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A four-channel paper microfluidic device with gold nanoparticles and aptamers for seized drugs

NCJ Number
Analytical Biochemistry Volume: 595 Dated: 2020
Date Published

This note describes a four-channel paper microfluidic device (μPAD) that uses gold nanoparticles (AuNPs) as colorimetric sensors and specifically tailored aptamers to capture a set of targeted drugs, including cocaine, codeine and methamphetamine. 


The design uses salt-induced aggregation of AuNPs to produce a color change that indicates the presence of target analytes. In the absence of the targets, the aptamers bind to AuNPs, preventing aggregation. This μPAD was developed by optimizing the concentrations of aggregating agents, AuNPs and aptamers. The resultant device is sensitive and specific, producing a positive result upon detection of the target analyte. (publisher abstract modified)

Date Published: January 1, 2020