Microarray targets

For a carbohydrate microarray, a glass slide is modified by the thiol group as solid support. Carbohydrates in the form of glycosylamines are converted into maleimide via a hydrocarbon tether chain and covalently bound to the glass surface by hetero-Michael addition reaction (Park and Shin, 2(X)2) between the thiol group and the maleimide moiety of the glycosyl derivative (Fignre 14.4C). 

In an alternative approach, photodeposition chemistry based on maskless array synthesizer (MAS) uses a maskless light projector as a virtual mask to fabricate microarrays. The virtual mask is an array of hundreds of thousands of individually addressable aluminum mirrors on a computer chip. These mirrors function as virtual masks that reflect the desired pattern of UV fight and are controlled by the computer. 

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Antibody microarrays are the most common target microarrays. Target microarrays consist of different proteins printed onto planar-solid surfaces (7,8). In general, these arrays have found several applications in clinical studies because they allow identification of specific protein profiles. One of the major drawbacks of antibody microarrays is the need for oriented immobilization of the capture reagent onto the surface in order to avoid steric hindrance with the specific proteins presented in the sample. Therefore, to solve this problem, several strategies have been described that implied that chemical groups promote orientation and avoid cross-linkers that can interact nonspecifically with the query protein. Another important disadvantage is the loss of activity of proteins upon immobilization (9—11). 

Target validation, to determine that a gene product is causative of disease symptoms or that activation of the target protein ameliorates disease symptoms. Agonist/activator or an inhibitor which may be therapeutic could be identified using microarrays... 

Spike-ins are usually RNA transcripts used to calibrate measurements in a DNA microarray experiment. Each spike-in is designed to hybridize with a specific control probe on the target array. Manufacturers of commercially available microarrays typically offer companion RNA spike-ins kits . Known amounts of RNA spike-ins are mixed with the experiment sample during preparation. Subsequently the measured degree of hybridization between the spike-ins and the control probes is used to normalize the hybridization measurements of the sample RNA. 

Chang YE et al. Microarray analysis identifies interferon-inducible genes and Stat-1 as major transcriptional targets of human papillomavims type 31. J Virol 2000 74 4174-4182. 

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