VALIDATION OF HUMAN BEHAVIOR REPRESENTATIONS

Fibrinogen is labeled with 99m Technetium by reducing pertechnetate at a pH of about 11-12 using a solution of stannous chloride in the presence of a base, then contacting the reduced pertechnetate with fibrinogen. Unwanted lower molecular weight impurities are removed; the labeled product suitably adjusted to a pH of 7-8 to form an injectable isotopic tracer solution.