Applications microfluidics-based biomedical devices

A fascinating approach is being investigated to exploit the Belousov-Zhabotinsky reaction, which induces autonomous oscillations in the redox potential of a medium, to drive spontaneous peristaltic motion of hydrogels by controlling their volume shifts (Argentiere et al, 2012). Murase et al (2008) 

Kara and Yoshida (2008), in an attempt to extend the application of these artifidal muscle-like actuators under biological conditions, synthesized a quar-temary copolymer which incorporated methacrylamidopropyltrimethylam-monium chloride as an oxidant supplier in addition to the aforementioned three monomers, so that self-oscillation could be achieved under physiological conditions where only malonic add is present. There is potential for these setf-osdUatmg gel actuators with tunable periodicity (Maeda et al, 2008) to be used for peristaltic micropumps and novel biomimetic appUcations. 

Both miniaturized analyte sensors and microsystems for drug delivery have been demonstrated, and the integration of both functionalities within one medical device is the next natural step. Smart polymer-based sensors, actuators, microvalves, micropumps, etc., can be combined in a single microfluidic system to construct medical devices with applications in diagnostics and/or treatment, and first attempts at developing such LOC devices are currently underway. 

Microfluidics represents a useful tool for POC diagnostics too. POC systems can permit the performance of rapid, reliable and inexpensive diagnostic tests without the need to move to a clinical laboratory (Sia and Kricka, 2008), with the possibility of using different biomarkers within one device for multiplexed immunoassays (Ng et al, 2010). Thus, they can help reduce the costs of screening for disease prevention, enhance patient observation to improve disease detection and improve treatment monitoring (Soper etal, 2006). 

As antigens manifesting a disease are often very dilute in body fluids, the first challenge in current immunoassays is to achieve clinically relevant 

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Hot-wire anemometers ( micro/nano anemometers) have been developed for a wide spectrum of applications from experimental fluid mechanics to aerospace engineering to measure physical parameters such as temperature, flow rates, and shear stress. The advent of microelectromechan-ical systems (MEMS) and nanoscale thermal sensors has provided an entry point to microfluidics, biomedical sciences, and micro-circulation in cardiovascular medicine. These MEMS and nanoscale devices are fabricated with semiconductor-based sensing elements which harbor the physical property of a resistor and have the dimension of one-tenth of a strand of hair. On the basis of the heat transfer principle, these resistant elements are heated by the Joule effect due to the passage of electric current. As the... 

Fujii, T., 2002. PDMS-based microfluidic devices for biomedical applications. Microelectron. Eng. 61-62, 907-914. 

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