Microarray

Synonyms

DNA array; Protein array and cell array

Definition

Microarrays constitute highly parallel biosensors used in biomedical applications for studying a multitude of complex biological interactions simultaneously to determine the presence and/or amount (quantitation) of nucleic acids and proteins in biological samples, respectively, to investigate gene expression levels or for proteomics studies (e. g. in blood, cell extract, tissue extract). These miniaturised two-dimensional arrays contain a large number (hundreds up to hundreds of thousands) of different unique biological capture agents [nucleic acids (e. g. oligonucleotides, genes, gene fragments), proteins (e. g. antibodies)] on a solid substrate that are arranged in small chemical reaction areas (spots) in a predetermined spatial order (ranging from the hundreds of micrometre down to the sub-micrometre range). Typical substrates are glass, membranes, or silicon wafers.

The complex biological interactions are identified by the...