What is a “probe”?
Biomolecule of known identity (e.g. nucleic acid) which is immobilized on the slide. (Cf. conventional blotting methods, where probe = marked molecule, not immobilized). Nomenclature of probes and targets: The first publication dealing with microarray analysis (Schena et al., 1995) uses the term target to describe the immobilized DNA molecule onto the microarray substrate and probe to describe the sample that will be analyzed. This naming is based on the traditional northern blot nomenclature, where the term probe describes the immobilized sample, that will be analyzed. In principle the intention of northern blot analysis are the same as of microarray experiments, that is to measure the expression level of genes. However, the inversion of the physical locations of probes and targets led to some confusion within the microarray community. Therefore, you will always find some researchers, that are using probe to describe the immobilized DNA, whereas others describing with this term the sa
