An alternative solid phase ChIP affinity matrix

Porvair Filtration Group working in collaboration with the Department of Biological Sciences, University of Essex, UK has produced an alternative, high performance Solid Phase Affinity Matrix for Chromatin Immunoprecipitation (ChIP) assays.

The research at Essex University evaluating the new BioVyon - Protein A material in ChIP assays is published in the May 2011 issue of Analytical Biochemistry.

Over the past eight years - researchers at the University of Essex and Porvair Filtration Group have pioneered techniques to chemically functionalise the surface of microporous High Density Polyethylene (HDPE) to enable its use in a growing number of new biochemical applications.

Chemical functionalisation of Porvair Filtration's HDPE material (BioVyon) can endow it with internal surface properties than can be individually configured to capture and separate target species out of difficult mixtures. This has opened up many possibilities in the field of biosciences where molecules of interest such as DNA, RNA, proteins etc can be selectively pulled out of complex mixtures of biological origin. Chromatin immunoprecipitation (ChIP) is an important technique in the study of DNA/protein interactions.

The ChIP procedure, however, has limitations in that it is lengthy, can be inconsistent, and is prone to non-specific binding of DNA and proteins to the bead-based solid-phase matrices that are often used for the immunoprecipitation step.

Researchers at the University of Essex and Porvair Filtration have examined the utility of a new matrix for ChIP assays, BioVyon Protein A, a solid support based on porous polyethylene. In ChIP experiments carried out using two antibodies and seven DNA loci, the performance of BioVyon Protein A was significantly better, with a greater percentage of DNA pull-down in all of the assays tested compared with bead-based matrices, Protein A Sepharose, and Dynabeads Protein A. Furthermore, the rigid porous disc format within a column made the BioVyon matrix much easier to use with fewer steps and less equipment requirements, resulting in a significant reduction in the time taken to process the ChIP samples.

In summary, BioVyon Protein A provides a column-based assay method for ChIP and other immunoprecipitation-based procedures; the rigid porous structure of BioVyon enables a fast and robust protocol with higher ChIP enrichment ratios.

For more information, visit  www.chromatrap.com or www.porvairfiltration.com

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