Detection of hydrogen sulphide in human blood plasma on a microfluidic platform

We report a microfluidic method for rapid measurement of H2S in human blood plasma using a fluorescence-based probe, Dansyl Azide (DNS-Az). The study revealed that the fluorescence assay required a mixing time of 2 min, incubation time of 5 min, a pH of 7.1, and performing the test within 10 min of sampling at room temperature. The proposed device shows a linear correlation (R2≥0.95) and an excellent match with the conventional spectrometric method. We have also measured the endogenous concentration of H2S in human blood plasma and which was found to lie in the range 75μM -125μM.