Fraunhofer Institute for Cell Therapy and Immunology, Branch Bioanalytics and Bioprocesses IZI-BBIn protein microarrays, proteins are applied and immobilised on modified slides. For this purpose, the corresponding proteins can either be produced recombinantly, from cDNA or expression banks, or protein microarrays can be produced from DNA microarrays using in vitro transcription / translation on demand.
The produced protein microarrays can be used for many different applications. Most often these microarrays are used to identify interactions. Besides protein-protein interactions, interactions between immobilized proteins with small molecules, e.g. ATP and drugs, the influence of co-factors, salinity and pH on interactions, with lipids and carbohydrates can be investigated.
The challenge in production is to ensure that all proteins are immobilised uniformly and as functionally as possible. Numerous different techniques are available for this purpose. They range from adsorption on nitrocellulose, covalent coupling e.g. to epoxy-modified surfaces or by click chemistry, to immobilization via affinity tags or antibodies.
Due to the variety of available technologies and years of expertise, many protein classes can be applied to a wide variety of surfaces and made available for analysis.