▎ 摘　　要

NOVELTY - Solid-phase extraction of modified nucleosides in urine involves using graphene material as a solid-phase extraction column filler, extracting and enriching several modified nucleosides in urine, detecting and analyzing using liquid chromatography tandem mass spectrum. The detection sensitivity and accuracy are improved. The detection method involves unfreezing a urine sample at room temperature, centrifuging, taking supernatant, adding an isotope internal standard solution, adding water for dilution, weighing 0.1-1 mg adsorbent filler in a solid phase extraction column, activating and balancing with methanol and water, adding the diluted urine sample into a solid phase extraction column, washing, drying, eluting, collecting eluent, vacuum centrifugal drying, re-dissolving with water, analyzing and detecting using a liquid chromatography tandem mass spectrometry. USE - Solid-phase extraction of modified nucleosides e.g. N6-methyladenosine, N1-methyladenosine, 2'-O-methyladenosine, N6, 2 '-O-dimethyladenosine, 2'-O-methylguanosine, N1-methylguanosine, N2-methylguanosine, N7-methylguanosine, N2, N2-dimethylguanosine, 2'-O-methyluridine, 3-methyluridine, 5-methyluridine, 5, 2'-O-dimethyluridine, 2'-O-methylcytidine, 3-methylcytidine, 5-methylcytidine and N4-acetylcytidine in urine (all claimed), and used for analytical chemistry, metabonomics, clinical medicine and preventive medicine applications. ADVANTAGE - The method ensures extraction of modified nucleosides e.g. N6-methyladenosine (m6A), N1-methylguanosine (m1G), 5-methyluridine (m5U) and 5-methylcytidine (m5C) biological samples such as urine. DETAILED DESCRIPTION - Solid-phase extraction of modified nucleosides in urine involves using graphene material as a solid-phase extraction column filler, extracting and enriching several modified nucleosides in urine, detecting and analyzing using liquid chromatography tandem mass spectrum. The detection sensitivity and accuracy are improved. The detection method involves unfreezing a urine sample at room temperature, centrifuging at 13000 rpm at 4℃ for 15 minutes, taking supernatant into 1.5 mL centrifuge tube, adding an isotope internal standard solution, adding water for dilution, weighing 0.1-1 mg adsorbent filler in a solid phase extraction column, sequentially activating and balancing with methanol and water, adding the diluted urine sample into a solid phase extraction column, washing with water, drying by a vacuum pump, eluting, collecting eluent, vacuum centrifugal drying the eluent, re-dissolving with water, analyzing and detecting mixed standard solutions with different concentrations by using a liquid chromatography tandem mass spectrometry, obtaining a linear regression equation by using a peak area ratio of a standard substance and an isotope internal standard corresponding to the standard substance, measuring a urine sample, and substituting the linear equation to calculate the content of an analyte in the sample.