Immobilization of DNA on microarrays

Microarrays are new analytical devices that allow the parallel and simultaneous detection of thousands of target compounds. Microarrays, also called DNA chips, are widely used in gene expression, the genotyping of individuals, point mutations, detection of single nucleotide polymorphisms, and short tandem repeats. Microarrays have highly specific base-pair interactions with labeled complementary strands, which makes this technology to a powerful analytical device for monitoring whole genomes. In this article, we provide a survey of the common microarray manufacturing methods, from the selection of support material to surface structuring, immobilization and hybridization, and finally the detection with labeled complementary strands. Special attention is given to the immobilization of single strands, since fast chemical reactions, the creation of homogeneous surface functionalities as well as an oriented coupling are crucial pre-conditions for a good spot morphology and microarrays of high quality.