Molecular Devices acquires Transfluor imaging technology from Xsira Pharmaceuticals

Sunnyvale, Calif., March 9, 2005 - Molecular Devices Corporation (Nasdaq: MDCC) today announced that it has acquired the complete portfolio of Transfluor® technology assets from Xsira Pharmaceuticals, Incorporated (formerly Norak Biosciences, Incorporated) for $11 million cash. This transaction strengthens Molecular Devices' leadership position as a provider of tools for both imaging and G-protein coupled receptor (GPCR) assays, two of the most important and fastest-growing areas of drug discovery.

Transfluor® technology, comprising proprietary assays that operate on imaging platforms such as Molecular Devices' Discovery-1 and ImageXpress® systems, offers a robust way to visualize key cellular events and to detect receptor activation. Because of its nearly universal applicability to all types of GPCRs, the leading class of drug targets, Transfluor® technology has become a popular tool for drug discovery.

Commenting on the transaction, Dr. Michael Sjaastad, Molecular Devices' Director of Marketing, Imaging, said, "Transfluor® technology is a perfect fit for Molecular Devices and further confirms our commitment to provide novel imaging solutions to the drug discovery market. With a product portfolio that includes Transfluor® technology, our Fluorometric Imaging Plate Reader (FLIPR®), and reagents, Molecular Devices now offers best-in-class screening solutions for every major type of GPCR target."

Xsira Pharmaceuticals, which commercialized Transfluor® technology based on research conducted at Duke University, will now focus on its own drug discovery program using a license to Transfluor® technology granted by Molecular Devices. "We are excited to see Molecular Devices, a world-class bioanalytical tools company, step into the role of commercializing Transfluor® technology and managing its further evolution," said Roger Blevins, Pharm.D., President and Chief Executive Officer of Xsira. "Transfluor® technology has proven to be an enabling system for GPCR-based drug discovery at Xsira and many other pharmaceutical companies, and we are confident that Molecular Devices is the best company to ensure its continued success."

Molecular Devices plans to begin licensing Transfluor® technology and related materials to customers in the second quarter of 2005. Parties interested in Transfluor® technology should contact their Molecular Devices sales representative.

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