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Micromachines
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Analysis, Design and Fabrication of Micromixers, Volume II
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Analysis, Design and Fabrication of Micromixers, Volume II

A special issue of Micromachines (ISSN 2072-666X).

Deadline for manuscript submissions: closed (15 November 2022) | Viewed by 31699
Please contact the guest editor or the journal editor ([email protected]) for any queries.

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editor

Prof. Dr. Kwang-Yong Kim

E-Mail Website
Guest Editor
Department of Mechanical Engineering, Inha University, Incheon 22212, Republic of Korea
Interests: micromixer; micro heat sink; fluid machinery; optimization; heat transfer
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Micromixers are an important component in micrototal analysis systems and lab-on-a-chip platforms which are widely used for sample preparation and analysis, drug delivery, and biological and chemical synthesis. The successful operation of microfluidic devices requires fast and adequate mixing, but mixing is a challenging task due to the laminar feature of the flow at the microscale. Mixing in laminar flows relies on diffusion and requires a longer channel to achieve complete mixing due to the slow process compared to that in turbulent flows. Hence, it is crucial to overcome this challenge to improve the mixing performance. Based on their mixing mechanism, micromixers are classified into two types: active and passive. Passive micromixers are easy to fabricate and generally use geometry modification to cause chaotic advection or lamination to promote the mixing of fluid samples, unlike active micromixers, which use moving parts or some external agitation/energy for the mixing. The current Special Issue covers new mechanisms, numerical and/or experimental mixing analysis, design, and fabrication of various micromixers. 

Prof. Dr. Kwang-Yong Kim
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Micromachines is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • micromixer
  • mixing
  • microfluidic device
  • analysis
  • design
  • fabrication

Related Special Issue

Published Papers (14 papers)

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Editorial

Jump to: Research, Review

3 pages, 185 KiB  
Editorial
Editorial for the Special Issue on Analysis, Design and Fabrication of Micromixers II
by Kwang-Yong Kim
Micromachines 2022, 13(12), 2176; https://0-doi-org.brum.beds.ac.uk/10.3390/mi13122176 - 08 Dec 2022
Cited by 1 | Viewed by 730
Abstract
Micromixers are important components of lab-on-a-chip systems, and also have many biological and chemical applications [...] Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)

