Gold nanoparticle–based lateral-flow immunochromatographic biosensing assays for the diagnosis of infections

Infections cause concern for mankind, and sometimes their diagnosis may take much time. Owing to its high sensitivity, rapidity, and specificity, the immunochromatographic assay (ICA) is used widely to diagnose infections. The use of the ICA for this purpose makes it possible to detect dangerous diseases early, prevent their progress, strongly reduce the treatment cost and mortality, and increase life expectancy. One promising ICA format involves the use of gold nanoparticles. Here we present the principles and history of ICA use for the diagnosis of infections and discuss the prospects for using gold nanoparticles in the ICA. We present data on the methods used to make and conjugate gold nanoparticles and on the effect of particle size and shape on ICA sensitivity. We discuss the prospects for using the ICA to diagnose bacterial and viral infections, and we review instrumental methods for quantifying ICA results. Finally, we discuss the prospects for using the gold nanoparticle–based ICA in the diagnosis of infections.