EXHIBIT 2.1 STOCK PURCHASE AGREEMENT BY AND AMONG BIOSOURCE INTERNATIONAL, INC., QUALITY CONTROLLED BIOCHEMICALS, INC., THE STOCKHOLDERS OF QUALITY CONTROLLED BIOCHEMICALS, INC., JAVELLE PHARMACEUTICALS, INC., AND THE STOCKHOLDERS OF JAVELLE...Stock Purchase Agreement • February 22nd, 1999 • Biosource International Inc • In vitro & in vivo diagnostic substances • California
