A facile cellulosic paper-based colorimetric sensor for detection of perchlorate using albumin-conjugated gold nanoparticles

Abstract

Perchlorate, a prevalent and dangerous contaminant, is being increasingly found in untreated wastewater from urban areas and industrial discharges, as well as in unmonitored surface and groundwater sources. The urgent need for the creation of straightforward, efficient, and environmentally friendly sensing techniques to detect perchlorate in water. Cellulosic paper-based sensors show great promise as sustainable tools for detecting chemical pollutants. The study aimed to develop and evaluate the effectiveness of a paper-based sensor for detecting perchlorate levels in water samples. The approach showcased a reliable perchlorate colorimetric detection method, integrating digital smartphone imagery with paper-based sensors. The sensor employs a colorimetric assay that relies on the modification of gold nanoparticles with egg albumin protein, a material derived from biological sources. A digital smartphone facilitates on-site colorimetric data collection, and image processing methods are used to determine the presence of perchlorate in water samples based on these digital pictures. The grayscale color intensity derived from digital images is utilized for quantitative analysis. Comprehensive parametric evaluations were conducted to examine the stability and selectivity of the color intensities obtained from the sensor. The limits of detection and quantification are established at 2.86 µg/L and 9.55 µg/L, respectively. This study delivers a facile, highly sensitive, and cost-effective technique for the detection of perchlorate, particularly advantageous in industrial and rural settings where advanced detection devices are scarce.