Research

Jump to: Editorial, Review

17 pages, 7824 KiB  
Article
Mixing Performance of the Modified Tesla Micromixer with Tip Clearance
by Makhsuda Juraeva and Dong-Jin Kang
Micromachines 2022, 13(9), 1375; https://0-doi-org.brum.beds.ac.uk/10.3390/mi13091375 - 23 Aug 2022
Cited by 6 | Viewed by 1701
Abstract
A passive micromixer based on the modified Tesla mixing unit was designed by embedding tip clearance above the wedge-shape divider, and its mixing performance was simulated over a wider range of the Reynolds numbers from 0.1 to 80. The mixing performance was evaluated [...] Read more.
A passive micromixer based on the modified Tesla mixing unit was designed by embedding tip clearance above the wedge-shape divider, and its mixing performance was simulated over a wider range of the Reynolds numbers from 0.1 to 80. The mixing performance was evaluated in terms of the degree of mixing (DOM) at the outlet and the required pressure load between inlet and outlet. The height of tip clearance was varied from 40 μm to 80 μm, corresponding to 25% to 33% of the micromixer depth. The numerical results show that the mixing enhancement by the tip clearance is noticeable over a wide range of the Reynolds numbers Re < 50. The height of tip clearance is optimized in terms of the DOM, and the optimum value is roughly h = 60 μm. It corresponds to 33% of the present micromixer depth. The mixing enhancement in the molecular diffusion regime of mixing, Re ≤ 1, is obtained by drag and connection of the interface in the two sub-streams of each Tesla mixing unit. It appears as a wider interface in the tip clearance zone. In the intermediate range of the Reynolds number, 1 < Re ≤ 50, the mixing enhancement is attributed to the interaction of the flow through the tip clearance and the secondary flow in the vortex zone of each Tesla mixing unit. When the Reynolds number is larger than about 50, vortices are formed at various locations and drive the mixing in the modified Tesla micromixer. For the Reynolds number of Re = 80, a pair of vortices is formed around the inlet and outlet of each Tesla mixing unit, and it plays a role as a governing mechanism in the convection-dominant regime of mixing. This vortex pattern is little affected as long as the tip clearance remains smaller than about h = 70 μm. The DOM at the outlet is little enhanced by the presence of tip clearance for the Reynolds numbers Re ≥ 50. The tip clearance contributes to reducing the required pressure load for the same value of the DOM. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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17 pages, 3918 KiB  
Article
Evaluation of Hydrodynamic and Thermal Behaviour of Non-Newtonian-Nanofluid Mixing in a Chaotic Micromixer
by Naas Toufik Tayeb, Shakhawat Hossain, Abid Hossain Khan, Telha Mostefa and Kwang-Yong Kim
Micromachines 2022, 13(6), 933; https://0-doi-org.brum.beds.ac.uk/10.3390/mi13060933 - 11 Jun 2022
Cited by 4 | Viewed by 1653
Abstract
Three-dimensional numerical investigations of a novel passive micromixer were carried out to analyze the hydrodynamic and thermal behaviors of Nano-Non-Newtonian fluids. Mass and heat transfer characteristics of two heated fluids have been investigated to understand the quantitative and qualitative fluid faction distributions with [...] Read more.
Three-dimensional numerical investigations of a novel passive micromixer were carried out to analyze the hydrodynamic and thermal behaviors of Nano-Non-Newtonian fluids. Mass and heat transfer characteristics of two heated fluids have been investigated to understand the quantitative and qualitative fluid faction distributions with temperature homogenization. The effect of fluid behavior and different Al2O3 nanoparticles concentrations on the pressure drop and thermal mixing performances were studied for different Reynolds number (from 0.1 to 25). The performance improvement simulation was conducted in intervals of various Nanoparticles concentrations (φ = 0 to 5%) with Power-law index (n) using CFD. The proposed micromixer displayed a mixing energy cost of 50–60 comparable to that achieved for a recent micromixer (2021y) in terms of fluid homogenization. The analysis exhibited that for high nanofluid concentrations, having a strong chaotic flow enhances significantly the hydrodynamic and thermal performances for all Reynolds numbers. The visualization of vortex core region of mass fraction and path lines presents that the proposed design exhibits a rapid thermal mixing rate that tends to 0.99%, and a mass fraction mixing rate of more than 0.93% with very low pressure losses, thus the proposed micromixer can be utilized to enhance homogenization in different Nano-Non-Newtonian mechanism with minimum energy. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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20 pages, 9392 KiB  
Article
A Numerical Investigation of the Mixing Performance in a Y-Junction Microchannel Induced by Acoustic Streaming
by Sintayehu Assefa Endaylalu and Wei-Hsin Tien
Micromachines 2022, 13(2), 338; https://0-doi-org.brum.beds.ac.uk/10.3390/mi13020338 - 21 Feb 2022
Cited by 7 | Viewed by 2136
Abstract
In this study, the mixing performance in a Y-junction microchannel with acoustic streaming was investigated through numerical simulation. The acoustic streaming is created by inducing triangular structures at the junction and sidewalls regions. The numerical model utilizes Navier–Stokes equations in conjunction with the [...] Read more.
