Reference

Drug migration into soft gelatin capsule shells and its effect on in-vitro availability

Drug migration into soft gelatin capsule shells and its effect on in-vitro availability. Armstrong, N. A.; James, K. C.; Pugh, W. K. L. (Inst. Sci. Technol., Univ. Wales, Cardiff CF1 3NU, UK). J. Pharm. Pharmacol., 36(6), 361-5 (English) 1984. CODEN: JPPMAB. ISSN: 0022-3573. DOCUMENT TYPE: Journal CA Section: 63 (Pharmaceuticals) Anal. of the shells and contents of soft gelatin capsules contg. acetomenaphthone [573-20-6], ephedrine [299-42-3], 4-hydroxybenzoic acid [99-96-7] or phenobarbitone [50-06-6], dissolved in isopropyl myristate [110-27-0], revealed that the percentage of solute taken up by the shells increased with increasing aq. soly. of the substrate. Thus no acetomenaphthone, which has a negligible aq. soly., was found in the shells, in comparison with 92% of the 4-hydroxybenzoic acid, which has a significant soly. in water. Uptake was not affected by the soly. in iso-Pr myristate. The effect of the oily solvent was studied using blends of 1-octanol [111-87-5] and iso-Pr myristate in which either 4-hydroxybenzoic acid or phenobarbitone were dissolved. Solute release shows that both release and migration can be predicted from a knowledge of the aq. soly. of the solute and its partition coeff. between water and the nonpolar solvent. Samples of capsules contg. 4-hydroxybenzoic acid in iso-Pr myristate were withdrawn at various stages of the manufg. process, and the distributions between shell and contents noted. Most of the transer took place, while the capsules were being dried in rotating basket driers, and at this point 67% of the acid had migrated. This increased to 92% during tray drying, and remained so for at least 6 mo after manufacturer.

Kinetics of drug decomposition

Kinetics of drug decomposition. LXXV. Thermal stability of certain K vitamins in solid phase. Pawelczyk, Ewaryst; Marciniec, Barbara (Inst. Drugs, Sch. Med., Poznan 60-780, Pol.). Acta Pol. Pharm., 40(5-6), 561-7 (Polish) 1983. CODEN: APPHAX. ISSN: 0001-6837. DOCUMENT TYPE: Journal CA Section: 63 (Pharmaceuticals) Section cross-reference(s): 22 The thermal stability of vitamins K decreased in the order: K4 [573-20-6] > K3 [58-27-5] (sol. form) > K3 > K2 [11032-49-8] and K1 [84-80-0]. Detailed kinetic investigations carried out for K4 and K3 by accelerated aging revealed a zero-order reaction involving 2 mols. for both. Under normal storage conditions, the decompn. time t10% was 124 days for vitamin K3 and 170 yr for vitamin K4. The use of vitamin K4 in pharmaceutical prepns. of K-type vitamins was strongly recommended.