title: A plasmonic ELISA for the naked-eye detection of chromium ions in water samples.
abstract: Here, we describe the development of a triangular silver nanoprism (AgNPR) etching-based plasmonic ELISA for the colorimetric determination of Cr(III) levels in environmental water samples. This involved the creation of a novel signal generation system (substrate reaction solution) for a competitive ELISA in which hydrogen peroxide (H2O2) is used to etch triangular AgNPRs, inducing a change in color. This is achieved by controlling the H2O2concentration that remains after degradation by catalase, which is conjugated to the secondary antibody of the ELISA. Because the degree of color change and the shift in the absorption spectrum of the substrate reaction solution are closely correlated with the Cr(III) concentration, this plasmonic ELISA can be used not only for the quantification of Cr(III) concentrations ranging from 3.13 to 50 ng/mL, with a limit of detection (LOD) of 3.13 ng/mL, but also for the visual detection (indicated by a color change from blue to mauve) of Cr(III) with a sensitivity of 6.25 ng/mL by the naked eye. Therefore, the plasmonic ELISA developed in this work represents a new strategy for heavy metal ion detection and has high potential applicability in resource-constrained areas. Graphical Abstract Schematic diagram of triangular silver nanoprism etching-based signal generation system.
authors.affiliation: Department of Bioengineering, Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering, Jinan University, Guangzhou, Guangdong, 510632, China.|Medical Genetic Centre, Guangdong Women and Children Hospital, Guangzhou, Guangdong, 510010, China.
authors.forename: Cuize
authors.initials: C
authors.lastname: Yao
authors.affiliation: Department of Bioengineering, Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering, Jinan University, Guangzhou, Guangdong, 510632, China.
authors.forename: Shiting
authors.initials: S
authors.lastname: Yu
authors.affiliation: Department of Bioengineering, Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering, Jinan University, Guangzhou, Guangdong, 510632, China.
authors.forename: Xiuqing
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Bioengineering, Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering, Jinan University, Guangzhou, Guangdong, 510632, China.
authors.forename: Ze
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Department of Bioengineering, Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering, Jinan University, Guangzhou, Guangdong, 510632, China.
authors.forename: Jiajie
authors.initials: J
authors.lastname: Liang
authors.affiliation: Department of Bioengineering, Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering, Jinan University, Guangzhou, Guangdong, 510632, China.
authors.forename: Qiangqiang
authors.initials: Q
authors.lastname: Fu
authors.affiliation: Department of Bioengineering, Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering, Jinan University, Guangzhou, Guangdong, 510632, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Xiao
authors.affiliation: Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, Jinan University, Guangzhou, Guangdong, 510632, China. tjiangtj@jnu.edu.cn.
authors.forename: Tianjiu
authors.initials: T
authors.lastname: Jiang
authors.affiliation: Department of Bioengineering, Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering, Jinan University, Guangzhou, Guangdong, 510632, China. tyjaq7926@163.com.
authors.forename: Yong
authors.initials: Y
authors.lastname: Tang
keywords: Chromium ion; Colorimetric; Plasmonic ELISA; Triangular silver nanoprism