Colorimetric Electronic Tongue for Rapid Discrimination of Antioxidants Based on the Oxidation Etching of Nanotriangular Silver by Metal Ions

Abstract

We present a simple, rapid, and effe/ctive colorimetric sensor array (or colorimetric electronic tongue) for discrimination of antioxidants, which is based on the oxidation etching of triangular silver nanoparticles (TriAgNPs) by three metal ions (Se 2+ , Sn 4+ , and Ni 2+ ) as array's recognition elements and the inhibition of TriAgNP etching by antioxidants. Since highly reactive edges/tips of TriAgNPs are easier to be etched than other regions, the morphology of TriAgNPs undergoes a transition from nanoprism to nanodisk, accompanied by a color change from blue to yellow. The addition of diverse antioxidants inhibits TriAgNP etching in varying degrees, forming different etching morphologies with rainbowlike color. Surface plasmon resonance peak shift (Δλ) values of final TriAgNPs were captured as colorimetric signal outputs for further data processes. Linear discriminant analysis, hierarchical clustering analysis, heat map, etc. were adopted in the further data analysis process, showing the excellent discrimination ability of the sensor array for six antioxidants at 1 nM level. Moreover, selectivity experiments and practical application tests show that our sensor array had considerable selectivity and great potential in real samples.

Engineering single-atom catalysts toward biomedical applications

“…345 Inspired by the taste and olfaction responses, the cross-response sensor arrays have been designed to identify multiple antioxidants simultaneously by a unique recognition pattern. [346][347][348] The Fe-SACs with oxidase-mimicking activity were applied to fabricate a triple-channel colorimetric sensor array (Fig. 19d).…”

Single Probe-Based Chemical-Tongue Sensor Array for Multiple Bacterial Identification and Photothermal Sterilization in Real Time

“…In recent decades, the investigation has focused on developing biosensors for rapid and sensitive detection of bacteria. Though great achievements have been reached, most of the sensing systems usually can only detect one kind of bacteria and suffer from discriminating multiple bacteria. − Inspired by the mammalian olfactory system, a chemical nose-tongue strategy has attracted wide attention, − which provides an alternative way for high-throughput detection and identification of bacteria species. Based on the interaction between targets and a chemical nose-tongue sensor array, the obtained unique response pattern for multiple bacterial identification can be realized via linear discriminant analysis (LDA). − However, it is worthy of noting that the constructed sensor arrays usually involve several signal probes for generating the readout pattern, − which increases the complexity and cost of the detection.…”

Qualitative and quasi-quantitative monitoring of drinking water through the use of a smart electronic tongue

“…Although in the electronic tongue devices have been used various analytical principles such as optical, mass, frequency measurements, among others (Khan et al, 2016;li et al, 2019;Kovacs et al, 2020;Sehra et al, 2004;Aydemir and Ebeoglu, 2018). Devices based on potentiometric and voltammetric electrochemical measurements have been more widely accepted and have shown their effectiveness in the analysis of different types of beverages (Arrieta et al, 2019;Belugina et al, 2020;Totova and Nachev, 2020;Marx et al, 2017).…”