Is pre‐heat necessary for the measurement of 8‐oxo‐7, 8‐dihydroguanosine and 8‐oxo‐7, 8‐dihydro‐2′‐deoxyguanosine in urine samples. Issue 10 (29th August 2022)

• Record Type: Journal Article
• Authors: Zou, Yutong; Ma, Xiaoli; Yu, Songlin; Qiu, Ling
• Is Part Of: Journal of clinical laboratory analysis. Volume 36:Issue 10(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-29
• Subjects: 8‐oxo‐7, 8‐dihydro‐2′‐deoxyguanosine -- 8‐oxo‐7, 8‐dihydroguanosine -- LC–MS/MS -- pre‐heat; Diagnosis, Laboratory -- Periodicals; Medical laboratory technology -- Periodicals; 616
• DOI: 10.1002/jcla.24674
• Languages: English
• ISSNs: 0887-8013

Abstract

Abstract: Background: It is currently unclear for the necessary of pre‐heating urine samples for the accurate determination of 8‐oxo‐7, 8‐dihydroguanosine (8‐oxoG) and 8‐oxo‐7, 8‐dihydro‐2′‐deoxyguanosine (8‐oxodG). Thus, we conducted this study to evaluate the effect of pre‐heat (i.e., to 37°C) on the accurate measurement of 8‐oxoG and 8‐oxodG in frozen urine samples. Methods: Random urine samples from six healthy volunteers, six patients with renal dysfunction, and six patients with systematic diseases such as diabetes were collected, split, and stored at −80°C for up to 1 month. The frozen samples were thawed at room temperature (RT) or 37°C for different time, 10‐fold diluted with ddH2O containing 1% formic acid, and determined by self‐established LC–MS/MS method coupled with an ACQUITY™ Primer HSS T3 column. Results: Thawing the samples at RT for 30 or 120 min, or at 37°C for 15 or 90 min did not affect the determination of 8‐oxoG and 8‐oxodG in urine samples. Moreover, no significant difference between thawing the urine samples at RT and 37°C was found after storing at −80°C for 1–3 months. Conclusion: It is not always necessary to pre‐heat the frozen urine samples to release 8‐oxoG and 8‐oxodG from precipitates, which is associated with different pre‐treatment and determination methods. Abstract : For both apparently healthy volunteers and patients with kidney dysfunction or other systematic diseases, no significant difference between thawing the frozen urine samples at RT and 37°C was found for the accurate determinations of urinary 8‐oxoG and 8‐oxodG with this pre‐treatment and determination method.