Characterization of Solid Binary Systems of Efavirenz and Hydroxypropyl-β-Cyclodextrin

Efavirenz is a widely prescribed anti-retroviral drug that belongs to BCS class II and exhibit low and variable oral bioavailability due to its poor aqueous solubility and it requires enhancement in solubility and dissolution rate for increasing its oral bioavailability. The aim of this study was to increase the solubility of Efavirenz (EFA) by complexing it with Hydroxypropyl-β-cyclodextrin (HPβCD). Solid binary systems were prepared by co-grinding and microwave irradiation methods. The interaction of EFA with HPβCD was evaluated by Phase solubility studies, in vitro dissolution studies and different analytical techniques including Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). The apparent stability constant revealed EFA with HPβCD produces 1:1 M stoichiometric complex. The host guest interactions studied by FTIR and DSC confirmed true inclusion of EFA with HPβCD at 1:2 M. The Dissolution rates of EFA- HPβCD binary systems were faster when compared to physical mixture and pure drug. Overall the rank order of improvement in dissolution properties of Efavirenz with ratios is 1:2M > 1:1M and methods MW > CG > PM > Pure drug. One-way ANOVA suggest the DP60 and DE60 values were significantly higher (P<0.05) in solid binary systems prepared by microwave irradiation method when compared to co-grinding and its corresponding physical mixtures and pure drug.

Effects of l-menthol and its binary systems on the percutaneous penetration and the deposit effect of 5-fluorouracil / 中国临床药理学与治疗学

AIM: To study the effects of l-menthol and its binary systems on percutaneous penetration and deposit effects of 5-fluorouracil (5-FU). METHODS: Percutaneous absorption experiment was performed on the apparatus of isolated skin, penetrated amounts of different times of 5-FU were determined, the cumulate penetrated amounts and permeation rates and increased permeation times were calculated, and the deposit effect of 5-FU was investigated. RESULTS: L-menthol of different concentrations could significantly enhance the percutaneous penetration of 5-FU, its increased permeation times were 1.25 and 1.45 and 1.37 times respectively,and the action of 5-FU with 2% l-menthol was the strongest. 5-FU with 2% and 4% l-menthol had a marked deposit effect. When some kinds of enhancers were used alone or combined with l-menthol, the percutaneous penetration of 5-FU had a significantly increase. CONCLUSION: L-menthol and its binary systems can markedly promote the percutaneous penetration and the deposit effect of 5-FU.