The thin green line : A novel lateral flow assay platform for point of care diagnostics
Lateral flow assays (LFA) represent one of the most important tools in point-of-care-diagnostics (POC) and therefore play a crucial role in disease control and food safety. However, the underlying technology of LFAs features severe limitations. High limits of detection and the absence of suitable molecular recognition elements (MRE) for small analyte molecules, highly toxic, and non-immunogenous targets limit their field of applications. At the same time the high demand for LFAs calls for sustainable and green solutions to assure the sufficient supply in the future. Here, these problems are tackled by introducing the first LFA system featuring nano-bio-conjugates (NBC) consisting of laser-generated nanoparticles and aptamers. The conjugation and functionality of the NBCs was analyzed via physiochemical methods (spectroscopy, color analysis, LFA functionality testing). Conjugates featuring moderate surface coverages provided the best functionality. The elemental surface composition does affect the functionality of the NBCs, yet they represent robust detection units that operate over a broad range of varying alloy compositions. It was possible to demonstrate NBC functionality und LFA conditions when recovered hexaethylenglycol (HEGL)-spacer-aptamers from previous conjugation processes were used, which represents a great example of improved atom economy. All findings were fused into one functional test system for ampicillin detection. This new type of LFA upholds the high standards of POC-diagnostics, while introducing aspects of green chemistry. These findings might contribute to aptamer-LFAs finding their niche in the vast and growing field of POC-diagnostic tools and help LFAs to take the next steps towards green technology.