胶束电动毛细管色谱法分离左旋十八甲基炔诺酮、睾酮和孕酮

胶束电动毛细管色谱法（MECC）被用于左施十八甲基炔诺酮（LNC）、睾酮（T）和孕酮（P）的分离。电泳缓冲液中含一定量的乙腈或甲醇等有机添加剂时,可以改善分离。当乙睛体积分数为0～15％时,样品的迁移时间tm随着乙腈体积分数的增加而增加,但当已腈体积分数大于15％时,样品的tm随乙腈体积分数的增加反而减少。如采用20mmol／L的2,6-二甲基-β-环糊精（DM-β-CD）作添加剂,不仅可提高分高度,而且能缩短分析时间,实现最佳分离。     

Monitoring of progestins: Development of immunochemical methods for purification and detection of levonorgestrel

A polyclonal antibody (Ab) for the progestin levonorgestrel (LNG) was generated, and immunochemical assays for its detection, clean-up and concentration were developed. A highly specific microplate diagnostic assay for the detection of LNG was developed that used the enzyme linked immunosorbent assay (ELISA) method. The LNG ELISA developed was sensitive and reproducible; it exhibited I₅₀ and I₂₀ values of 3.3 ± 1.8 ng mL⁻¹ and 0.6 ± 0.4 ng mL⁻¹, respectively, and the Abs did not cross react with any of the tested steroid hormones. The above Abs were used to develop a sol-gel-based immunoaffinity purification (IAP) method for concentration and clean-up of LNG that is compatible with subsequent immunochemical or instrumental chemical analytical procedures, such as liquid chromatography followed by mass spectrometry (LC-MS/MS). Development of the columns included successful entrapment of Abs within a tetramethoxysilane (TMOS)-based SiO₂ polymer network. The Abs could bind the free analyte from solution, and the bound analyte could be easily eluted from the sol-gel matrix at high recoveries. The Ab selectivity towards the antigen was high, in both ELISA and the sol-gel columns, but the entrapped Abs cross-reacted with two other steroid hormones - ethynylestradiol (EE2) and nortestosterone (NT) - which share similar epitopes with LNG, despite the lack of cross reactivity in the ELISA. The validity of the method was investigated by LC-MS/MS and a good analytical correlation was obtained.     

间接酶联免疫吸附分析法对环境水样中左旋18-甲基炔诺酮含量的测定

本文报道测定环境水样中的左旋18-甲基炔诺酮(NG)的间接酶联免疫吸附分析法(ELISA)。通过对左旋18-甲基炔诺酮的化学修饰,将左旋18-甲基炔诺酮与蛋白质载体结合,制成完全免疫抗原,经过多次动物免疫得到了兔抗左旋18-甲基炔诺酮抗体,在优化实验条件的基础上,建立了灵敏度高、特异性强、简便、稳定的测定水样中左旋18-甲基炔诺酮的酶联免疫吸附分析方法。IC50值(标准曲线中吸光度抑制至最大吸光度值的50%时所对应的待测物浓度)在1μg/L~5μg/L,最低检出限为0.05μg/L~0.1μg/L。水样的加标回收率在88%~140%之间。真实环境水样中,均发现含有左旋18-甲基炔诺酮,浓度在0.3μg/L-0.6μg/L之间。     

液相色谱-电喷雾串联质谱法快速测定人体血液中左旋甲基炔诺酮的含量

建立了快速测定人体血液中左旋甲基炔诺酮的液相色谱-串联质谱法.样品加入内标后,经过一个简单的预处理,以电喷雾正离子多反应监测方式进行定性定量分析,并且优化了液相和质谱条件.方法简单快速,一个样品的分析时间仅需10min;方法的检出限为0.2 ng/mL,线性范围为0.625ng/mL~35.0ng/mL,测定结果重复性很好,日内和日间的相对标准偏差均小于3.74%,在添加浓度为1.25ng/mL、5.0ng/mL3、5.0 ng/mL时,回收率分别为(92.1±2.8)%,(95.7±3.4)%,(105.8±3.1)%.通过以与新鲜血液比较,经过冷冻~解冻后的血液样品测量值稳定.结果表明,本方法适合于人体血清中左旋甲基炔诺酮含量的测定.     

Simultaneous determination of four hormonal compounds in oral contraceptive tablet formulations by high performance liquid chromatography

A rapid, accurate, and precise HPLC method has been developed for simultaneous determination of four contraceptive hormonal compounds namely ethinylestradiol (EE), drospirenone (DR), gestodene (GS), and levonorgestrel (LV) in oral contraceptive tablet dosage form. The chromatographic separation was achieved on a C18 (150 × 4.6 mm, 5μ) column; the mobile phase consists of acetonitrile: water (50:50, v/v) pumped at a flow rate of 1.0 mL/min; and UV detection was set at 200 nm. The limit of detection was 0.0086 µg/mL for (EE), 0.0397 µg/mL for (GS), 2.80 µg/mL for (DR), and 0.229 µg/mL for (LV), whereas the limit of quantitation (LOQ) was 0.028 µg/mL for (EE), 0.132 µg/mL for (GS), 9.500 µg/mL for (DR), and 0763 µg/mL for (LV), respectively. The correlation coefficient (r) values of the four compounds ranged from 0.99995 to 0.99999. The method was validated as per ICH guidelines and USP 34 for estimation of (EE), (DR), (GS), and (LV) in commercially available tablet dosage form. The validation results were found satisfactory. The proposed method can be useful in quality control of bulk manufacturing and pharmaceutical dosage forms.     

