title: Simultaneous determination of irinotecan (CPT-11) and SN-38 in tissue culture media and cancer cells by high performance liquid chromatography: application to cellular metabolism and accumulation studies.
abstract: A simple and sensitive HPLC method was developed to simultaneously determine CPT-11 and its major metabolite SN-38 in culture media and cell lysates. Camptothecin (CPT) was used as internal standard (I.S.). Compounds were eluted with acetonitrile-50 mM disodium hydrogen phosphate buffer containing 10 mM sodium 1-heptane-sulfonate, with the pH adjusted to 3.0 using 85% (w/v) orthophosphoric acid (27/73, v/v) by a Hyperclon ODS (C18) column (200 mm x 4.6 mm i.d.), with detection at excitation and emission wavelengths of 380 and 540 nm, respectively. The average extraction efficiencies were 96.9-108.3% for CPT-11 in culture media and 94.3-107.2% for CPT-11 in cell lysates; and 87.7-106.8% for SN-38 in culture media and 90.1-105.6% for SN-38 in cell lysates. Within- and between-day precision and accuracy varied from 0.1 to 10.3%. The limit of quantitation (precision and accuracy <20%) was 5.0 and 2.0 ng/ml for CPT-11 and 1.0 and 0.5 ng/ml for SN-38 in culture media and cell lysates, respectively. This method was successfully applied to quantitate the cellular accumulation and metabolism of CPT-11 and SN-38 in H4-II-E, a rat hepatoma cell line.
authors.affiliation: Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore 117543, Singapore.
authors.forename: Ze-Ping
authors.initials: ZP
authors.lastname: Hu
authors.forename: Xiao-Xia
authors.initials: XX
authors.lastname: Yang
authors.forename: Xiao
authors.initials: X
authors.lastname: Chen
authors.forename: Eli
authors.initials: E
authors.lastname: Chan
authors.forename: Wei
authors.initials: W
authors.lastname: Duan
authors.forename: Shu-Feng
authors.initials: SF
authors.lastname: Zhou
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000378:metabolism*; D002166:Camptothecin / Q000031:analogs & derivatives* / Q000378:metabolism; D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003470:Culture Media; D000077146:Irinotecan; D051381:Rats; D013050:Spectrometry, Fluorescence
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D003470:Culture Media; D000077146:Irinotecan; D002166:Camptothecin