Nanomaterial- and micromaterial-based immunoassays

Immunoassays have undergone a long application history in disease diagnostics, which play a major role for public health in the past four decades. However, traditional immunoassay methods are limited by some stubborn problems, such as limited sensitivity, complicated operation, time-consuming, being unable to multiplex, and on-site detection. The developments of material science and biology technology bring immunoassays new vigor. Among them, the introduction of nano- and micromaterials has a significant effect on immunoassays, benefiting from their unique physical properties (e.g., high surface-to-volume ratio, active molecule dynamism, and distinct optical-electronic-magnetic characteristics). Intensive studies have been reported to exhibit the improvements of immunoassays in sensitivity, specificity, cost, reaction rate, and miniaturization induced by nano- and micromaterials in the last two decades. This critical chapter reviews the recent innovative strategies and applications of nanomaterial- and micromaterial-based immunoassay, especially regarding colorimetric, electrochemical, and fluorescent assays.