Highly selective and flexible silver nanoparticles-based paper sensor for on-site colorimetric detection of paraquat pesticide

• Published in: RSC advances Vol. 14; no. 39; pp. 28844 - 28853
• Main Authors: Bhandari, Sanjeev, Parihar, Vijay Singh, Kellomäki, Minna, Mahato, Mrityunjoy
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 04.09.2024; The Royal Society of Chemistry
• Subjects: Chemistry; Chitosan; Cost analysis; Flexible components; Fourier transforms; Infrared spectroscopy; Nanocomposites; Nanoparticles; Onsite; Paraquat; Pesticides; Portable equipment; Reproducibility; Sensors; Silver; Spectrum analysis
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d4ra04557b

Paper-based sensors or paper-based analytical devices (PADs) have recently emerged as the cost-efficient, and portable, on-site detection tools for various biological and environmental analytes. However, paper-based sensors often suffer from poor selectivity. Here, a single-step paper-based flexible sensor platform has been developed for the on-site detection of paraquat (PQ) pesticide in real samples, utilizing chitosan and citrate-capped silver nanoparticles integrated with a flexible paper. The nanocomposite paper film was thoroughly characterized using UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The composite paper platform demonstrated a color change with a reaction time within a few minutes (6–7 min) in the presence of PQ pesticide. The trace level PQ pesticide has been detected with a limit of detection (LOD) of 10 μM and a linear range (LR) of 10–100 μM. The sensor shows 3× more selective signal towards PQ pesticide compared to other similar pesticides. The relative standard deviation (RSD) was found to be 5% for repeatability, 4% for reproducibility, 2% for interference, and 3.5% for real sample analysis, indicating high precision sensing and within the WHO limit of RSD (20%). The present work will open up new avenues for the advancements in flexible paper sensors; cost-effective, portable, on-site sensors, and sustainable device development.