Sjödin L, Viitanen E
Department of Drugs, National Board of Health and Welfare, Uppsala, Sweden.
Pharm Res. 1987 Jun;4(3):189-94. doi: 10.1023/a:1016495709237.
A sensitive radioreceptor assay was developed for pharmaceutical insulin formulations with the use of rat liver membranes and 125I-insulin. The addition of unlabeled insulin or insulin analogues inhibited the binding of 125I-insulin to the receptors in a concentration-dependent way. Insulin concentrations between 3 x 10(-9) and 3 x 10(-8) M were used for a three-point assay which fulfilled pharmacopoeial statistical requirements for validity of the assay. The coefficient of variation for five assays was 4%. Potency estimates of insulin preparations obtained with the radioreceptor assay correlated well with corresponding estimates from in vivo assays. Both assays also gave similar potency readings for insulin preparations that were partly degraded during storage at elevated temperatures, but the radioreceptor method was more precise.
利用大鼠肝细胞膜和125I胰岛素开发了一种用于药物胰岛素制剂的灵敏放射受体测定法。添加未标记的胰岛素或胰岛素类似物会以浓度依赖的方式抑制125I胰岛素与受体的结合。胰岛素浓度在3×10（-9）至3×10（-8）M之间用于三点测定，该测定满足了药典对测定有效性的统计要求。五次测定的变异系数为4%。通过放射受体测定法获得的胰岛素制剂效价估计值与体内测定法的相应估计值相关性良好。对于在高温储存期间部分降解的胰岛素制剂，两种测定法也给出了相似的效价读数，但放射受体法更精确。
