What Are Microarrays?

Microarrays are highly parallel biosensors. Their sensor effect is based on a chemical reaction between molecules with a lock and key principle.

When producing a microarray, the different catching molecules are put on at defined pitch on the substrate. The reaction between the catching molecules and a complex mixture of molecules is the actual 'measurement'. Caught molecules can be detected after washing off any surplus material.

Microarrays are usually analysed using fluorescence techniques. The molecules in the complex mixture are 'equipped' with fluorescence molecules for later detection.

In the detection equipment (scanner) an image is made of the fluorescence signal intensity, which is translated in a characteristic fluorescence image. The position of the catching molecule in its array gives information of the identity of the caught molecule.