Scientists in Japan have discovered a way to eliminate the false positives that can occur when using high-throughput screening methods. 

Hideaki Hioki and colleagues at the Tokushima Bunri University have come up with a labelling reagent and on-bead colour assay for use in water that they say prevents the misleading results that can be created when using combinatorial methods to screen peptides for specific interactions.

Instead of conventional water soluble dyes, which can selectively bind to peptides in solution to give artificial results, Hioki used a Trinder reagent to label the target molecules. According to Hioki, this reagent does not bind to peptides in solution. The reagent itself is colourless but turns purple with the addition of 4-aminoantipyrine, hydrogen peroxide and peroxidase. 'This technique will enable a variety of peptide libraries to precisely screen with a target in water,' said Hioki. 'The sensitivity is comparable with a conventional colour assay.' 

Helma Wennemers, an expert in combinatorial chemistry at the University of Basel, Switzerland, said the method will be very useful. 'Hioki has provided a solution to the crucial issue of applying on-bead screenings of split-and-mix libraries in aqueous solution,' said Wennemers.   

Elinor Richards