Nanolabels for biosensors based on lateral flow immunoassays

The COVID-19 outbreak was an important turning point in the development of a new generation of biosensing technologies. The synergistic combination of an immunochromatographic test (lateral flow immunoassays, LFIA) and signal transducers provides enhanced sensitivity and the ability to quantify in the rapid tests. This is possible due to the variety of nanoparticles that can be used as reporter labels. In this review, we first present an overview on the principles of a LFIA and its different formats. We analyze cutting-edge work on these platforms based on different types of nanoparticles used as labels and on the highly sensitive transducers to which they can be coupled. The works discussed herein have a beneficial impact on the fields of clinical analysis, food safety or environmental control, thus highlighting the relevance of the biosensors. Last, we provide insights into the barriers that need to be overcome when designing laboratory prototypes accessible to the society.