Narong SarisutaPawinee Noomwong2024-02-132024-02-13200720072007Thesis (M.Sc. (Pharmaceutics))--Mahidol University, 2007https://repository.li.mahidol.ac.th/handle/20.500.14594/96963Pharmaceutics (Mahidol University 2007)The aims of the present study were to develop acyclovir nanoparticles for ocular drug delivery and to investigate the influence of formulation and process parameters on their physicochemical properties as well as in vivo transcorneal permeability. Various formulations of acyclovir-loaded nanoparticles with 20 and 40 mg of acyclovir per 18 mg of poly lactic-acid (PLA) and 500 mg of bovine serum albumin (BSA) were prepared by the direct precipitation method and desolation technique, respectively, at 2 and 4 ml/min pump rates to elicit precipitation of nanoparticles. The mean size of PLA and BSA nanoparticles measured by photon correlation spectroscopy (PCS) were in the range of 204- 249 nm and 125-132 nm, respectively. It was observed that the morphology of both acyclovir-loaded nanoparticles examined by scanning electron microscopy (SEM) were spherical in shape and uniform in size. Increased quantity of acyclovir added into the formulation would lead to significant improvement of drug entrapment efficiency for acyclovir-loaded PLA nanoparticles but conversely significant reduction for acyclovir-loaded BSA nanoparticles. However, the values of the loading capacity of both acyclovir-loaded PLA and BSA nanoparticles were within the same order of magnitude. It may be then concluded that both biodegradable polymeric (PLA) and protein (BSA) nanoparticles possessed the same entrapment ability although they are completely different in their natures. It was also found that the entrapment efficiency of both acyclovir-loaded nanoparticles would be significantly increased with the increasing solvent pump rate. For in vivo permeation study through rabbit cornea, acyclovir level in aqueous humor were monitored at 30, 60, 90 and 120 min after ocular administration. The results showed that both types of acyclovir-loaded nanoparticles could readily permeate through the cornea into aqueous humor, whose maximum acyclovir concentrations were reached within 30 min after administration and the drug concentrations could still be prolonged till 120 min passed. Nevertheless, the drug concentrations in aqueous humor of both acyclovir-loaded nanoparticles were still below the effective inhibitory concentration. The gel formulations incorporated with acyclovir-loaded PLA and BSA nanoparticles were prepared in order to increase the viscosity of the formulation and investigated for their in vivo transcorneal permeation in comparison with aqueous dispersions of nanoparticles. It was found that the drug concentrations of both gel formulations at 60 min after administration reached the effective viral inhibition level. Increase in viscosity of gel formulations of nanoparticles would not only prolong the residence time at site of action, but also delay the release of drug from the gel.xiii, 123 leaves : ill.application/pdfengผลงานนี้เป็นลิขสิทธิ์ของมหาวิทยาลัยมหิดล ขอสงวนไว้สำหรับเพื่อการศึกษาเท่านั้น ต้องอ้างอิงแหล่งที่มา ห้ามดัดแปลงเนื้อหา และห้ามนำไปใช้เพื่อการค้าNanoparticlesAcyclovirLactic AcidSerum Albumin, BovineMaster ThesisMahidol University