Khan Sumsullah, Ahmad Ateeq, Guo Wei, Wang Yue-Fen, Abu-Qare Aqel, Ahmad Imran
Pharmacokinetics, Safety and Efficacy Department, Research and Development, NeoPharm, Inc., Waukegan, IL 60085, USA.
J Pharm Biomed Anal. 2005 Feb 7;37(1):135-42. doi: 10.1016/j.jpba.2004.09.053.
An LC/MS/MS method to quantify SN-38 in mouse plasma and tissue homogenates containing liposome entrapped SN-38 (LE-SN38) was developed. Camptothecin (CPT) was used as the internal standard (IS). Sample preparation consisted of simple protein precipitation by acetonitrile containing 0.5% acetic acid. SN-38 and IS were separated by a C18 HPLC column and detected using a mass spectrometer operating in the multiple reaction monitoring (MRM) mode. The peak area of the m/z 393.3-->349.1 transition of SN-38 and that of the m/z 349.1-->305.2 transition of the IS were measured and a standard curve was generated from their ratios. The method had a LLOQ of 0.5 ng/mL in mouse plasma, which corresponds to 2.5 pg for the 5 microL injection volume. The linear range was 0.5-1000 ng/mL of SN-38 in plasma sample spiked with LE-SN38. The LLOQ in tissue homogenates (5%, w/v) quantitation was 1 ng/mL (20 ng/g tissue) of SN-38 in kidney, liver, lung, and spleen homogenates, and 2 ng/mL (40 ng/g tissue) in heart homogenate containing LE-SN38. The assay was linear up to 400 ng/mL of SN-38 in tissue homogenates, and may be extended to 120 microg/mL by proper dilution of samples over the upper limit of quantitation. Acceptable precision and accuracy were obtained for concentrations over the entire standard curve range, both between-run and within-run for plasma and tissue homogenates. The method was successfully used to quantify SN-38 in plasma and tissues samples for pharmacokinetic and tissue distribution studies of LE-SN38 in mice.
建立了一种用于定量小鼠血浆和含有脂质体包裹的SN-38（LE-SN38）的组织匀浆中SN-38的液相色谱/串联质谱（LC/MS/MS）方法。喜树碱（CPT）用作内标（IS）。样品制备包括用含0.5%乙酸的乙腈进行简单的蛋白沉淀。SN-38和内标通过C18高效液相色谱柱分离，并使用在多反应监测（MRM）模式下运行的质谱仪进行检测。测量SN-38的m/z 393.3→349.1跃迁的峰面积和内标的m/z 349.1→305.2跃迁的峰面积，并根据它们的比值生成标准曲线。该方法在小鼠血浆中的最低定量限（LLOQ）为0.5 ng/mL，对于5 μL进样体积相当于2.5 pg。在加样了LE-SN38的血浆样品中，SN-38的线性范围为0.5 - 1000 ng/mL。在组织匀浆（5%，w/v）定量中，肾、肝、肺和脾匀浆中SN-38的LLOQ为1 ng/mL（20 ng/g组织），含LE-SN38的心脏匀浆中为2 ng/mL（40 ng/g组织）。在组织匀浆中，该测定法在高达400 ng/mL的SN-38浓度下呈线性，通过对超过定量上限的样品进行适当稀释，可扩展至120 μg/mL。对于血浆和组织匀浆，在整个标准曲线范围内的浓度，批间和批内均获得了可接受的精密度和准确度。该方法成功用于定量小鼠血浆和组织样品中的SN-38，以进行LE-SN38的药代动力学和组织分布研究。
