PK/PD and Toxicology Division, Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu 180001, India.
J Chromatogr B Analyt Technol Biomed Life Sci. 2010 Mar 15;878(9-10):823-30. doi: 10.1016/j.jchromb.2010.01.048. Epub 2010 Feb 6.
In the present investigation, a UPLC-qTOF-MS/MS method has been developed for the simultaneous determination of etoposide and a piperine analogue, namely, 4-ethyl 5-(3,4-methylenedioxyphenyl)-2E,4E-pentadienoic acid piperidide (PA-1). The analytes were separated on a reverse phase C18 column using methanol-water (72:28, v/v) mobile phase with a flow rate of 250 microL/min. The qTOF-MS was operated under multiple reaction monitoring mode using electro-spray ionization (ESI) technique with positive ion polarity. The major product ions for etoposide and PA-1 were at m/z 185.1350 and 164.1581, respectively. The recovery of the analytes from mouse plasma was optimized using solid phase extraction technique. The total run time was 6 min and the elution of etoposide and PA-1 occurred at 1.24 and 2.84 min, respectively. The calibration curves of etoposide as well as PA-1 were linear over the concentration range of 2-1000 ng/mL (r(2), 0.9829), and 1-1000 ng/mL (r(2), 0.9989), respectively. For etoposide intra-assay and inter-assay accuracy in terms of % bias was in between -7.65 to +6.26, and -7.83 to +5.99, respectively. For PA-1 intra-assay and inter-assay accuracy in terms of % bias was in between -7.01 to +9.10, and -7.36 to +6.71, respectively. The lower limit of quantitation for etoposide and PA-1 were 2.0 and 1.0 ng/mL, respectively. Analytes were stable under various conditions (in autosampler, during freeze-thaw, at room temperature, and under deep-freeze conditions). The method was used for a pharmacokinetic study which showed that PA-1 enhanced the oral bioavailability of etoposide in mice by 2.32-fold.
在本研究中，建立了一种同时测定依托泊苷和胡椒碱类似物（即 4-乙基-5-（3,4-亚甲二氧基苯基）-2E,4E-戊二烯酸哌啶）（PA-1）的 UPLC-qTOF-MS/MS 方法。分析物在反相 C18 柱上分离，采用甲醇-水（72:28，v/v）流动相，流速为 250μL/min。qTOF-MS 采用电喷雾电离（ESI）技术，正离子极性，在多重反应监测模式下运行。依托泊苷和 PA-1 的主要产物离子分别为 m/z 185.1350 和 164.1581。采用固相萃取技术优化了分析物从小鼠血浆中的回收率。总运行时间为 6 分钟，依托泊苷和 PA-1 的洗脱时间分别为 1.24 和 2.84 分钟。依托泊苷和 PA-1 的校准曲线在 2-1000ng/mL（r²，0.9829）和 1-1000ng/mL（r²，0.9989）范围内呈线性。依托泊苷的日内和日间准确度（%偏差）分别在-7.65 至+6.26 和-7.83 至+5.99 之间。PA-1 的日内和日间准确度（%偏差）分别在-7.01 至+9.10 和-7.36 至+6.71 之间。依托泊苷和 PA-1 的定量下限分别为 2.0 和 1.0ng/mL。分析物在各种条件下（在自动进样器中、冻融过程中、室温下和深冻条件下）均稳定。该方法用于药代动力学研究，结果表明 PA-1 使依托泊苷在小鼠体内的口服生物利用度提高了 2.32 倍。
