RNA Probes OR Riboprobes - High specific, activity RNA probes or riboprobes may also be synthesized from DNA templates cloned in expression vector. This is achieved through RNA synthesized in vitro (on DNA inserted in vector) and labelled simultaneously employing specific RNA polymerase and labelled nucleotides which are supplied by commercial firms in a kit for riboprobe preparation.

RNA probes offer several advantages over DNA probes, since these are single stranded, and provide improved signal or hybridization blots. However, widespread presence of ribonucleases creates some problems in their preparation and use, because these ribonucleases will cause degradation of RNA which is synthesized.

Therefore, extreme care is, needed in the preparation of riboprobe, keeping all glassware ribonuclease free (no glassware should be touched with bare hands, because ribonucleases may be available on our skin).