Comparison of dual-target and mono-target strips for the detection of fentanyl and xylazine

The research operates within the established paradigm of competitive lateral flow immunoassay (LFIA) as a tool for rapid, qualitative chemical detection. This study applies the accepted principles of LFIA to the specific public health and harm reduction problem of drug checking. It focuses on comparing and refining existing technology (mono-target strips) with a newer iteration (dual-target strips) for detecting fentanyl and xylazine, thereby extending the application of the current paradigm without challenging its core tenets.

This paper is classified as Normal Science because it engages in "puzzle-solving" within an accepted scientific framework. The researchers use standard methodologies—evaluating limits of detection, cross-reactivity, and performance in various matrices—to compare mono-target and dual-target test strips. The goal is not to question the validity of lateral flow immunoassays but to characterize and incrementally improve their application for a pressing societal need. This work refines the use of an existing tool for a new, complex problem, which is a hallmark of research conducted during the Normal Science stage of a paradigm.