In this study, the mixing performance in a Y-junction microchannel with acoustic streaming was investigated through numerical simulation. The acoustic streaming is created by inducing triangular structures at the junction and sidewalls regions. The numerical model utilizes Navier–Stokes equations in conjunction with the convection–diffusion equations. The parameters investigated were inlet velocities ranging from 4.46 to 55.6 µm/s, triangular structure’s vertex angles ranging from 22° to 90° oscillation amplitude ranging from 3 to 6 µm, and an oscillation frequency set to 13 kHz. The results show that at the junction region, a pair of counter-rotating streaming vortices were formed, and unsymmetrical or one-sided vortices were formed when additional triangles were added along the sidewalls. These streaming flows significantly increase the vorticity compared with the case without the acoustic stream. Mixing performances were found to have improved with the generation of the acoustic stream. The mixing performance was evaluated at various inlet velocities, the vertex angles of the triangular structure, and oscillation amplitudes. The numerical results show that adding the triangular structure at the junction region considerably improved the mixing efficiency due to the generation of acoustic streaming, and further improvements can be achieved at lower inlet velocity, sharper vertex angle, and higher oscillation amplitude. Integrating with more triangular structures at the sidewall regions also improves the mixing performance within the laminar flow regime in the Y-microchannel. At Y = 2.30 mm, oscillation amplitude of 6 µm, and flow inlet velocity of 55.6 µm/s, with all three triangles integrated and the triangles’ vertex angles fixed to 30°, the mixing index can achieve the best results of 0.9981, which is better than 0.8355 in the case of using only the triangle at the junction, and 0.6642 in the case without acoustic streaming. This is equal to an improvement of 50.27% in the case of using both the junction and the two sidewall triangles, and 25.79% in the case of simply using a junction triangle. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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17 pages, 11456 KiB  
Article
Generation of Concentration Gradients by a Outer-Circumference-Driven On-Chip Mixer
by Fumiya Koike and Toshio Takayama
Micromachines 2022, 13(1), 68; https://0-doi-org.brum.beds.ac.uk/10.3390/mi13010068 - 31 Dec 2021
Cited by 1 | Viewed by 1693
Abstract
The concentration control of reagents is an important factor in microfluidic devices for cell cultivation and chemical mixing, but it is difficult to realize owing to the characteristics of microfluidic devices. We developed a microfluidic device that can generate concentration gradients among multiple [...] Read more.
The concentration control of reagents is an important factor in microfluidic devices for cell cultivation and chemical mixing, but it is difficult to realize owing to the characteristics of microfluidic devices. We developed a microfluidic device that can generate concentration gradients among multiple main chambers. Multiple main chambers are connected in parallel to the body channel via the neck channel. The main chamber is subjected to a volume change through a driving chamber that surrounds the main chamber, and agitation is performed on the basis of the inequality of flow caused by expansion or contraction. The neck channel is connected tangentially to the main chamber. When the main chamber expands or contracts, the flow in the main chamber is unequal, and a net vortex is generated. The liquid moving back and forth in the neck channel gradually absorbs the liquid in the body channel into the main chamber. As the concentration in the main chamber changes depending on the pressure applied to the driving chamber, we generated a concentration gradient by arranging chambers along the pressure gradient. This allowed for us to create an environment with different concentrations on a single microchip, which is expected to improve observation efficiency and save space. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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14 pages, 4778 KiB  
Article
Rapid AC Electrokinetic Micromixer with Electrically Conductive Sidewalls
by Fang Yang, Wei Zhao, Cuifang Kuang and Guiren Wang
Micromachines 2022, 13(1), 34; https://0-doi-org.brum.beds.ac.uk/10.3390/mi13010034 - 27 Dec 2021
Cited by 5 | Viewed by 2192
Abstract
We report a quasi T-channel electrokinetics-based micromixer with electrically conductive sidewalls, where the electric field is in the transverse direction of the flow and parallel to the conductivity gradient at the interface between two fluids to be mixed. Mixing results are first compared [...] Read more.
We report a quasi T-channel electrokinetics-based micromixer with electrically conductive sidewalls, where the electric field is in the transverse direction of the flow and parallel to the conductivity gradient at the interface between two fluids to be mixed. Mixing results are first compared with another widely studied micromixer configuration, where electrodes are located at the inlet and outlet of the channel with electric field parallel to bulk flow direction but orthogonal to the conductivity gradient at the interface between the two fluids to be mixed. Faster mixing is achieved in the micromixer with conductive sidewalls. Effects of Re numbers, applied AC voltage and frequency, and conductivity ratio of the two fluids to be mixed on mixing results were investigated. The results reveal that the mixing length becomes shorter with low Re number and mixing with increased voltage and decreased frequency. Higher conductivity ratio leads to stronger mixing result. It was also found that, under low conductivity ratio, compared with the case where electrodes are located at the end of the channel, the conductive sidewalls can generate fast mixing at much lower voltage, higher frequency, and lower conductivity ratio. The study of this micromixer could broaden our understanding of electrokinetic phenomena and provide new tools for sample preparation in applications such as organ-on-a-chip where fast mixing is required. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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17 pages, 5004 KiB  
Article
Mixing Performance of a Passive Micro-Mixer with Mixing Units Stacked in Cross Flow Direction
by Makhsuda Juraeva and Dong-Jin Kang
