Inter-laboratory Validation of Procedures for Measuring 8-oxo-7,8-dihydroguanine/8-oxo-7,8-dihydro-2′-deoxyguanosine in DNA

• Published in: Free radical research Vol. 36; no. 3; pp. 239 - 245
• Main Authors: Collins, Andrew R., Gedik, Catherine, Wood, Sharon, White, Ann, Dubois, Jacques, Duez, Pierre, Rees, Jean-François, Legall, Rozenn, Degand, Liliane, Loft, Steffen, Jensen, Annie, Poulsen, Henrik, Weimann, Allan, Jensen, Bente Riis, Cadet, Jean, Douki, Thierry, Ravanat, Jean-Luc, Faure, Henry, Tripier, Michèle, Morel, Isabelle, Sergent, Odile, Cillard, Pierre, Morin, Bénédicte, Epe, Bernd, Phoa, Nicole, Hartwig, Andrea, Pelzer, Anke, Dolara, Piero, Casalini, Chiara, Guglielmi, Francesco, Luceri, Cristina, Kasai, Hiroshi, Kido, Rie, Olinski, Ryszard, Bialkowski, Karol, Dura ková, Zdena, Hlin iková, Lucia, Korytar, Peter, Dušinská, Mária, Mislanová, Csilla, Viña, José, Lloret, Ana, Möller, Lennart, Hofer, Tim, Gremaud, Eric, Fay, Laurent, Stadler, Richard, Eakins, Julie, Pognan, François, O'Brien, John, Elliott, Ruan, Astley, Siân, Bailley, Angela, Herbert, Karl, Chauhan, Dina, Kelly, Frank, Dunster, Chrisi, Lunec, Joseph, Podmore, Ian, Patel, Parul, Johnson, Samantha, Evans, Mark, White, Andrea, Tyrrell, Rex, Gordon, Matthew, Wild, Chris, Hardie, Laura, Smith, Elizabeth
• Format: Journal Article
• Language: English
• Published: England Informa UK Ltd 01.03.2002; Taylor & Francis
• Subjects: 8-Oxodexyguanosine (8-oxo-dG); Animals; Biomarkers - analysis; Cattle; Chromatography, High Pressure Liquid; Chromatography, Liquid; DNA - chemistry; DNA Damage; Gas Chromatography-Mass Spectrometry; Guanine - analogs & derivatives; Guanine - analysis; Humans; Mass Spectrometry; Medicin och hälsovetenskap; Methods Validation; Oxidative Dna Damage; Photosensitiser; Sensitivity and Specificity; Thymus Gland - chemistry
• ISSN: 1071-5762; 1029-2470
• DOI: 10.1080/10715760290019246

The aim of ESCODD, a European Commission funded Concerted Action, is to improve the precision and accuracy of methods for measuring 8-oxo-7,8-dihydroguanine (8-oxoGua) or the nucleoside (8-oxodG). On two occasions, participating laboratories received samples of different concentrations of 8-oxodG for analysis. About half the results returned (for 8-oxodG) were within 20% of the median values. Coefficients of variation (for three identical samples) were commonly around 10%. A sample of calf thymus DNA was sent, dry, to all laboratories. Analysis of 8-oxoGua/8-oxodG in this sample was a test of hydrolysis methods. Almost half the reported results were within 20% of the median value, and half obtained a CV of less than 10%. In order to test sensitivity, as well as precision, DNA was treated with photosensitiser and light to introduce increasing amounts of 8-oxoGua and samples were sent to members. Median values calculated from all returned results were 45.6 (untreated), 53.9, 60.4 and 65.6 8-oxoGua/10 6 Gua; only seven laboratories detected the increase over the whole range, while all but one detected a dose response over two concentration intervals. Results in this trial reflect a continuing improvement in precision and accuracy. The next challenge will be the analysis of 8-oxodG in DNA isolated from cells or tissue, where the concentration is much lower than in calf thymus DNA.