水溶性, 結晶性薬剤の湿潤性に関する研究 (第7報)

抄録

Nicotinamide (NAA)-tartaric acid (TA) and NAA-urea mixture are considered to form least hygroscopic compound, and CRH was calculated even by the pre-equilibrium method under the experimental conditions by author. This value almost coincided with that by the saturation method. With NAA-L-ascorbic acid (LAA) mixture, CRH is coincident by both methods. The LAA-urea mixture is considered to form a compound but the X-ray diffraction analysis showed that it was simply a mixture. According to the X-ray diffraction of the solid phase, even when CRH by both method may coincident, it was found that the thermodynamic equilibrium is not always maintained between the component. The calculation equation of CRH in the IV report, is applicable to the mixture of forming complex. A decline in Vitamin C potency by moistening in NAA-LAA mixture, is considered to be prevented by forming complex beforehand but the experiment by the author was not the case.