Biosensors Based On Gold Nanoclusters

Gold nanoclusters is a kind of novel nanomaterials, with sizes (<2nm) near theFermi length of conduction electrons, it has some special properties. Gold nanoclustershave a high luminescence intensity, good stability and biocompatibility, they are oftenused as a fluorescent probe to detect target substances. Most of the detections are basedon either the enhancement or the quenching of the fluorescent. This article is based onthe fluorescence quenching effect from targets, established a series of biosensingsystems.In the first part of this paper, we synthesized gold nanoclusters with bovine serumalbumin (BSA) as the template. Based on trypsin hydrolysis the template, we establish amethod for the detection of trypsin. And we study the interaction between the trypsinwith the soybean trypsin inhibitor (STI), establishing a method for detecting trypsininhibitor.In the second part, we synthesized trypsin-stabilized fluorescent gold nanoclusters.It was found that sulfide interacted with the nanoclusters, which could result insignificant fluorescence quenching. With this quenching effect, a fluorescence ofdetecting sulfide sensor was developed. Furthermore, persulfate was found to beeffective to remove the quenching of sulfide, and this interaction was adopted for anindirect analysis of persulfate.