Micromachines 2021, 12(12), 1530; https://0-doi-org.brum.beds.ac.uk/10.3390/mi12121530 - 09 Dec 2021
Cited by 11 | Viewed by 2386
Abstract
A new passive micro-mixer with mixing units stacked in the cross flow direction was proposed, and its performance was evaluated numerically. The present micro-mixer consisted of eight mixing units. Each mixing unit had four baffles, and they were arranged alternatively in the cross [...] Read more.
A new passive micro-mixer with mixing units stacked in the cross flow direction was proposed, and its performance was evaluated numerically. The present micro-mixer consisted of eight mixing units. Each mixing unit had four baffles, and they were arranged alternatively in the cross flow and transverse direction. The mixing units were stacked in four different ways: one step, two step, four step, and eight step stacking. A numerical study was carried out for the Reynolds numbers from 0.5 to 50. The corresponding volume flow rate ranged from 6.33 μL/min to 633 μL/min. The mixing performance was analyzed in terms of the degree of mixing (DOM) and relative mixing energy cost (MEC). The numerical results showed a noticeable enhancement of the mixing performance compared with other micromixers. The mixing enhancement was achieved by two flow characteristics: baffle wall impingement by a stream of high concentration and swirl motion within the mixing unit. The baffle wall impingement by a stream of high concentration was observed throughout all Reynolds numbers. The swirl motion inside the mixing unit was observed in the cross flow direction, and became significant as the Reynolds number increased to larger than about five. The eight step stacking showed the best performance for Reynolds numbers larger than about two, while the two step stacking was better for Reynolds numbers less than about two. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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12 pages, 6434 KiB  
Article
Mixing Enhancement of Non-Newtonian Shear-Thinning Fluid for a Kenics Micromixer
by Abdelkader Mahammedi, Naas Toufik Tayeb, Kwang-Yong Kim and Shakhawat Hossain
Micromachines 2021, 12(12), 1494; https://0-doi-org.brum.beds.ac.uk/10.3390/mi12121494 - 30 Nov 2021
Cited by 3 | Viewed by 2265
Abstract
In this work, a numerical investigation was analyzed to exhibit the mixing behaviors of non-Newtonian shear-thinning fluids in Kenics micromixers. The numerical analysis was performed using the computational fluid dynamic (CFD) tool to solve 3D Navier-Stokes equations with the species transport equations. The [...] Read more.
In this work, a numerical investigation was analyzed to exhibit the mixing behaviors of non-Newtonian shear-thinning fluids in Kenics micromixers. The numerical analysis was performed using the computational fluid dynamic (CFD) tool to solve 3D Navier-Stokes equations with the species transport equations. The efficiency of mixing is estimated by the calculation of the mixing index for different cases of Reynolds number. The geometry of micro Kenics collected with a series of six helical elements twisted 180° and arranged alternately to achieve the higher level of chaotic mixing, inside a pipe with a Y-inlet. Under a wide range of Reynolds numbers between 0.1 to 500 and the carboxymethyl cellulose (CMC) solutions with power-law indices among 1 to 0.49, the micro-Kenics proves high mixing Performances at low and high Reynolds number. Moreover the pressure losses of the shear-thinning fluids for different Reynolds numbers was validated and represented. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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13 pages, 2167 KiB  
Article
Numerical and Experimental Study of Cross-Sectional Effects on the Mixing Performance of the Spiral Microfluidics
by Omid Rouhi, Sajad Razavi Bazaz, Hamid Niazmand, Fateme Mirakhorli, Sima Mas-hafi, Hoseyn A. Amiri, Morteza Miansari and Majid Ebrahimi Warkiani
Micromachines 2021, 12(12), 1470; https://0-doi-org.brum.beds.ac.uk/10.3390/mi12121470 - 29 Nov 2021
Cited by 10 | Viewed by 2514
Abstract
Mixing at the microscale is of great importance for various applications ranging from biological and chemical synthesis to drug delivery. Among the numerous types of micromixers that have been developed, planar passive spiral micromixers have gained considerable interest due to their ease of [...] Read more.
Mixing at the microscale is of great importance for various applications ranging from biological and chemical synthesis to drug delivery. Among the numerous types of micromixers that have been developed, planar passive spiral micromixers have gained considerable interest due to their ease of fabrication and integration into complex miniaturized systems. However, less attention has been paid to non-planar spiral micromixers with various cross-sections and the effects of these cross-sections on the total performance of the micromixer. Here, mixing performance in a spiral micromixer with different channel cross-sections is evaluated experimentally and numerically in the Re range of 0.001 to 50. The accuracy of the 3D-finite element model was first verified at different flow rates by tracking the mixing index across the loops, which were directly proportional to the spiral radius and were hence also proportional to the Dean flow. It is shown that higher flow rates induce stronger vortices compared to lower flow rates; thus, fewer loops are required for efficient mixing. The numerical study revealed that a large-angle outward trapezoidal cross-section provides the highest mixing performance, reaching efficiencies of up to 95%. Moreover, the velocity/vorticity along the channel length was analyzed and discussed to evaluate channel mixing performance. A relatively low pressure drop (<130 kPa) makes these passive spiral micromixers ideal candidates for various lab-on-chip applications. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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14 pages, 3524 KiB  
Article
