Plaisen S, Cheewasedtham W, Rujiralai T. Robust colorimetric detection based on the anti-aggregation of gold nanoparticles for bromide in rice samples.
RSC Adv 2018;
8:21566-21576. [PMID:
35539899 PMCID:
PMC9080936 DOI:
10.1039/c8ra03497d]
[Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 05/28/2018] [Indexed: 01/13/2023] Open
Abstract
Inorganic bromide (Br−) is an important contaminant ion as it can originate from the overuse of illegal methyl bromide as a fumigant in stored rice samples. Herein, we developed a simple and highly sensitive colorimetric sensor for bromide ion detection in rice samples. The sensor is based on the anti-aggregation of gold nanoparticles (AuNPs) by Br− in the presence of Cr3+, which made the method more selective than other typical aggregations of nanoparticles. The AuNPs underwent an aggregation process as a result of the coordination of Cr3+ and the carboxylate group of a citrate ion stabilized the AuNPs, resulting in a red-to-blue color change. When Br− was pre-mixed with the AuNPs and Cr3+ was added, the solution color changed from blue to red with an increase in the Br− concentration. The anti-aggregation process can be detected with the naked eye and monitored using UV-vis spectrophotometry. The linear calibration curve ranged between 0.31 and 3.75 μM Br− with a low LOD and LOQ of 0.04 and 0.13 μM. The recovery was excellent, ranging from 79.9–92.2% with an RSD of less than 4.0%. The good inter-day and intra-day precisions were 2.9–6.4% and 3.1–7.1%, respectively. The developed sensor has proved to provide a robust method for Br− detection in rice samples.
In this work, we developed a AuNP colorimetric sensor for the facile, sensitive and selective detection of bromide ions in rice samples.![]()
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