{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T13:06:41Z","timestamp":1787317601687,"version":"build-2736575974"},"reference-count":34,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,5,13]],"date-time":"2021-05-13T00:00:00Z","timestamp":1620864000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>High performance liquid chromatography with ultra-violet detection (HPLC-UV) and gas chromatography\u2013mass spectrometry (GC-MS) methods were developed and validated for the determination of chlorambucil (CLB) and valproic acid (VPA) in plasma, as a part of experiments on their anticancer activity in chronic lymphocytic leukemia (CLL). CLB was extracted from 250 \u00b5L of plasma with methanol, using simple protein precipitation and filtration. Chromatography was carried out on a LiChrospher 100 RP-18 end-capped column using a mobile phase consisting of acetonitrile, water and formic acid, and detection at 258 nm. The lowest limit of detection LLOQ was found to be 0.075 \u03bcg\/mL, showing sufficient sensitivity in relation to therapeutic concentrations of CLB in plasma. The accuracy was from 94.13% to 101.12%, while the intra- and inter-batch precision was \u22649.46%. For quantitation of VPA, a sensitive GC-MS method was developed involving simple pre-column esterification with methanol and extraction with hexane. Chromatography was achieved on an HP-5MSUI column and monitored by MS with an electron impact ionization and selective ion monitoring mode. Using 250 \u00b5L of plasma, the LLOQ was found to be 0.075 \u03bcg\/mL. The accuracy was from 94.96% to 109.12%, while the intra- and inter-batch precision was \u22646.69%. Thus, both methods fulfilled the requirements of FDA guidelines for the determination of drugs in biological materials.<\/jats:p>","DOI":"10.3390\/molecules26102903","type":"journal-article","created":{"date-parts":[[2021,5,14]],"date-time":"2021-05-14T03:28:36Z","timestamp":1620962916000},"page":"2903","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["HPLC-UV and GC-MS Methods for Determination of Chlorambucil and Valproic Acid in Plasma for Further Exploring a New Combined Therapy of Chronic Lymphocytic Leukemia"],"prefix":"10.3390","volume":"26","author":[{"given":"Katarzyna","family":"Lipska","sequence":"first","affiliation":[{"name":"Department of Medicinal Chemistry, Medical University of Lublin, 20-090 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2503-5272","authenticated-orcid":false,"given":"Anna","family":"Gumieniczek","sequence":"additional","affiliation":[{"name":"Department of Medicinal Chemistry, Medical University of Lublin, 20-090 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4566-6941","authenticated-orcid":false,"given":"Rafa\u0142","family":"Pietra\u015b","sequence":"additional","affiliation":[{"name":"Department of Medicinal Chemistry, Medical University of Lublin, 20-090 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7591-5887","authenticated-orcid":false,"given":"Agata A.","family":"Filip","sequence":"additional","affiliation":[{"name":"Department of Cancer Genetics with Cytogenetics Laboratory, Medical University of Lublin, 20-080 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1002\/cjoc.201500908","article-title":"Improvement of stability and anticancer activity of chlorambucil-tetrapeptide conjugate vesicles","volume":"34","author":"Zhang","year":"2016","journal-title":"Chin. 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