BioSource Appoints New President and Chief Executive Officer.

Business Editors

CAMARILLO, Calif.--(BUSINESS WIRE)--Sept. 26, 2001

BioSource International Inc. (Nasdaq:BIOI) today announced the appointment of Leonard M. Hendrickson as president and chief executive officer of the Camarillo-based biotechnology company.

Hendrickson has been a director of BioSource since 1993 and is currently the president and director of Isotope Products Laboratories, a subsidiary of Eckert & Ziegler AG, a German biomedical company whose shares are publicly traded on the Frankfurt NeuerMarkt in Germany.

Hendrickson replaces James H. Chamberlain, the founder and former president and chief executive officer of the company, who returned from retirement last May to serve as interim CEO. Hendrickson will continue to serve as a director of the company.

"We are very excited to have Len on board leading BioSource as its CEO," stated Jean-Pierre Conte, the company's interim chairman. "Len has the unique skill set we feel is necessary to carry out our new strategies and to position BioSource for the future. Although we conducted an extensive search to fill the position, Len was a leading candidate from the start."

"This is an exciting opportunity for me," Hendrickson said. "BioSource is a dynamic biotechnology company wonderfully positioned to play a significant role in the burgeoning genomic and proteomic marketplace. My first job will be to strategically position the company for accelerated top-line growth. I look forward to working with the management team to increase the growth rate of BioSource and gain a larger share of our marketplace."

Hendrickson has served in his present role as president and director of Isotope Products Laboratories since 1992. From 1990 to 1992, Hendrickson was the principal consultant for Microchemics, a marketing and business development consulting firm that he founded. He also held several management positions with Amersham Pharmacia Biotech, a major provider of biotechnology systems, products and services.

Hendrickson holds a bachelor of science degree in chemical engineering from the University of Pennsylvania and a master of business administration degree from American University in Washington, D.C.

Hendrickson will begin his employment on Oct. 15, 2001. Chamberlain will continue in his interim CEO role up to Hendrickson's hire date. Conte will continue as the company's interim chairman.

BioSource International Inc. is a broad-based life sciences company focused on providing integrated solutions in the areas of functional genomics, proteomics and drug discovery through the development, manufacturing, marketing and distribution of unique biologically active reagent systems that facilitate, enable and accelerate pharmaceutical development and biomedical research.

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