[The Homogeneous immunocofactor method of determining insulin]. / Gomogennyi immunokofaktornyi metod opredeleniia insulina.

An immunocofactor quantitative method of measuring insulin in solution was developed. The method uses antibody competitive binding of free and NAD labeled insulin. The NAD-insulin conjugate was obtained by covalent binding of the C(6)-aminogroup modified cofactor with insulin by means of soluble carbodiimide. To determine the NAD-insulin conjugate, which was not bound with antibodies, in the presence of antibodies and free insulin, an enzymic system of the cofactor regeneration with conjugated substrates of horse liver alcohol dehydrogenase, cyclohexanol and p-nitroso-N,N-dimethyl aniline, was employed. The sensitivity of insulin assay was about 5.10(-7) M.