目的 拉洛他赛是国内外均未上市的新结构药物,未见质量研究相关报道。对拉洛他赛进行波谱解析以验证其分子式、相对分子质量和化学结构式,同时建立一种定量方法用于拉洛他赛脂质体制剂的含量测定。方法 利用质谱、红外吸收光谱、核磁共振波谱测定方法,对拉洛他赛进行药物结构和光谱学解析;利用紫外-可见分光光度法对拉洛他赛进行全波长扫描,确定其吸收波长;利用高效液相色谱法,建立拉洛他赛定量方法并用于脂质体拉洛他赛包封率的测定。结果 揭示了拉洛他赛的四大光谱学特征并制订相应的标准图谱。确认了拉洛他赛的结构为三环二萜,分子式为C₄₅H₅₃NO₁₄,相对分子质量为831.900 1。建立了拉洛他赛的高效液相色谱定量方法,其色谱柱为C18硅胶反相色谱柱 (5 μm, 250 mm×4.6 mm),流动相为乙腈-水(体积比75 ∶25),检测波长为230 nm,该方法可用于测定脂质体制剂中拉洛他赛的包封率,稳定性、回收率和精密度高。此外,新制备了拉洛他赛脂质体,该脂质体粒径大约105 nm,均一性良好,药物包封率大于80%。结论 制订了拉洛他赛的质谱、红外吸收光谱、核磁共振波谱和紫外-可见光谱图谱,验证了拉洛他赛的分子式、相对分子质量和结构式,建立了拉洛他赛的高效液相色谱定量方法,该方法可用于拉洛他赛脂质体的质量控制。

Objective: Larotaxel is a new chemical structure drug, which has not been marketed worldwide. Accordingly, the standard identification and quantification methods for larotaxel remain unclear. The spectrometric analyses were performed for verifying weight molecular formula, molecular weight and chemical structure of larotaxel. Besides, a quantification method was developed for measuring larotaxel in the liposomes.Methods: The molecular formula, molecular weight and chemical structure of larotaxel were studied by using mass spectrometry (MS), infra-red (IR), nuclear magnetic resonance (NMR) and ultraviolet-visible (UV-vis) spectrometric techniques. The absorption wavelength of larotaxel was investigated by UV-vis spectrophotometry full-wavelength scanning. Besides, a quantification method was developed by high performance liquid chromatography (HPLC), and then validated by measuring the encapsulation efficacy of larotaxel liposomes. Results: The four spectral characteristics of larotaxel were revealed and the corresponding standard spectra were defined. It was confirmed that larotaxel had the structure of tricyclic diterpenoids, with the molecular formula of C₄₅H₅₃NO₁₄, the molecular weight of 831.900 1, and the maximum absorption wavelength of 230 nm. The quantitative method of larotaxel was established by using HPLC with a reversed phase C18 column (5 μm, 250 mm×4.6 mm), a mobile phase of acetonitrile-water (75 ∶25, volume/volume), and a detection wavelength of 230 nm. The validation study exhibited that the established HPLC method was stable, and had a high recovery and precision in the quantitative measurement of larotaxel in liposomes. In addition, a new kind of larotaxel liposomes was also successfully prepared. The particle size of the liposomes was about 105 nm, with an even size distribution. And the encapsulation efficiency of larotaxel in the liposomes was above 80%.Conclusion: The present study offers reference standard spectra of larotaxel, including MS, IR, NMR, and UV-vis, and confirms the molecular formula, molecular weight and chemical structure of larotaxel. Besides, the study develops a rapid HPLC method for quality control of larotaxel liposomes.