivities as beta-casein, gelatin, and carbon nanotubes introduced into microspheres, only gelatin showed a pronounced increase in their stability and provided data on the prolonged action of enzyme release from microspheres into tumor cell culture medium during 48 h in an amount of about 70% of the loaded quantity. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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14 pages, 2893 KiB  
Article
Characterization of Microwave-Controlled Polyacrylamide Graft Copolymer of Tamarind Seed Polysaccharide
by Sheetal Jha, Rishabha Malviya, Shivkanya Fuloria, Sonali Sundram, Vetriselvan Subramaniyan, Mahendran Sekar, Pradeep Kumar Sharma, Srikumar Chakravarthi, Yuan Seng Wu, Neelesh Mishra, Dhanalekshmi Unnikrishnan Meenakshi, Vijay Bhalla, Sinouvassane Djearamane and Neeraj Kumar Fuloria
Polymers 2022, 14(5), 1037; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14051037 - 04 Mar 2022
Cited by 8 | Viewed by 2774
Abstract
The main objective of the study was to prepare tamarind seed polysaccharide grafted copolymers of polyacrylamide (TSP-g-Am) using a 32 factorial design. Tamarind seed polysaccharide (TSP) was extracted, and grafted copolymer of TSP was prepared using polyacrylamide as copolymer and ceric ammonium [...] Read more.
The main objective of the study was to prepare tamarind seed polysaccharide grafted copolymers of polyacrylamide (TSP-g-Am) using a 32 factorial design. Tamarind seed polysaccharide (TSP) was extracted, and grafted copolymer of TSP was prepared using polyacrylamide as copolymer and ceric ammonium nitrate as initiator. Various batches (F1-F9) of TSP-g-Am were prepared, among which F1 showed highest grafting efficiency; hence, the prepared TSP-g-Am (F1) was evaluated for grafting efficiency, conversion, effect of initiator and further characterized using SEM analysis, contact angle determination, DSC analysis, swelling index, swelling and deswelling, and chemical resistance. The contact angle of TSP was found to be 81 ± 2, and that of TSP-g-Am (F1) was found to be 74 ± 2, which indicates that the wetting ability of the grafted copolymer was less than that of the native polymer. The results of thermal analysis indicated that TSP-g-Am had a more stable molecular structure than TSP. The morphology of the grafted polymer was observed from SEM images, and it was observed that the particles was asymmetrical. Antimicrobial activity was also found in the grafted copolymer. The present study concludes that the TSP-g-Am showed an excellent performance in thermal stability and swelling capacity compared with TSP. The detailed structural characteristics, as well as the excellent thermal stability and swelling capacities, will make it beneficial to use the synthesised copolymer as a precursor for the production of large-scale eco-friendly advanced materials with a wide range of applications, acting as a stabiliser, thickener, binder, release retardant, modifier, suspending agent, viscosity enhancer, emulsifying agent, or carrier for novel drug delivery systems in oral, buccal, colon, and ocular systems, and in nanofabrication and wound dressing, and it is also becoming an important part of food, cosmetics, confectionery, and bakery. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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29 pages, 72040 KiB  
Article
Thiolated Chitosan Microneedle Patch of Levosulpiride from Fabrication, Characterization to Bioavailability Enhancement Approach
by Rukhshanda Habib, Abul Kalam Azad, Muhammad Akhlaq, Fakhria A. Al-Joufi, Gul Shahnaz, Hanan R. H. Mohamed, Muhammad Naeem, Abdulraheem S. A. Almalki, Junaid Asghar, Aamir Jalil and Mohamed M. Abdel-Daim
Polymers 2022, 14(3), 415; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14030415 - 20 Jan 2022
Cited by 11 | Viewed by 4006
Abstract
In this study, a first attempt has been made to deliver levosulpiride transdermally through a thiolated chitosan microneedle patch (TC-MNP). Levosulpiride is slowly and weakly absorbed from the gastrointestinal tract with an oral bioavailability of less than 25% and short half-life of about [...] Read more.
