A Fluorescent detection method for copper ions based on a direct redox route and desk study of wax-printed paper-based probes. Issue 16 (12th April 2018)

• Record Type: Journal Article
• Authors: Li, Jiawei; Li, Pan; Bian, Minghong; Huo, Danqun; Hou, Changjun; Qin, Hui; Zhang, Suyi; Zhang, Liang
• Is Part Of: Analytical methods. Volume 10:Issue 16(2018)
• Page Start: 1895
• Page End: 1901
• Publication Date: 2018-04-12
• Subjects: Chemistry, Analytic -- Periodicals; Analytical biochemistry -- Periodicals; Chemical laboratories -- Standards -- Periodicals; 543.1905
• DOI: 10.1039/c8ay00372f
• Languages: English
• ISSNs: 1759-9660

Abstract

Abstract : A fluorescent detection method for copper ions based on a direct redox route and desk study of paper-based probes. Abstract : Cu 2+ plays an important role in various fundamental physiological processes in organisms. Although Cu 2+ probes have been developed, little research has focused on using a direct redox route to quench fluorescence for Cu 2+ detection. Herein, a simple, label-free, cost-effective, and sensitive fluorescence method has been developed for Cu 2+ detection. In the absence of Cu 2+ and presence of NH3 + and SCN −, H2 O2 was employed as an oxidant to corrode BSA–Au NCs, resulting in the disappearance of fluorescence. In contrast, in the presence of Cu 2+, red fluorescence was maintained because Cu(NH3 )6 2+ can decompose H2 O2 . Under optimal conditions, good linear correlation between the fluorescent response and Cu 2+ concentrations ranging from 5 to 1250 nM was obtained ( R 2 = 0.9938). Furthermore, this monitoring method has successfully been applied to real urine, tap water, and sorghum extract samples, demonstrating the potential for field applications. Based on this work, we successfully immobilized BSA–Au NCs on wax-printed paper to accomplish real-time field Cu 2+ detection. Fluorescence images were captured under UV light (365 nm), and R -values (red value of RGB color model) were analyzed. The obtained linear relationship between the R -value and the Cu 2+ concentration demonstrated the potential of this approach. The developed probe also showed satisfactory selectivity and excellent reproducibility. Although previous methods required a masking agent to protect against interference from increasing Hg 2+ concentration, Hg 2+ and other interfering ions had a near-negligible effect on results in the present work.