Lanz Christian, Früh Martin, Thormann Wolfgang, Cerny Thomas, Lauterburg Bernhard H
Departement für Innere Medizin, Fachbereich Onkologie/Hämatologie, Kantonsspital St. Gallen, Switzerland.
J Sep Sci. 2007 Aug;30(12):1811-20. doi: 10.1002/jssc.200600534.
Gemcitabine (2'2'-difluorodeoxycytidine) is a pyrimidine analog used in the treatment of a variety of solid tumors. After intravenous (i.v.) administration, it is rapidly inactivated to 2'-deoxy-2',2'-difluorouridine (dFdU). A sensitive analytical method for the quantitation of gemcitabine is required for the assessment of alternative dosage and treatment schemes. A rapid and robust RP-HPLC assay for analysis of gemcitabine in human and animal plasma and serum was developed and validated using 2'-deoxyuridine (dU) and 5-fluoro-2'-deoxyuridine (5FdU) as internal standards. It is based on protein precipitation, the use of an Atlantis dC18 column of 100 mm length (inner diameter, 4.6 mm; particle size, 3 microm) and isocratic elution using a 10 mM phosphate buffer, pH 3.0, followed by isocratic elution with the same buffer containing 3% of ACN. For gemcitabine, RSD values for intraday and interday precision were < 4.4 and 5.3%, respectively, the LOQ was 20 ng/mL, and the assay was linear in the range of 0.020-20 microg/mL with an accuracy of > or =89%. The recovery for gemcitabine, dU and 5FdU was 86-98%. The assay was applied to determine gemcitabine levels in plasma samples of patients collected during and shortly after conventional infusion of 25-30 mg/kg body mass (levels: 2.0-18.9 microg/mL) and rats that received lower doses (1.5 mg/kg) via i.v., subcutaneous and oral drug administration (levels: 0.20-2.60 microg/mL). It could also be applied to estimate dFdU levels in human plasma.
吉西他滨（2'2'-二氟脱氧胞苷）是一种用于治疗多种实体瘤的嘧啶类似物。静脉注射后，它会迅速失活为2'-脱氧-2',2'-二氟尿苷（dFdU）。为了评估替代剂量和治疗方案，需要一种灵敏的分析方法来定量吉西他滨。采用2'-脱氧尿苷（dU）和5-氟-2'-脱氧尿苷（5FdU）作为内标，开发并验证了一种快速、稳健的反相高效液相色谱法（RP-HPLC），用于分析人和动物血浆及血清中的吉西他滨。该方法基于蛋白质沉淀，使用100 mm长（内径4.6 mm；粒径3微米）的Atlantis dC18柱，先用10 mM pH 3.0的磷酸盐缓冲液等度洗脱，然后用含3%乙腈的相同缓冲液等度洗脱。对于吉西他滨，日内和日间精密度的相对标准偏差（RSD）值分别<4.4%和5.3%，定量限（LOQ）为20 ng/mL，该方法在0.020 - 20 μg/mL范围内呈线性，准确度≥89%。吉西他滨、dU和5FdU的回收率为86 - 98%。该方法用于测定常规输注25 - 30 mg/kg体重期间及之后不久收集的患者血浆样本中的吉西他滨水平（水平：2.0 - 18.9 μg/mL），以及通过静脉注射、皮下注射和口服给药接受较低剂量（1.5 mg/kg）的大鼠血浆中的吉西他滨水平（水平：0.20 - 2.60 μg/mL）。它还可用于估计人血浆中的dFdU水平。
