Liposomes are one of the most attractive particles in different industries, especially pharmaceutical applications. The main reasons for such a desire for liposomes are nontoxicity, small size, the ability to encapsulate and carry biological components, and finally biocompatibility and biodegradability. The present study aims to simulate the active electrohydrodynamic-based micromixer for the high-throughput formation of nanoscale liposomes. The micromixer consists of two inlets for de-ionized water and one inlet for ethanol with lipid particles. Two configurations of asymmetric electrodes, namely, longitudinal and the array of electrodes, were introduced and examined. Electrodes were placed at the bottom of the mixer, and a direct current electrical field was applied to them. Generated chaotic advection inside the microchannel by the electrical field and, consequently, increasing surface-to-volume ratio is the main reason for the increase in the formation of liposomes. These configurations of electrodes cause the liposome formation occurs at very low voltages, which is the most advantage of the proposed micromixer. The Taguchi method as a statistical method of design of experiment (DOE) was utilized to reduce the number of required simulations. The simulations showed that case 6 had the best mixing index of 0.586 among the studied models. Also, according to the DOE results, the best possible design was found and simulated and a mixing index of 0.743, which has a 5.3% error in comparison to the predicted results.

Receptor-based biosensors often suffer from slow analyte diffusion, leading to extended assay times. Moreover, existing methods to enhance diffusion can be complex and costly. In response to this challenge, we presented a rapid and cost-effective technique for fabricating concave magnetic-responsive hydrogel discs (CMDs) by straightforward pipetting directly onto microscope glass slides. This approach enables immediate preparation and customization of hydrogel properties such as porosity, magnetic responsiveness, and embedded particles and is adaptable for use with microarray printers. The concave design increased the surface area by 43% compared to conventional hemispherical hydrogels, enhancing diffusion rates and accelerating reactions. By incorporating superparamagnetic particles, the hydrogels become magnetically responsive, allowing for stirring within reagent droplets using magnets to improve mixing. Our experimental results showed that CMDs dissolved approximately 2.5 times faster than hemispherical ones. Numerical simulations demonstrated up to a 46% improvement in diffusion speed within the hydrogel. Particles with lower diffusion coefficients, like human antibodies, benefited most from the concave design, resulting in faster biosensor responses. The increased surface area and ease of fabrication make our CMDs efficient and adaptable for various biological and biomedical applications, particularly in point-of-care diagnostics where rapid and accurate biomarker detection is critical.

Hydrogel-based biosensors are commonly used in diagnostic applications. However, their performance remains constrained by slow analyte diffusion within polymer matrices, particularly when larger biomolecules are involved. Concave hydrogel geometries present a promising solution to enhance diffusion rates through increased surface area. However, the interfacial dynamics governing their formation must be studied. In this research, we investigated the interfacial dynamics that influence the formation of concave hydrogel discs fabricated by a simple pipetting method. We characterized the fluid interactions occurring during droplet deposition of alginate and CaCl₂ solutions. A three-phase flow model incorporating confocal microscopy validation was employed to simulate time-dependent interfacial behaviors. Concave hydrogel discs fabricated with alginate-first deposition exhibited 83% larger surface area compared to hemispherical counterparts at a CaCl₂: alginate volume ratio of one. Increasing the volume ratio further enhanced both surface area and diameter, though this highlighted limitations for microscopy-based detection. According to our results, reaction speed in alginate concave hydrogel discs can be controlled by varying the volume of CaCl₂ solution while keeping the volume of alginate solution constant, which changes the surface area while maintaining constant hydrogel volume.

Liposomes are one of the most attractive particles in different industries, especially pharmaceutical applications. The main reasons for such a desire for liposomes are nontoxicity, small size, the ability to encapsulate and carry biological components, and finally biocompatibility and biodegradability. The present study aims to simulate the active electrohydrodynamic-based micromixer for the high-throughput formation of nanoscale liposomes. The micromixer consists of two inlets for de-ionized water and one inlet for ethanol with lipid particles. Two configurations of asymmetric electrodes, namely, longitudinal and the array of electrodes, were introduced and examined. Electrodes were placed at the bottom of the mixer, and a direct current electrical field was applied to them. Generated chaotic advection inside the microchannel by the electrical field and, consequently, increasing surface-to-volume ratio is the main reason for the increase in the formation of liposomes. These configurations of electrodes cause the liposome formation occurs at very low voltages, which is the most advantage of the proposed micromixer. The Taguchi method as a statistical method of design of experiment (DOE) was utilized to reduce the number of required simulations. The simulations showed that case 6 had the best mixing index of 0.586 among the studied models. Also, according to the DOE results, the best possible design was found and simulated and a mixing index of 0.743, which has a 5.3% error in comparison to the predicted results.