Zinyemba E, Morton D J
Department of Pharmacy, University of Zimbabwe, Mount Pleasant, Harare.
J Clin Pharm Ther. 1991 Dec;16(6):477-81. doi: 10.1111/j.1365-2710.1991.tb00338.x.
The stability and bioavailability of benzylpenicillin ophthalmic solutions were determined at pH 5, 6, 6.5, 7 and 8 in citrate buffer. The stability of benzylpenicillin solutions stored at room temperature was greatest at pH 6.6-7 while at 2-4 degrees C stability was greatest at pH 6.5. The uptake by corneal and aqueous humour of benzyl [14-C] penicillin into ovine eyes was greatest at a pH of 6.5, which indicates that for optimum stability and bioavailability benzylpenicillin ophthalmic solutions should be prepared in citrate buffer at pH 6.5. Under these conditions the stability of the refrigerated preparation is acceptable for a normal treatment period.
在柠檬酸盐缓冲液中，于pH值5、6、6.5、7和8的条件下测定了苄青霉素眼用溶液的稳定性和生物利用度。室温下储存的苄青霉素溶液在pH 6.6 - 7时稳定性最佳，而在2 - 4℃时，pH 6.5时稳定性最佳。苄基[14-C]青霉素在羊眼中角膜和房水的摄取在pH 6.5时最高，这表明为了获得最佳稳定性和生物利用度，苄青霉素眼用溶液应在pH 6.5的柠檬酸盐缓冲液中制备。在这些条件下，冷藏制剂的稳定性在正常治疗期内是可以接受的。
