Quantitative analysis of thyroid-stimulating hormone (TSH) using SERS-based lateral flow immunoassay

•SERS-based laterl flow assay was used for the ultrasensitive detection of TSH in serum.•The LOD is two orders of magnitude more sensitive than that achieved from conventional LFIA.•This approach has strong potential feasibility in the early diagnosis of TSH-related diseases. We report the development of a surface-enhanced Raman scattering (SERS)-based lateral flow immunoassay (LFIA) sensor for the highly sensitive detection of thyroid-stimulating hormone (TSH) in clinical fluids. Here, Raman reporter-labeled gold nanoparticles (AuNPs) were used as SERS nano tags. Using this SERS-based LFIA test strip, the presence of TSH could be identified through a color change in the test line. In addition, quantitative evaluation of TSH was possible by monitoring the characteristic Raman peak intensity of SERS nano tags. The limit of detection (LOD) was estimated to be 0.025μIU/mL, which is approximately two orders of magnitude more sensitive than that achieved from the conventional colorimetric LFIA sensor based on the naked eye. Consequently, it is possible to diagnose hyperthyroidism as well as hypothyroidism since a TSH concentration lower than 0.5μIU/mL can be detected using this SERS-based LFIA detection technique. Therefore, this approach has strong potential feasibility for application in the early diagnosis of TSH hormone-related diseases.