Design and fabrication of self-calibration colorimetric/fluorescence/SERS tri-modal optical sensor for highly rapid and accurate detection of mercury ions in foods
Jinxin Chen, Cheng Zhang, Lunzhao Yi, Fengmin Duan, Ying Gu, Kun Ge, Xuejing Fan
Abstract
The improvement of detection accuracy without loss of rapidity and sensitivity by optical sensors in complex food analysis is still full of challenges owing to the matrix interference. Herein, a novel and simple self-calibration colorimetric/fluorescence/surface-enhanced Raman spectroscopy (SERS) tri-modal optical sensor based on aminated Rhodamine 6G (R6G-NH 2 ) was developed for highly rapid, sensitive, and accurate detection of Hg 2+ in food samples. The high recognition specificity of R6G-NH 2 for Hg 2+ can be achieved through the metal chelation interaction between Hg 2+ and -NH 2 , -COOH groups in R6G-NH 2 with formation of R6G-NH 2 -Hg 2+ -R6G-NH 2 complex. The DFT and FDTD simulations were adopted to confirm the theoretical feasibility in Hg 2+ detection by tri-modal optical. Under the optimum conditions, the analytical method based on self-calibration tri-modal optical sensor for Hg 2+ detection was established with promising properties (rapidity, linearity, linear range, LOD, and LOQ), providing a strategy in rapid, selective, sensitive, and accurate detection for food safety. Herein, a novel and simple self-calibration colorimetric/fluorescence/surface-enhanced Raman spectroscopy (SERS) tri-modal optical sensor was designed and developed for highly rapid, sensitive, and accurate detection of Hg 2+ in food samples. • The R6G-NH 2 probe with high specificity for Hg 2+ was fabricated. • The self-calibration colorimetric/fluorescence/surface-enhanced Raman spectroscopy (SERS) tri-model optical sensor was developed. • The self-calibration function endows promising detection accuracy. • Rapid, sensitive, selective, and accurate analysis of Hg 2+ in foods.