A microfluidic micromixer fabricated using polydimethylsiloxane-based platform for biomedical applications

© MIDEM Society. Personalised dosing microfluidic devices have great potential in transforming current biomedical treatment into more efficient and patient-tailored using lab-on-chip designs. One of the current challenges in manufacturing microfluidic devices is designing suitable mixers, at the microscale level, with intricate geometrical dimensions. The study aimed at designing micromixers using polydimethylsiloxane-based platform and investigated their performance and potential applications in biomedical devices. New microchip-like structure was fabricated and consisted of two inlets and one outlet. A mould was fabricated based on polydimethylsiloxane platform and the new design was examined in terms of mixing patterns. The flow-mixing process was tested for efficiency and robustness. The novel design showed consistent intricate dimensions suggesting fabrication method was robust and precise. The mixing ability of the micromixers showed semi-circular flow with efficient mixing at low liquids pressure (< 50 mbar) suggesting ability to mix fluids with various viscosities. Accordingly, the newly designed micromixers using polydimethylsiloxane-based platform with two inlets and one outlet have promise in biomedical fluid-mixing applications

Nanofibre optic force transducers with sub-piconewton resolution via near-field plasmon–dielectric interactions

Ultrasensitive nanomechanical instruments, including the atomic force microscope (AFM)(1-4) and optical and magnetic tweezers(5-8), have helped shed new light on the complex mechanical environments of biological processes. However, it is difficult to scale down the size of these instruments due to their feedback mechanisms9, which, if overcome, would enable high-density nanomechanical probing inside materials. A variety of molecular force probes including mechanophores(10), quantum dots(11), fluorescent pairs(12,13) and molecular rotors(14-16) have been designed to measure intracellular stresses; however, fluorescence-based techniques can have short operating times due to photo-instability and it is still challenging to quantify the forces with high spatial and mechanical resolution. Here, we develop a compact nanofibre optic force transducer (NOFT) that utilizes strong near-field plasmon-dielectric interactions to measure local forces with a sensitivity of <200 fN. The NOFT system is tested by monitoring bacterial motion and heart-cell beating as well as detecting infrasound power in solution.National Science Foundation [ECCS 1150952, ECCS-1542148]; University of California, Office of the President [UC-LFRP 12-LR-238415]; California Institute of Regenerative Medicine [RT3-07899]; National Institutes of Health [R01EB021857]; National Institute on Aging of National Institutes of Health [AG028709]6 month embargo; Published online: 15 May 2017This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]