title: Colorimetric detection of Cr (VI) based on the leaching of gold nanoparticles using a paper-based sensor.
abstract: Herein, we have developed a simple, sensitive and paper-based colorimetric sensor for the selective detection of Chromium (Ⅵ) ions (Cr (VI)). Silanization-titanium dioxide modified filter paper (STCP) was used to trap bovine serum albumin capped gold nanoparticles (BSA-Au NPs), leading to the fabrication of BSA-Au NPs decorated membrane (BSA-Au NPs/STCP). The BSA-Au NPs/STCP operated on the principle that BSA-Au NPs anchored on the STCP were gradually etched by Cr (VI) as the leaching process of gold in the presence of hydrobromic acid (HBr) and hence induced a visible color change. Under optimum conditions, the paper-based colorimetric sensor showed clear color change after reaction with Cr (VI) as well as with favorable selectivity to a variety of possible interfering counterparts. The amount-dependent colorimetric response was linearly correlated with the Cr (VI) concentrations ranging from 0.5µM to 50.0µM with a detection limit down to 280nM. Moreover, the developed cost-effective colorimetric sensor has been successfully applied to real environmental samples which demonstrated the potential for field applications.
authors: Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China.
authors: Jian-Feng
authors: JF
authors: Guo
authors: Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China. Electronic address: huodq@cqu.edu.cn.
authors: Dan-Qun
authors: DQ
authors: Huo
authors: Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China. Electronic address: yangmei@cqu.edu.cn.
authors: Mei
authors: M
authors: Yang
authors: Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China; National Key Laboratory of Fundamental Science of Micro/Nano-Device and System Technology, Chongqing University, Chongqing 400044, China.
authors: Chang-Jun
authors: CJ
authors: Hou
authors: Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China.
authors: Jun-Jie
authors: JJ
authors: Li
authors: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China.
authors: Huan-Bao
authors: HB
authors: Fa
authors: Liquor Making Bio-Technology & Application of Key Laboratory of Sichuan Province, Zigong 643000, China.
authors: Hui-Bo
authors: HB
authors: Luo
authors: National Engineering Research Center of Solid-State Brewing, Luzhou Laojiao Group Co. Ltd., Luzhou, Sichuan 646000, China.
authors: Ping
authors: P
authors: Yang
keywords: Colorimetric; Cr (VI); Gold nanoparticles; Non-aggregation; Paper-based