Recent advances of upconversion nanoparticles-based lateral flow assays for point-of-care testing

Lateral flow assays (LFA), as the most commonly used commercialized point-of-care testing (POCT), has been limited by the detection accuracy for decades. To address this challenge, the improvement of detection sensitivity and quantitative ability become necessary. Therefore, increasing new fluorescent LFA have been developed and attracted lots of attentions. Wherein, the upconversion nanoparticles (UCNPs)-based LFA stand out, due to its advantages of high photostability, great robustness and long shelf life. In this review, we summarized the recent advances in UCNPs-based LFA. First, we summarized the luminescent properties of UCNPs and described its relationship with LFA properties. Next, the common signal enhancement, signal readout manner and multiplex detection strategies in UCNPs-based LFA were reviewed to meet diverse detection requirements. Following, the wide applications in food safety, disease diagnosis, and environmental monitoring were discussed. Finally, the current challenges and perspectives on the future development of UCNPs-based LFA were also provided.