The InsituStain is a system designed to semi-automate many commonly used techniques in the laboratory. Its main focus is in situ hybridisation and immunohistochemistry which are automated in a way that closely mimicks the manual protocol. In addition, the InsituStain can fully automate gel staining and blot processing, including recovery of antibodies into cooled positions. In summary, the InsituStain can automate any technique based on repeated liquid exchange in a tub.

In a typical in situ hybridization protocol, the InsituStain automates the following manual steps:

• Rehydration of specimens or slides
• Permeation with proteinase K or detergent
• Postfixation
• Prehybridization
• Hybridization with one probe
• Post hybridization washes
• Blocking and incubation with a single antibody
• All washing steps

As all samples in the incubation tub are processed equally, steps requiring individual treatment of the samples, such as incubation with different probes or antibodies have to be performed outside the machine. Nevertheless, projects such as mutant screens utilizing in situ hybridization or immunohistochemistry using a single probe or antibody (i.e. requiring the same treatment for all samples) can be fully automated with the InsituStain.

The unit is based on a peristaltic pump and a 13-channel valve for liquid exchange. A shaking platform that can be heated or cooled is used for incubation of the samples. The 12 buffer positions include two cooled positions of 50 ml each or one of 250 ml and two heated 250 ml positions. Method development is done on an easy to use PC software package, and the unit is operated by an internal processor that runs the programmed method from a MiniSD memory card.