Mixing Mechanism of Microfluidic Mixer with Staggered Virtual Electrode Based on Light-Actuated AC Electroosmosis
by Liuyong Shi, Hanghang Ding, Xiangtao Zhong, Binfeng Yin, Zhenyu Liu and Teng Zhou
Micromachines 2021, 12(7), 744; https://0-doi-org.brum.beds.ac.uk/10.3390/mi12070744 - 24 Jun 2021
Cited by 6 | Viewed by 2054
Abstract
In this paper, we present a novel microfluidic mixer with staggered virtual electrode based on light-actuated AC electroosmosis (LACE). We solve the coupled system of the flow field described by Navier–Stokes equations, the described electric field by a Laplace equation, and the concentration [...] Read more.
In this paper, we present a novel microfluidic mixer with staggered virtual electrode based on light-actuated AC electroosmosis (LACE). We solve the coupled system of the flow field described by Navier–Stokes equations, the described electric field by a Laplace equation, and the concentration field described by a convection–diffusion equation via a finite-element method (FEM). Moreover, we study the distribution of the flow, electric, and concentration fields in the microchannel, and reveal the generating mechanism of the rotating vortex on the cross-section of the microchannel and the mixing mechanism of the fluid sample. We also explore the influence of several key geometric parameters such as the length, width, and spacing of the virtual electrode, and the height of the microchannel on mixing performance; the relatively optimal mixer structure is thus obtained. The current micromixer provides a favorable fluid-mixing method based on an optical virtual electrode, and could promote the comprehensive integration of functions in modern microfluidic-analysis systems. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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14 pages, 2268 KiB  
Article
Characterization of Mixing Performance Induced by Double Curved Passive Mixing Structures in Microfluidic Channels
by Ingrid H. Oevreeide, Andreas Zoellner and Bjørn T. Stokke
Micromachines 2021, 12(5), 556; https://0-doi-org.brum.beds.ac.uk/10.3390/mi12050556 - 13 May 2021
Cited by 4 | Viewed by 1951
Abstract
Functionalized sensor surfaces combined with microfluidic channels are becoming increasingly important in realizing efficient biosensing devices applicable to small sample volumes. Relaxing the limitations imposed by laminar flow of the microfluidic channels by passive mixing structures to enhance analyte mass transfer to the [...] Read more.
Functionalized sensor surfaces combined with microfluidic channels are becoming increasingly important in realizing efficient biosensing devices applicable to small sample volumes. Relaxing the limitations imposed by laminar flow of the microfluidic channels by passive mixing structures to enhance analyte mass transfer to the sensing area will further improve the performance of these devices. In this paper, we characterize the flow performance in a group of microfluidic flow channels with novel double curved passive mixing structures (DCMS) fabricated in the ceiling. The experimental strategy includes confocal imaging to monitor the stationary flow patterns downstream from the inlet where a fluorophore is included in one of the inlets in a Y-channel microfluidic device. Analyses of the fluorescence pattern projected both along the channel and transverse to the flow direction monitored details in the developing homogenization. The mixing index (MI) as a function of the channel length was found to be well accounted for by a double-exponential equilibration process, where the different parameters of the DCMS were found to affect the extent and length of the initial mixing component. The range of MI for a 1 cm channel length for the DCMS was 0.75–0.98, which is a range of MI comparable to micromixers with herringbone structures. Overall, this indicates that the DCMS is a high performing passive micromixer, but the sensitivity to geometric parameter values calls for the selection of certain values for the most efficient mixing. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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23 pages, 6254 KiB  
Article
Steric and Slippage Effects on Mass Transport by Using an Oscillatory Electroosmotic Flow of Power-Law Fluids
by Ruben Baños, José Arcos, Oscar Bautista and Federico Méndez
Micromachines 2021, 12(5), 539; https://0-doi-org.brum.beds.ac.uk/10.3390/mi12050539 - 10 May 2021
Cited by 7 | Viewed by 1823
Abstract
In this paper, the combined effect of the fluid rheology, finite-sized ions, and slippage toward augmenting a non-reacting solute’s mass transport due to an oscillatory electroosmotic flow (OEOF) is determined. Bikerman’s model is used to include the finite-sized ions (steric effects) in the [...] Read more.
In this paper, the combined effect of the fluid rheology, finite-sized ions, and slippage toward augmenting a non-reacting solute’s mass transport due to an oscillatory electroosmotic flow (OEOF) is determined. Bikerman’s model is used to include the finite-sized ions (steric effects) in the original Poisson-Boltzmann (PB) equation. The volume fraction of ions quantifies the steric effects in the modified Poisson-Boltzmann (MPB) equation to predict the electrical potential and the ion concentration close to the charged microchannel walls. The hydrodynamics is affected by slippage, in which the slip length was used as an index for wall hydrophobicity. A conventional finite difference scheme was used to solve the momentum and species transport equations in the lubrication limit together with the MPB equation. The results suggest that the combined slippage and steric effects promote the best conditions to enhance the mass transport of species in about 90% compared with no steric effect with proper choices of the Debye length, Navier length, steric factor, Womersley number, and the tidal displacement. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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Review

