Selective Detection of Anions Using Gold Nanomaterial−Based Fluorescent Probes

• Main Authors: Shih-Chun Wei, 魏士鈞
• Other Authors: Pang-Hung Hsu
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/24499612000614833011

碩士 === 國立臺灣海洋大學 === 生物科技研究所 === 101 === The selective sensing of important anions, such as halide(Cl−, Br−, and I−), sulfide(S2−), nitrite(NO2−)and cyanide(CN−)ions are highly significant because they are widely distributed and play important roles in both environmental and life sciences. To date, many strategies have been proposed for the detection of those anions in aqueous solutions.But selectivity is a problem. We developed two simple, rapid, and cost−effective fluorescent nanosensors, one featuring bovine serum albumin labeled with fluorescein isothiocyanate(FITC)−capped gold nanoparticles(FITC−BSA−Au NPs), for the selective sensing of cyanide(CN−)and iodine(I−)ions in high−salinity solutions and edible salt samples. The other one is the nanoclusters synthesized by BSA in high pH solution(BSA−Au NCs), for the detection of nitrite(NO2−)in water samples. The FITC−BSA−Au NPs operated on a basic principle that I− and CN− deposited on the surfaces of the Au NPs or the etching of Au NPs induced the release of FITC molecules or FITC−BSA into the solution, and thus restored the florescence of FITC. We employed FITC−BSA to protect the Au NPs from significant aggregation in high−salinity solutions. In the presence of masking agents selectively detect I− and CN− in water samples and detection of I− in edible salt samples, respectively. On the other hand, we demonstrate BSA−Au NCs−based probes for the detection of NO2− by oxidation of nanocluster and the probes synthesized after different days have different detection limit and structure. We also employed our BSA−Au NCs/NCM −based probes for the detection of NO2− in water and urine samples. This simple, rapid, and cost−effective sensing system appears to demonstrate immense practical potential for the detection of anions in real samples.