Screening protein molecules for a particular biological activity sometimes requires the purification of hundreds of proteins. Often many constructs, from several 100 to a 1000, are screened before the lead candidate is found. What is needed is a rapid and reliable way to purify these proteins. Here we describe the simultaneous purification of 10 fusion proteins utilizing a novel instrument, the BioOptix 10. (c) 2006 Elsevier Ltd. All rights reserved.