Development of a broad selective molecularly imprinted polymers-based solid phase extraction of contraceptive drug levonorgestrel from water samples

A broad selective molecularly imprinted polymers-based solid phase extraction (MISPE) for levonorgestrel (LNG) from water samples was developed. Using LNG as a template molecule, acrylamide (AA) as functional monomer, ethylene glycol dimethacrylate (EGDMA) as linking agent and bulk polymerisation as a synthetic method, the molecularly imprinted polymers (MIPs) were synthesised and characterised. The MIPs displayed a high specific rebinding for LNG with the imprinting factor of 3.71. The Scatchard analysis showed that there was at least one class of binding site for LNG formed in the MIPs with the dissociation constant of 8.046?µg?mL^?1. The results of selectivity testing indicated that the MIPs also exhibited high cross-reactivity with structurally related compounds (estrone, methylprednisolone and ethinyl estradiol), but no recognition with non-structurally related compound (indomethacin), suggesting that the MIPs could be used as a broad recognition absorbent. MISPE column was prepared by packing MIPs particles into a common SPE cartridge. The MISPE extraction conditions including loading, washing and eluting solutions were carefully optimised. Water samples spiked with LNG were extracted by MISPE column and detected by high-performance liquid chromatography. The recoveries were found to be 79.97?～?132.79% with relative standard deviations (RSD) of 1.92?～?10.43%, indicating the feasibility of the prepared MIPs for LNG extraction.     

Levonorgestrel Microneedle Array Patch for Sustained Release Contraception: Formulation,Optimization and In Vivo Characterization

Background: The goal of this work was to develop a levonorgestrel liposome-loaded microneedle array patch for contraception. Methods: Levonorgestrel-loaded liposome was formulated by a solvent injection technique, characterized, and studied. Results: The formulated liposomes were characterized for particle size (147 ± 8 nm), polydispersity index (0.207 ± 0.03), zeta potential (−23 ± 4.25 mV), drug loading (18 ± 3.22%) and entrapment efficiency (85 ± 4.34%). A cryo high-resolution transmission electron microscopy and cryo field emission gun scanning electron microscopy study showed spherical shaped particles with a smooth surface. The in vitro drug release and in vivo pharmacokinetic study showed sustained behaviour of Levonorgestrel for 28 days. Conclusion: The levonorgestrel liposome-loaded microneedle array patch showed better contraception than the drug-loaded microneedle array patch.     

6-亚甲基-17α-乙酰氧基-18-甲基-19-失碳-孕甾-4-烯-3,20-二酮的合成新方法研究

报道了16-亚甲基-17α-乙酰氧基-18-甲基-19-失碳-孕甾-4-烯-3,20-二酮的新合成方法. 以左旋18-甲基炔诺酮为原料, 通过脱水、氧化、环合、热解、环氧化、开环氧环、水解七步反应合成了目标化合物, 总收率20.0%. 其中化合物12, 13, 14, 15, 16尚未见文献报道.     

~3H-左旋18-甲基炔诺酮的合成

采用化学合成法制备了不饱和有机化合物~3H-左旋18-甲基炔诺酮,确保了分子中的炔基不被氢化.放射性比度为15.54GBq/mmol,放化纯度为95.7％.产品经热实验证实热稳定性良好,且在37℃生理盐水(pH=6.5)中氢-氚交换速率较低.     

Determination of levonorgestrel in human plasma by liquid chromatography-tandem mass spectrometry method: application to a bioequivalence study of two formulations in healthy volunteers

A rapid and sensitive liquid chromatography-tandem mass spectrometry (LC/MS/MS) method to determine levonorgestrel in human plasma was developed and fully validated. After hexane-ethyl acetate (70:30, v/v) induced extraction from the plasma samples, levonorgestrel was subjected to LC/MS/MS analysis using electro-spray ionization. The MS system was operated in the selected reaction monitoring mode. Chromatographic separation was performed on a Hypersil BDS C18 column (i.d. 2.1x50 mm, particle size 3 microm). The method had a chromatographic running time of 2.0 min and linear calibration curves over the concentration ranges of 0.25-90 ng/mL for levonorgestrel. The lower limit of quantification of the method was 0.25 ng/mL for levonorgestrel. The intra- and inter-batch precision was 3.7-10.2 and 5.1-12.9%, respectively, for all quality control samples at concentrations of 0.5, 6.0 and 45.0 ng/mL. These results indicate that the method was efficient with a simple preparation procedure and a very short running time (2.0 min) for levonorgestrel compared with those methods reported in the literature and had high selectivity, acceptable accuracy, precision and sensitivity. The validated LC/MS/MS method was successfully used for a bioequivalence study of two tablet formulations of levonorgestrel in healthy volunteers.