Smartphone-integrated colorimetric and microfluidic paper-based analytical devices for the trace-level detection of permethrin

Permethrin is a pyrethroid pesticide and insect repellent that prevents mosquito-borne infections like dengue and malaria in tropical areas. This work describes a new colorimetric sensor based on metronidazole-stabilized silver nanoparticles (MTZ-AgNPs) for the first rapid, sensitive, and selective permethrin detection. The MTZ-AgNPsbased colorimetric sensor has a limit of detection (LOD) of 0.0104 & mu;M and a limit of quantification (LOQ) of 0.0348 & mu;M, respectively. The sensor is further integrated with smartphone and microfluidic fabrication of paperbased analytical devices (& mu;PADs) for real-time and on-site detection of permethrin. Under optimal settings, no potential environmental contaminants interfere with permethrin detection, confirming its high selectivity. Finally, the practical applicability of sensors is confirmed in real tomato and apple extract samples. The US environmental protection agency's recommended UPLC method validated the detection efficiency of the proposed colorimetric sensor. The % recoveries from UPLC and MTZ-AgNPs suggest that the present sensor can quantitatively analyze permethrin in real samples.

Automated summary

This work presents a new colorimetric sensor that can rapidly, sensitively, and selectively detect permethrin using metronidazole-stabilized silver nanoparticles (MTZ-AgNPs). The sensor has a limit of detection (LOD) and a limit of quantification (LOQ) of 0.0104 μM and 0.0348 μM, respectively. It has been successfully integrated with smartphone and microfluidic fabrication of paper-based analytical devices (μPADs) for real-time and on-site detection of permethrin.