Author/Editor     Prezelj, Marija; Neubauer, David; Derganc, Meta
Title     Measurement of purines in urine by capillary electrophoresis for estimating the degree of hypoxia in infants
Type     članek
Source     Clin Chem Lab Med
Vol. and No.     Letnik 38, št. 7
Publication year     2000
Volume     str. 623-8
Language     eng
Abstract     We describe a simple, rapid and reproducible method for measuring hypoxanthine, xanthine and uric acid in urine samples of infants by capillary electrophoresis with an uncoated fused silica capillary and ultraviolet detection. Conditions were 40 mmol/I borate buffer pH 9.4 with sodium dodecyl sulphate (0.1 mol) 3 s hydrodynamic load and the voltage 20 kV. The calibration curves for hypoxanthine and xanthine were linear to 150 Nmol/I and for uric acid to 300 Nmol/I. The limits of detection for hypoxanthine, xanthine and uric acid were 0.5, 2.0 and 20 Nmol/I, respectively. Analytical recovery of the three purines ranged from 93 to 105%. Overall CVs were <5.2%. Using this method, we measured purine concentrations in the urine samples of 103 infants, divided into three groups, according to different degrees of hypoxia. There was a significant difference among the three groups only in hypoxanthine concentrations. In 35 urine samples from the control group, 43 urine samples from infants with a history of an apparent life threatening episode and in 25 urine samples from infants with infantile apnoea, the mean concentrations of hypoxanthine (mean +- SD) were 13.1 +- 4.0, 25.1 +- 8.1 and 58.2 +- 17.4 micromol/mmol creatinine, respectively. The diagnostic accuracy of the purine measurement was evaluated by receiver-operating characteristic curve analysis.
Descriptors     PURINES
ELECTROPHORESIS, CAPILLARY
ANOXIA
INFANT
HYPOXANTHINE
XANTHINES
URIC ACID
LIFE SUPPORT CARE