Jump to: Editorial, Research

32 pages, 15916 KiB  
Review
Microfluidic Applications of Artificial Cilia: Recent Progress, Demonstration, and Future Perspectives
by Vignesh Sahadevan, Bivas Panigrahi and Chia-Yuan Chen
Micromachines 2022, 13(5), 735; https://0-doi-org.brum.beds.ac.uk/10.3390/mi13050735 - 03 May 2022
Cited by 15 | Viewed by 4658
Abstract
Artificial cilia-based microfluidics is a promising alternative in lab-on-a-chip applications which provides an efficient way to manipulate fluid flow in a microfluidic environment with high precision. Additionally, it can induce favorable local flows toward practical biomedical applications. The endowment of artificial cilia with [...] Read more.
Artificial cilia-based microfluidics is a promising alternative in lab-on-a-chip applications which provides an efficient way to manipulate fluid flow in a microfluidic environment with high precision. Additionally, it can induce favorable local flows toward practical biomedical applications. The endowment of artificial cilia with their anatomy and capabilities such as mixing, pumping, transporting, and sensing lead to advance next-generation applications including precision medicine, digital nanofluidics, and lab-on-chip systems. This review summarizes the importance and significance of the artificial cilia, delineates the recent progress in artificial cilia-based microfluidics toward microfluidic application, and provides future perspectives. The presented knowledge and insights are envisaged to pave the way for innovative advances for the research communities in miniaturization. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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19 pages, 11452 KiB  
Review
Recent Advances and Future Perspectives on Microfluidic Mix-and-Jet Sample Delivery Devices
by Majid Hejazian, Eugeniu Balaur and Brian Abbey
Micromachines 2021, 12(5), 531; https://0-doi-org.brum.beds.ac.uk/10.3390/mi12050531 - 07 May 2021
Cited by 10 | Viewed by 2676
Abstract
The integration of the Gas Dynamic Virtual Nozzle (GDVN) and microfluidic technologies has proven to be a promising sample delivery solution for biomolecular imaging studies and has the potential to be transformative for a range of applications in physics, biology, and chemistry. Here, [...] Read more.
The integration of the Gas Dynamic Virtual Nozzle (GDVN) and microfluidic technologies has proven to be a promising sample delivery solution for biomolecular imaging studies and has the potential to be transformative for a range of applications in physics, biology, and chemistry. Here, we review the recent advances in the emerging field of microfluidic mix-and-jet sample delivery devices for the study of biomolecular reaction dynamics. First, we introduce the key parameters and dimensionless numbers involved in their design and characterisation. Then we critically review the techniques used to fabricate these integrated devices and discuss their advantages and disadvantages. We then summarise the most common experimental methods used for the characterisation of both the mixing and jetting components. Finally, we discuss future perspectives on the emerging field of microfluidic mix-and-jet sample delivery devices. In summary, this review aims to introduce this exciting new topic to the wider microfluidics community and to help guide future research in the field. Full article
(This article belongs to the Special Issue Analysis, Design and Fabrication of Micromixers, Volume II)
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