A colorimetric probe to determine Pb²⁺ using functionalized silver nanoparticles

Abstract

A simple and sensitive colorimetric method for the determination of Pb(2+) ions in aqueous samples was developed using 1-(2-mercaptoethyl)-1,3,5-triazinane-2,4,6-trione (MTT) functionalized silver nanoparticles (MTT-AgNPs). The Pb(2+) ion acted as the metal center of the coordination complex, which formed N-Pb(2+)-O coordination bonds with the MTT-AgNPs, shortening the interparticle distance, and inducing aggregation of the MTT-AgNPs. This aggregation resulted in a dramatic color change from yellow to dark blue. Using this methodology, the concentration of Pb(2+) ions in environmental samples could be quantitatively detected with the naked eye or by using UV-vis spectrometry. Also, we found that the selectivity and sensitivity of detection were noticeably improved in the pH range of 7-8, at which a more obvious color change was observed. The absorption ratios (A625/A395) of the modified AgNP solution exhibited a linear correlation with Pb(2+) ion concentrations within the linear range of 0.1-0.6 μg mL(-1), and the limits of detection in tap and pond water were 0.02 and 0.06 μg mL(-1), respectively. This cost-effective sensing system allows for the rapid and facile determination of Pb(2+) ions in aqueous samples.

Silver Nanoparticles as Colorimetric Sensors for Water Pollutants

“…The selectivity and sensitivity were noticeably improved in the pH range of 7-8, at which a more obvious color change was observed. The sensor exhibited a linear correlation with Pb (II) ion concentrations within the linear range of 0.1-0.6 µg/mL, and the limits of detection in tap and pond water were 0.02 and 0.06 µg/mL, respectively [142].…”

“…Tables 2 and 3 present some of the results obtained in the last years in the field of colorimetric optical sensors based on AgNPs for heavy metal ions and pesticides. AgNPs@Durenta erecta~23 ± 4 (FE-SEM) Cr (VI) 10-100 ppm 0.1 ppm [136] AgNPs@3MPS 4.1 ± 0.4 (TEM) Co (II) 0.5-2.0 ppm - [112] AgNPs@3MPS 4.1 ± 0.4 (TEM) Ni (II) 0.5-1.5 ppm - [112] AgNPs@1-amino-2-naphthol-4-sulfonic acid 12 (DLS) Cd (II) 1-10 µM 87 nM [139] AgNPs@ Octamethoxy resorcin arene tetrahydrazide 5 (TEM) Cd (II) 0-10 µM 10 nM [140] AgNPs@Chalcone carboxyl acid~7 (TEM) Cd (II) 0.227-3.18 µM 0.13 µM [141] AgNPs@1-(2-mercaptoethyl)-1,3,5-triazinane-2,4,6-trione 10 (TEM) Pb (II) 0.1-0.6 µg/mL 0.06 µg/mL (tap water) [142] AgNPs@Gluconate 9.57 ± 2 (TEM) Pb (II) 0.5-2.0 µM 0.2029 µM [143]…”

Development of an Analytical Method for the Determination of Lead Based on Local Surface Plasmon Resonance of Silver Nanoparticles

“…The limit of detection and the linear dynamic range of the proposed method for the lead are comparable with other methods. [20][21][22][23][24][25][26][27][28][29] However, in comparison to the solid phase extraction-colorimetry, LSPR technique is faster.…”

Highly Sensitive Colorimetric Assay for Determining Fe3+Based on Gold Nanoparticles Conjugated with Glycol Chitosan

“…Recently, numerous fluorescence sensors and chemosensors have been reported for the detection of metal ions; these sensors have several advantages, such as ease of use, high sensitivity, low-cost, and enabling of on-site monitoring [7–16]. Colorimetric nanoparticle assays have also been widely used to monitor metal ions because of their cost-efficiency and applicability for on-site monitoring, as opposed to other methods [17, 18]. Advances in nanoscience and nanotechnology have led to the development of new nanoparticle assays for Fe 3+ ions detection such as Cu or Au nanoclusters [19, 20], etching [21, 22], graphene quantum dot [23], and carbon dot [24] assay methods.…”