Study on the Preparation of Melatonin Solid Lipid Nanoparticles and Their Transcutaneous Absorption in vitro / 中国药房

OBJECTIVE： To prepare Melatonin solid lipid nanoparticles （MT-SLNs）， and to investigate in vitro transcutaneous absorption characteristics of them in isolated skin of mice. METHODS： Using melatonin （MT） as model drug， glycerin sorbate as oil phase， poloxamer 188 （F188） as emulsifier， MT-SLNs was prepared by melt-emulsion method. The morphology of MT-SLNs was observed by TEM； the particle size distribution of MT-SLNs was measured by laser particle size analyzer， and the infrared spectrum characteristics were measured by infrared spectroscopy. The entrapped efficiency and drug loading amount were determined by HPLC and ultrafiltration centrifugation method. The transcutaneous absorption characteristics in vitro of MT-SLNs and MT raw material were compared using Franz diffusion cells method. RESULTS： The formulation of MT-SLNs included 2.5 mg/mL MT raw material， 25 mg/mL glycerin sorbate and 1％F188. The obtained MT-SLNs were spherical， and no aggregation was observed. Average particle size was （67.88±0.17）nm， and polydispersity index was 0.188±0.001. The characteristic absorption peaks of N—H stretching and bending vibration were not found in infrared spectra， and the characteristic absorption peaks of C—H stretching vibration of benzene ring shifted red to 1 750 cm－1. The entrapped efficiency and drug loading amount of MT-SLNs were （87.54±5.31）％ and （8.42±0.78）％. The transcutaneous absorption behavior of MT-SLNs and MT raw material conformed to zero-order kinetics release rule. The steady-state transmission rate of MT-SLNs [（31.71+2.78） μg/（h·cm2）] was significantly higher than that of its raw material [（10.32±3.24） μg/（h·cm2）]， and its lag time [（0.17±0.01） h] was significantly shorter than that of its raw material [（1.57±0.37） h] （P＜0.01）. CONCLUSIONS： Prepared MT-SLNs have small particle size and distributed evenly， and can promote in vitro transcutaneous absorption.

Formulation Optimization of Indomethacin-loading Solid Lipid Nanoparticles by Box-Behnken Response Surface Methodology / 中国药房

OBJECTIVE:To optimize the formulation of indomethacin-loading solid lipid nanoparticle(SLN). METHODS:Us-ing indomethacin as model drug,glyceryl behenate as oil phase,poloxamer 188 and polyethylene glycol-12-hydroxystearic acid as emulsifier,with turbidity,entrapment efficiency and drug loading amount as index,Box-Behnken response surface methodology was used to optimize the amount of oil phase,emulsifier-oil phase ratio,drug-oil phase ratio. The physicochemical properties of SLNs were characterized by SEM and DSC. RESULTS:The optimal formulation was as follows as oil phase of 0.91%,emulsifier-oil ratio of 1∶1,drug-oil phase ratio of 1∶5. The turbidity,entrapment efficiency and drug loading amount of prepared nanoparticle were 1 025-1 030 NTU,98.94%-99.08%,2.43%-2.46%,respectively;particle size and polydispersity index(PDI)were 181.5-182.3 nm and 0.340-0.341(n=3). The results of DSC showed that indomethacin was not present in crystalline state dispersed into SLNs. CONCLUSIONS:The optimal formulation is screened successfully,and indomethacin-loaded SLNs have been prepared.

Study on the quality standards of Yi Li Kang tablets / 国际中医中药杂志

Objective To establish the quality control standard for Yi-Li-Kang tablets. Methods Astragalus membranaceus and Herba Epimedh were identified by TLC. The content of Icariin was determined by HPLC. Results The linear range of Icariin was 0.288～2.016 μg. The average recovery was 100.83%, and RSD was 1.82 (n=5). Conclusion The method is simple, accurate and reliable, which can be used to control the quality of Yi-Li-Kang tablets.

Optimization of thermosensitive in situ gel system containing berberine hydrochloride for ocular use / 中草药

Objective To prepare a thermosensitive in situ gel system containing berberine hydrochloride for ocular use. Methods The in situ thermosensitive gel system of berberine hydrochloride was prepared by Poloxamer 407 (P407) and Poloxamer 188 (P188) as thermosensitive materials,the formulation was optimized by determining solution-gelation conversion temperature by using stirring method. The content of berberine hydrochloride was determined by HPLC. Results The gelation temperature of in situ thermosensitive gel containing berberine hydrochloride formulations lowered as the P407 concentration increased,as the P188 concentration increased gradually the gelation temperature initially increased to maximum and then decreased. The gelation temperature all increased after simulated tear fluid (STF) dilution. The fitted equation was established for the gelation temperature with the concentration of Poloxamer solutions after diluted by STF. An optimized formulation by Design-Expert software was freely flowing liquid at 29.7 ℃ and convert to a firm gel at 34.5 ℃ after STF diluted. Conclusion In situ thermosensitve gel system complies with the requirement for ophthalmic application and shows great potential in ocular application.