ABSTRACT
OBJECTIVE：To study the distri bution and targeting characteristics of Apigenin nanosuspension （AP-NPs）in mice. METHODS：AP-NPs was prepared with ultrasound microprecipitation. Kunming mice were randomly divided into apigenin （AP） solution group and AP-NPs suspension group ，with 45 mice in each group. The mice were given relevant medicine intragastrically （80 mg/kg）；blood sample of eyeball 500 μL were collected before medication（0 h）and 0.25，0.5，1，2，4，6，8，10 h after medication. After the last blood collection ，the mice were sacrificed and their heart ，liver，spleen，lung，kidney and brain tissues were taken. After protein precipitation with methanol ，HPLC method was adopted for determining plasma and tissues. The determination was performed on Shimadzu ODS-SP column with mobile phase consisted of methanol-water （70 ∶ 30，V/V）at the flow rate of 1.0 mL/min. The detection wavelength was set at 340 nm，and column temperature was 35 ℃. The sample size was 20 μL. The concentration of AP in different samples was calculated according to standard curve，main pharmacokinetic parameters （AUC，cmax）of AP and the ratio of peak concentration （ce），relative uptake rate （RUE），uptake ratio and its change value were calculated with DAS 2.0 software and Excel 2010 software；the tissue distribution and targeting characteristics of AP were analyzed. RESULTS：The linear range of AP in plasma and tissue s were 0.1-25.0 μg/mL（all r＞0.99）；the lower limits of quantification were 0.1 μg/mL. RSDs of intra-day and inter-day were all lower than 15％，and the accuracy were 94.37％-117.48％. The extraction recovery rates were all more than 80％. Compared with AP solution group ，the concentrations of AP in plasma sample （during 0.5-6 h），liver tissue （during 0.25-8 h），spleen tissue （during 0.25-8 h）and cerebral tissue （during 0.25-4 h）were increased significantly in AP-NPs suspension group （P＜0.05 or P＜0.01），and the highest in liver tissue. The concentrations of AP in heart tiusse （6 h），liver tissue （10 h），lung tissue （0.5 h），spleen tissue （during 0.25-10 h）were decreased significantly （P＜ 0.05 or P＜0.01）. There was statistical significance in AUC and cmax of AP in plasma and tissue samples between 2 groups（P＜ 0.05）. The ce，RUE，uptake ratio and its change value of liver tissue were the highest ，being 1.34±0.40，1.99±0.29，48.49％ and 15.71％ . CONCLUSIONS ：After AP is made into nanosus- pension，the distribution of drug tissue is changed ，especially targeting effect on liver tissue is improved.
ABSTRACT
OBJECTIVE： To prepare Ursolic acid （UA）/Pluronic F127 （PF127）/TPGS-doxorubicin （DOX） mixed nanomicelles， and to characterize it and study its in vitro release behavior. METHODS： UA/PF127/TPGS nanomicelles were prepared by thin film hydration method. Using encapsulation efficiency of UA as index， combined with the results of single factor tests， L9（34） orthogonal test was used to optimize drug dosage of UA， molar ratio of PF127 to TPGS， hydration temperature and hydration volume， validation test was performed. On the basis of succinylated TPGS， TPGS-DOX was synthesized and mixed with UA/PF127/TPGS to prepare UA/PF127/TPGS-DOX mixed nanomicelles， the appearance， particle size and critical micelle concentration （PF127/TPGS） were investigated. The drug release behavior was examined by dialysis bag diffusion method. RESULTS： The optimal preparation technology of UA/PF127/TPGS nanomicelles was as follows as drug dosage of UA 8 mg， molar ratio of PF127 to TPGS 3 ∶ 7， hydration temperature 50 ℃， hydration volume 4 mL. Average encapsulation efficiency of UA in nanomicelles was 89.00％ （RSD＝0.43％， n＝3）. The prepared UA/PF127/TPGS-DOX mixed nanomicelles solution was clear with opalescence. The nanomicelles were spherical and uniform in size； average particle size was （115.00±9.42） nm； critical micelle concentration of PF127/TPGS （molecular ratio 3 ∶ 7） was 0.001 3％. The in vitro drug release of UA and DOX in the mixed nanomicelles was significantly slowed down， compared with raw materials or substance control. The drug release process of the two drugs in the nanomicelles conformed to Weibull equation. CONCLUSIONS： UA/PF127/TPGS-DOX mixed nanomicelles are successfully prepared with uniform particle size， good stability and good sustained-release effect.