Determination of GTI-2040, a novel antisense oligonucleotide, in human plasma by using HPLC combined with solid phase and liquid–liquid extractions

• Published in: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Vol. 829; no. 1; pp. 45 - 49
• Main Authors: Zhang, Wenjiang, Leighl, Natasha, Zawisza, Diane, Moore, Malcolm J., Chen, Eric X.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 27.12.2005; Elsevier Science
• Subjects: Analysis; Analytical, structural and metabolic biochemistry; Antisense oligonucleotide; Biological and medical sciences; Chromatography, High Pressure Liquid - methods; Fundamental and applied biological sciences. Psychology; General pharmacology; GTI-2040; Humans; Medical sciences; Oligodeoxyribonucleotides; Oligonucleotides, Antisense - blood; Oligonucleotides, Antisense - pharmacokinetics; Pharmacology. Drug treatments; Sensitivity and Specificity; Solid-phase extraction; Spectrophotometry, Ultraviolet; Antisense oligonucleotide; GTI-2040; Solid-phase extraction; Human; Solid phase extraction; Biological fluid; Enzyme; Liquid liquid extraction; Transferases; Glycosyltransferases; HPLC chromatography; Blood plasma; Hexosyltransferases; Flavonol 3-O-glucosyltransferase; Quantitative analysis
• ISSN: 1570-0232; 1873-376X
• DOI: 10.1016/j.jchromb.2005.09.036

GTI-2040 is a 20-mer phosphorothioate oligonucleotide complementary to the mRNA of the R2 subunit of ribonucleotide reductase (RNR). It is under clinical development as an anti-cancer agent. A reverse phase high-performance liquid chromatograph (HPLC) method was established for the quantitative analysis of GTI-2040 in human plasma. Plasma samples were prepared with an initial solid-phase extraction (SPE) followed by a liquid–liquid extraction step. HPLC analysis was performed with a gradient system on a Waters XTerra ®MS C18 column. The mobile phase consisted of acetonitrile–tetrabutyl ammonium hydrogen sulfate (TBAS) buffer (pH 9.0, 20 mM) at a flow rate of 1.0 ml/min, and the detector was set at a wavelength of 260 nm. A cationic pairing reagent, tetrabutyl ammonium hydrogen sulfate was added during plasma sample clean-up with solid-phase extraction, resulting in significant improvement in extraction recovery. In addition, TBAS addition to the mobile phase improved the peak symmetry of GTI-2040. This method was successfully used in the analysis of GTI-2040 in clinical plasma samples.