Rapid Testing Prototype for Amphetamine Abuse Using Fluorescent Polymeric Nanoparticle-Based LFA Systems

This study presents the design, synthesis, and validation of a fluorescent polymeric nanoparticle (FNP) synthesized for the first time in the literature integrated into a lateral flow assay (LFA) system and establishes a proof-of-concept for its application as a functional fluorescent label in point-of-care (POC) diagnostics. The combination of fluorescent polymeric nanoparticles (FNPs) and lateral flow assays (LFAs) brings many advantages to the field of point-of-care testing (POCT), such as excellent sensitivity and quantitative measurements. The continuous increase in drug addiction, particularly amphetamine (AMP), requires a change of methodology for quick and accurate detection. We developed an FNP-based LFA system for the rapid and sensitive detection of AMP, one of the important abuse drugs today. AMP is a powerful central nervous system stimulant that is widely used owing to its euphoric effects and poses a significant threat to public health and safety. For this reason, FNP, which has been produced as a promising label for on-site and sensitive detection, is thought to make great contributions to the literature because its features allow precise and reliable measurements even in complex matrices. This provides valuable information for future design improvements. Poly[4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4,5-b’]dithiophen-2,6-diyl)-(thiophene-3-carbaldehyde-2,5-diyl) (p-TAlBDT) polymer synthesized for the first time in this study was used in the structure of FNPs, and its performance was tested for the first time in LFA. The limit of detection (LOD) determined by this LFA test format for AMP is 0.73 μg/mL (n = 3). Finally, this study offers a transformational solution to the widespread problem of AMP abuse through the integration of FNP into LFA systems. The presented detection system is intended to provide innovative advantages to LFA systems, offering a powerful alternative to the traditional competitive assay format used for the analysis of small molecules. The use of FNPs also reduces the limit of quantification capability of LFA assays in the competitive format. This study contributes not only to the field of substance abuse detection but also highlights the greater potential of fluorescence-based measurements, adding to the advantages of POC diagnostics with a promise to combat the public health challenges of drug addiction and improve public health outcomes.