In this study, a first attempt has been made to deliver levosulpiride transdermally through a thiolated chitosan microneedle patch (TC-MNP). Levosulpiride is slowly and weakly absorbed from the gastrointestinal tract with an oral bioavailability of less than 25% and short half-life of about 6 h. In order to enhance its bioavailability, levosulpiride-loaded thiolated chitosan microneedle patches (LS-TC-MNPs) were fabricated. Firstly, thiolated chitosan was synthesized and characterized by nuclear magnetic resonance (1HNMR) spectroscopy, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Thiolated chitosan has been used in different drug delivery systems; herein, thiolated chitosan has been used for the transdermal delivery of LS. LS-TC-MNPs were fabricated from different concentrations of thiolated chitosan solution. Furthermore, the levosulpiride-loaded thiolated chitosan microneedle patch (LS-TC-MNP) was characterized by FTIR spectroscopic analysis, scanning electron microscopy (SEM) study, penetration ability, tensile strength, moisture content, patch thickness, and elongation test. LS-TC-MNP fabricated with 3% thiolated chitosan solution was found to have the best tensile strength, moisture content, patch thickness, elongation, drug-loading efficiency, and drug content. Thiolated chitosan is biodegradable, nontoxic and has good absorption and swelling in the skin. LS-TC-MNP-3 consists of 100 needles in 10 rows each with 10 needles. The length of each microneedle was 575 μm; they were pyramidal in shape, with sharp pointed ends and a base diameter of 200 µm. The microneedle patch (LS-TC-MNP-3) resulted in-vitro drug release of 65% up to 48 h, ex vivo permeation of 63.6%, with good skin biocompatibility and enhanced in-vivo pharmacokinetics (AUC = 986 µg/mL·h, Cmax = 24.5 µg/mL) as compared to oral LS dispersion (AUC = 3.2 µg/mL·h, Cmax = 0.5 µg/mL). Based on the above results, LS-TC-MNP-3 seems to be a promising strategy for enhancing the bioavailability of levosulpiride. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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17 pages, 2755 KiB  
Article
Formulation Development, Characterization and Antifungal Evaluation of Chitosan NPs for Topical Delivery of Voriconazole In Vitro and Ex Vivo
by Muhammad Khurshid Alam Shah, Abul Kalam Azad, Asif Nawaz, Shafi Ullah, Muhammad Shahid Latif, Habibur Rahman, Khalaf F. Alsharif, Khalid J. Alzahrani, Attalla F. El-Kott, Ashraf Albrakati and Mohamed M. Abdel-Daim
Polymers 2022, 14(1), 135; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14010135 - 30 Dec 2021
Cited by 21 | Viewed by 2885
Abstract
This study aims to develop chitosan-based voriconazole nanoparticles (NPs) using spray-drying technique. The effect of surfactants and polymers on the physicochemical properties, in vitro release, and permeation of NPs was investigated. The prepared NPs containing various surfactants and polymers (e.g., Tween 20 (T20), [...] Read more.
This study aims to develop chitosan-based voriconazole nanoparticles (NPs) using spray-drying technique. The effect of surfactants and polymers on the physicochemical properties, in vitro release, and permeation of NPs was investigated. The prepared NPs containing various surfactants and polymers (e.g., Tween 20 (T20), Tween 80 (T80), sodium lauryl sulfate (SLS), propylene glycol (PG), and Polyethylene glycol-4000 (PEG-4000)) were physiochemically evaluated for size, zeta potential, drug content, percent entrapment efficiency, in vitro release, and permeation across rats’ skin. A Franz diffusion cell was used for evaluating the in vitro release and permeation profile. The voriconazole-loaded NPs were investigated for antifungal activity against Candida albicans (C. albicans). The prepared NPs were in the nano range (i.e., 160–500 nm) and positively charged. Images taken by a scanning electron microscope showed that all prepared NPs were spherical and smooth. The drug content of NPs ranged from 75% to 90%. Nanoparticle formulations exhibited a good in vitro release profile and transport voriconazole across the rat’s skin in a slow control release manner. The NPs containing SLS, T80, and PG exhibited the best penetration and skin retention profile. In addition, the formulation exhibited a potential antifungal effect against C. albicans. It was concluded that the development of chitosan NPs has a great potential for the topical delivery of voriconazole against fungal infection. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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22 pages, 1207 KiB  
Article
Fabrication of Tizanidine Loaded Patches Using Flaxseed Oil and Coriander Oil as a Penetration Enhancer for Transdermal Delivery
by Muhammad Akhlaq, Abul Kalam Azad, Shivkanya Fuloria, Dhanalekshmi Unnikrishnan Meenakshi, Sajid Raza, Muhammad Safdar, Asif Nawaz, Vetriselvan Subramaniyan, Mahendran Sekar, Kathiresan V. Sathasivam, Yuan Seng Wu, Mireia Mallandrich Miret and Neeraj Kumar Fuloria
Polymers 2021, 13(23), 4217; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13234217 - 01 Dec 2021
Cited by 16 | Viewed by 2933
Abstract
Transdermal drug delivery is important to maintain plasma drug concentrations for therapeutic efficacy. The current study reports the design, formulation, and evaluation of tizanidine transdermal patches formulated using chitosan and thiolated chitosan, ethyl cellulose (EC), polyvinylpyrrolidone (PVP), and Eudragit RL100 in different ratios. [...] Read more.
