A ratiometric fluorescence nanosensor for highly selective and sensitive detection of selenite. Issue 15 (31st May 2016)

• Record Type: Journal Article
• Authors: Chen, Linfeng; Tian, Xike; Zhao, Yuan; Li, Yong; Yang, Chao; Zhou, Zhaoxin; Liu, Xiangwen
• Is Part Of: Analyst. Volume 141:Issue 15(2016)
• Page Start: 4685
• Page End: 4693
• Publication Date: 2016-05-31
• Subjects: Chemistry, Analytic -- Periodicals; 543
• DOI: 10.1039/c6an00740f
• Languages: English
• ISSNs: 0003-2654

Abstract

Abstract : We herein developed a ratiometric fluorescent nanosensor for accurate and on-site sensing of SeO3 2− by linking the recognition molecules 3, 3′-diaminobenzidine (DAB) onto the surface of carboxyl group modified CdTe@SiO2 . Abstract : The instant and on-site detection of selenium still remains a challenge for environmental monitoring and medical prevention. We herein developed a ratiometric fluorescent nanosensor for accurate and on-site sensing of SeO3 2− by linking the recognition molecule 3, 3′-diaminobenzidine (DAB) onto the surface of carboxyl group modified CdTe@SiO2 . The fluorescence of DAB on the surface of silica nanospheres could be selectively and efficiently enhanced by SeO3 2− through a surface chelating reaction between DAB and SeO3 2− . Thus, in the presence of SeO3 2−, the nanosensor would show two characteristic fluorescence emissions of Se-DAB and CdTe QDs under a single excitation wavelength. The selectivity and the optimal conditions for the detection of SeO3 2− were carefully investigated. The ratio of F 530 / F 635 linearly increased with increasing SeO3 2− concentration in the range of 0 to 2.5 μM and the detection limit reaches as low as 6.68 nM (0.53 ppb). This developed nanosensor has the capability of on-site detection in an aqueous system without any separation step. The Se concentrations in selenium-rich food were detected and the results were consistent with the values determined by ICP-AES.