Study On PMMA Microfluidic Immunoassay Chip System Based On Magenetic Beads

With the development of analytical chemistry, biology, electronics and computer technology, more and more instruments are used in clinical laboratory science and made it develops rapidly. As a new branch of clinical laboratory science, point of care testing (POCT) is formed recently. POCT use miniaturized instruments and simple methods to analysis all kinds of sample near patient bed, at home or in the field. As it is convenient , fast and has high accuracy, POCT will be the main force of clinical laboratory science in the future. The high develop speed of POCT will bring new opportunity to clinical laboratory science.Immunoassay is one of the most important biological analytic methods, which is used widely in clinical diagnosis, pharmic analysis, environment monitor and biological research due to its'high specificity and sensitivity. But general immunoassay mothods has some shortcomings, such as time-consuming, handle-complexity. These drawbacks restrict their application in POCT. Although commercial automatic immune analyzer has high efficiency and high accuracy, but the analyzer is hugeness and expensive, so it is only used in some large-scale hospitals. It is very important to develop miniaturized and portable automatic immune analyzer which can be used in small-scale hospitals and POCT.Microfluidic chips, a novel miniaturized analytic platform, use micromachining technology to construct a liquid circuit system composed of various mini functional components. It can process one or series analyse on a chip, so fast and high throughput assay can be achieved. Microfluidic chips show great advantages in immunoassay. First it can shorten analysis time and improve analysis efficiency, some microfluidic chip can fulfill detection, separation or other complicated operations within seconds. Second it can reduce reagent and sample consume, we can use few microlitre reagent to complete analysis through microfluidic chip, so it reduce analysis costs. At last, It is easily to be integrated and portable, which can be conveniently used in POCT. But, nowadays, most microfluidic chip can be used only once, which brings high analytic costs. And, there lies great system error between different chips due to the restriction of micromachining technique. Furthermore, in most microfluidic chips, antibodies are linked directly in the microchannels, which may cause denaturalization of antibodies, non-special adsorption and reduction of analytic sensitivity.