Uropathogenic Bacteria Identification and Antibiotic Susceptibility Testing on a Microfluidic Chip
A microfluidic chip assay was described for bacteria identification and antibiotic susceptibility test( AST). Filter paper pads were embedded in arrayed microchambers,with immobilized antibiotics and chromogenic medium. By taking advantage of the polyvinylidene fluoride( PVDF) membrane based valves,urine sample introduced was distributed in individual chambers without cross contamination. The simultaneous analysis of multiple bacteria was achieved by using the culture chamber array design. The identification of a bacterium was based on its specific colorimetric result. The density of a bacterium was determined by real-time monitoring color intensity in the chamber,and its susceptibility to an antibiotic was determined relying on the lowest antibiotic concentration that inhibited the colorimetric reaction. A set of three common uropathogenic bacteria were selected as models to test the microfluidic approach. Our results showed that the developed microfluidic assay was able to complete bacteria identification and the six-antibiotic AST in 18 h. In comparison with the conventional method,the microchip method showed a coincidence of 94. 1% and 93. 9%with regard to bacteria identification and AST,respectively. The developed microfluidic approach is simple and rapid,thus hold the potential to serve as a powerful tool for bacterial analysis under conditions of poor medical resource.