| To the development of new drug, the quality research and quality standardsformulation are the main content of drug development. The quality should be reserchedin depth and systematically in process of drug development, the quality standards shouldbe scientific, reasonable and feasible, but that is not enough, it is necessary to continue toamend and revise, the purpose and significance is to ensure that the drug is safe, efficientand controllable. At the same time, long-circulation thermosensitive liposomes whichquality research is significantly different from the other dosage form as its specificity andcomplexty, but there is no uniform rules about it so far. The subject is to study on thequality of long-circulation thermosensitive liposomes containing docetaxel(DLTL)andprovide some certain reference value for this special dosage form.Firstly, this study has established an HPLC method for determination of content andrelated substances of docetaxel. After referenced to some literature and date, the analysisfor determination of content was performed on a C18column(150mm×4.6mm,5μm),using a mobile phase of acetonitrile-distilled water(55/45) at the flow rate of1.0mL/min.Referencing to the quality standards of docetaxel injection in USP34, the analysis fordetermination of related substances was performed on a C18column(150mm×4.6mm,5μm), the mobile phase was composed of acetonitrile and distilled water with a gradientelution at flow rate of1.2mL/min. The detection wavelength was230nm and the columntemperature was45℃. At the same time, the study researched the various stages ofprocess and the process conditions which impact on related substances. Secondly,Centrifugation was applied to isolate free drug and high performance liquidchromatography was used to determine the entrapment efficiency of DLTL. Investigatedthe separation of DLTL and free drug at different rotation speed, the best separationconditions was determined. Finally, the stability test of the DLTL has also beeninvestigated and formulated the quality draft standard. Stability test composed of two aspect as follows, the first one was dilution stability investigation in vitro, the second onewas storage stability investigation.5%glucose solution was used to diluted DLTL anddetected the samples at different time point. The detecting index was mainly particlesize,content, entrapment efficiency and leakage rate. To get the influencing factors,possible degradation pathways, degradation products and storage conditions, referencingto Chemical drug stability guiding principles, the test of storage stability was composedof impacting factor test and the long stability test.Under the optimal chromatographic condition, the related substances, blankliposome, solution and docetaxel could be completely separated. The calibration curveswere linear between1.0μg/mL~200.0μg/mL(r=0.9999). The average recovery was100.59%(RSD=0.62, n=9). The entrapment efficiency of DLTL was determined,followed by low-speed centrifugation at9300×g for10min. The average recovery was101.36%(RSD=059%, n=9). The test of dilution stability in vitro shows that DLTL wasdiluted with5%glucose solution could be valid for48h at room temperature. Influencingfactor test shows that DLTL was sensitive to temperature and light, it should be sealed atdark place in-20℃. The result of long-term test shows that DLTL could be valid for twomonths at dark place in-20℃.The method of HPLC for determination of content and related substances ofdocetaxel was accurate, sensitive and applicable for quality control of DLTL. Themethod of centrifugation could be applied in the determination of the entrapmentefficiency of DLTL and it is simple and accurate. The result of stability study shows thatDLTL could be valid for two months at-20℃. |
PDF Full Text Request