Single domain antibodies in the development of immunosensors for diagnostics.

Scientific advances in nanotechnology and nanoscience have enabled stability optimization and signal amplification in immunoassays by taking advantage of unique properties of nanomaterials. Biosensors based on antibodies and their fragments, also called immunosensors, are compact tools capable of providing refined antigen detection capacity. Different immunoassays that utilize these molecules for biorecognition have been used as diagnostic tools. In this regard, camelid single domain antibodies fulfill several requirements, such as nanometric size, high affinity, specificity, solubility, stability, biotechnological versatility, and low cost of production, constituting an important source for the development of immunodiagnostic devices. In this review, the main technological advances involving this specific class of molecules, as well as their major biotechnological applications will be addressed, with emphasis on their use as biosensors applied to diagnostics in human health.