Highly Sensitive and Selective Colorimetric Sensor of Mercury (II) based on Layer-by-Layer Deposition of Gold/Silver Bimetallic Nanoparticles.

ABSTRACT: A new colorimetric sensor based on gold/silver bimetallic nanoparticles (Au-Ag BNPs) for the sensitive and selective detection of mercury (II) was developed. Gold nanoparticles (AuNPs) were synthesized by Turkevich method. The surface modification of AuNPs was modified by the layer-by-layer technique using poly(diallyl dimethylammonium chloride) which provided positively charged of AuNPs. Negatively charged silver nanoparticles (AgNPs) were synthesized by chemical reduction using poly(4-styrenesulfonic acid-co-maleic acid) as the stabilizing agent. The layer-by-layer assembly deposition technique was used to prepare Au-Ag BNPs of positively and negatively charged of AuNPs and AgNPs, respectively. The synthesized Au-Ag BNPs were characterized by a UV-visible spectrophotometer, zeta potential analyzer, FT-IR, TEM, XRD, and EDX. The Au-Ag BNPs sensor was able to detect mercury (II) in aqueous solution, visibly changing from brownish-orange to purple. The linear relationships of the UV-visible spectrometry demonstrate that the Au-Ag BNPs-based colorimetric sensor can be used for the quantitative analysis of mercury (II) in the range of 0.5-80 mg L-1, with the correlation coefficient, r2 = 0.9818. The limit of detection (LOD) of mercury (II) was found to be 0.526 + 0.001 mg L-1. The BNPs is also verified to have a good practical applicability for mercury (II) detection in the real samples.

SUBMITTER: Mathaweesansurn A 

PROVIDER: S-EPMC7583855 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature