Journal of Microbial & Biochemical Technology

Abstract

A Readable Chromatic Biosensor with a Tunable Detection Threshold

Chiao-Hsiu Tsai, Ying-Jhan Hong, Jing-Huei Huang, Pin Chang and Tri-Rung Yew

Rapid and readable chromatic detection of antigen is essential for medical and clinical applications as they are inexpensive, portable and simple in operating process. In addition, results from chromatic biosensors can be easily readout without any equipment or instrument collocation. However, only a few studies accomplished the goal by detecting the antigen via this strategy; even though, the detection range is still narrow and only could be applicate on some specific disease identification. Still, most of the chromatic biosensors are continuing color transition and hard to identify the disease at critical point. Therefore, it is essential to develop a wide-detecting ranged or detecting range tunable chromatic biosensor revealing considerably color-change for numerous diseases recognition. This article presents a detection range tunable readable chromatic biosensor for antigen detection, demonstrated by the detection of human serum albumin (HSA). First, the HSA sample was pre-conjugated to chitosan to form HSAchitosan complex, then, the HSA-chitosan complex was utilized to synthesize Ag NPs. According to the color shown by the synthesized Ag NPs, 0.01-0.3 mg/ml HSA sample could be determined. Furthermore, the detection range could be adjusted to 0.001-0.1 or 0.1-1 through decreasing or raising the chitosan-conjugating concentration, showing the potential for more disease identification application.