EXHIBIT 4.1 CALYPTE BIOMEDICAL CORPORATION COMMON STOCK PURCHASE AGREEMENT OCTOBER 17, 1997 NOTICE TO PURCHASERS IN ALL STATES: IN MAKING AN INVESTMENT DECISION INVESTORS MUST RELY ON THEIR OWN EXAMINATION OF THE ISSUER AND THE TERMS OF THE OFFERING,...Common Stock Purchase Agreement • October 21st, 1997 • Calypte Biomedical Corp • Laboratory analytical instruments • California
