A novel paper‐based microfluidic device and UV‐visible spectroscopy coupled method for the field detection and analysis of seized marijuana samples.

Cannabis is recorded to be the most used drug in the world. This causes a lot of difficulties for developing countries to curb the illegal cultivation, sale, and use of cannabis. The main psychoactive component of the cannabis plant is D9‐tetrahydrocannabinol (THC). The introduction of mobile forensic labs has greatly increased the testing efficiency of psychotropic substances, but the traditional methods of analysis might seem to be cumbersome for the individual experimenting with the scene of seizure. The incorporation of portable analytical devices in forensic field analysis is the approach in the right direction for the testing of drugs. In this paper, we introduce a paper‐based microfluidic device for the onsite detection of marijuana. The device comprises the fast blue B reagent (FBB) as the main reagent. The µPAD was used for the successful detection of seized marijuana. The µPAD‐based detection was combined with a UV‐Vis spectroscopic confirmation. The computational modeling of the absorbance spectra gave further insights into the product formation during the reaction of THC and FBB. This novel method helps in a faster analysis of marijuana, at a considerably lower cost; which is a great boost to the forensic community and the law enforcement authority. [ABSTRACT FROM AUTHOR]