Transdermal drug delivery is important to maintain plasma drug concentrations for therapeutic efficacy. The current study reports the design, formulation, and evaluation of tizanidine transdermal patches formulated using chitosan and thiolated chitosan, ethyl cellulose (EC), polyvinylpyrrolidone (PVP), and Eudragit RL100 in different ratios. The tizanidine patches were formulated using flaxseed oil and coriander oil in the concentrations of 1% v/w, 2% v/w, 3% v/w, 4% v/w, 5% v/w, and 10% v/w. The patches were subjected to characterization of physicochemical property (thickness, weight uniformity, drug content, efficiency, percentage moisture uptake/loss), in vitro drug release and drug permeation, skin irritation, in vivo application, pharmacokinetics analysis, and stability studies. The results indicate that the interaction of thiolated chitosan with the negative charges of the skin opens the tight junctions of the skin, whereas flaxseed and coriander oils change the conformational domain of the skin. The novelty of this study is in the use of flaxseed and coriander oils as skin permeation enhancers for the formulation of tizanidine transdermal patches. The formulations follow non-Fickian drug release kinetics. The FTZNE23, FTZNE36 and FTZNE54, with 5% v/w flaxseed oil loaded formulations, exhibited higher flux through rabbit skin compared with FTZNE30, FTZNE35, FTZNE42, and FTZNE47, formulations loaded with 10% v/w coriander oil. The study concludes that flaxseed oil is a better choice for formulating tizanidine patches, offering optimal plasma concentration and therapeutic efficacy, and recommends the use of flaxseed and coriander oil based patches as a novel transdermal delivery system for tizanidine and related classes of drugs. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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Review

Jump to: Research

63 pages, 11801 KiB  
Review
Liposomes or Extracellular Vesicles: A Comprehensive Comparison of Both Lipid Bilayer Vesicles for Pulmonary Drug Delivery
by Ali Al-Jipouri, Samah Hamed Almurisi, Khater Al-Japairai, Latifah Munirah Bakar and Abd Almonem Doolaanea
Polymers 2023, 15(2), 318; https://0-doi-org.brum.beds.ac.uk/10.3390/polym15020318 - 07 Jan 2023
Cited by 8 | Viewed by 5520
Abstract
The rapid and non-invasive pulmonary drug delivery (PDD) has attracted great attention compared to the other routes. However, nanoparticle platforms, like liposomes (LPs) and extracellular vesicles (EVs), require extensive reformulation to suit the requirements of PDD. LPs are artificial vesicles composed of lipid [...] Read more.
The rapid and non-invasive pulmonary drug delivery (PDD) has attracted great attention compared to the other routes. However, nanoparticle platforms, like liposomes (LPs) and extracellular vesicles (EVs), require extensive reformulation to suit the requirements of PDD. LPs are artificial vesicles composed of lipid bilayers capable of encapsulating hydrophilic and hydrophobic substances, whereas EVs are natural vesicles secreted by cells. Additionally, novel LPs-EVs hybrid vesicles may confer the best of both. The preparation methods of EVs are distinguished from LPs since they rely mainly on extraction and purification, whereas the LPs are synthesized from their basic ingredients. Similarly, drug loading methods into/onto EVs are distinguished whereby they are cell- or non-cell-based, whereas LPs are loaded via passive or active approaches. This review discusses the progress in LPs and EVs as well as hybrid vesicles with a special focus on PDD. It also provides a perspective comparison between LPs and EVs from various aspects (composition, preparation/extraction, drug loading, and large-scale manufacturing) as well as the future prospects for inhaled therapeutics. In addition, it discusses the challenges that may be encountered in scaling up the production and presents our view regarding the clinical translation of the laboratory findings into commercial products. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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27 pages, 52615 KiB  
Review
Atomic Force Microscopy (AFM) on Biopolymers and Hydrogels for Biotechnological Applications—Possibilities and Limits
by Jnanada Joshi, Sarah Vanessa Homburg and Andrea Ehrmann
Polymers 2022, 14(6), 1267; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14061267 - 21 Mar 2022
Cited by 28 | Viewed by 8366
Abstract
Atomic force microscopy (AFM) is one of the microscopic techniques with the highest lateral resolution. It can usually be applied in air or even in liquids, enabling the investigation of a broader range of samples than scanning electron microscopy (SEM), which is mostly [...] Read more.
Atomic force microscopy (AFM) is one of the microscopic techniques with the highest lateral resolution. It can usually be applied in air or even in liquids, enabling the investigation of a broader range of samples than scanning electron microscopy (SEM), which is mostly performed in vacuum. Since it works by following the sample surface based on the force between the scanning tip and the sample, interactions have to be taken into account, making the AFM of irregular samples complicated, but on the other hand it allows measurements of more physical parameters than pure topography. This is especially important for biopolymers and hydrogels used in tissue engineering and other biotechnological applications, where elastic properties, surface charges and other parameters influence mammalian cell adhesion and growth as well as many other effects. This review gives an overview of AFM modes relevant for the investigations of biopolymers and hydrogels and shows several examples of recent applications, focusing on the polysaccharides chitosan, alginate, carrageenan and different hydrogels, but depicting also a broader spectrum of materials on which different AFM measurements are reported in the literature. Full article
(This article belongs to the Special Issue Bio-Based Polymers for Biomedical Applications)
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