TY - JOUR
T1 - Development and validation of a simple determination of urine metabolites (oxalate, citrate, uric acid and creatinine) by capillary zone electrophoresis
AU - Muñoz, Jose A.
AU - López-Mesas, Montserrat
AU - Valiente, Manuel
PY - 2010/4/15
Y1 - 2010/4/15
N2 - Oxalate, citrate, uric acid and creatinine are important urine markers for the evaluation and treatment of urolithiasic patients. They have been traditionally analysed by enzymatic and chromatographic techniques which present practical drawbacks, mainly in the sample pre-treatment step. The purpose of this study was to evaluate those markers in urine samples, by an easy multi-analyte assay using capillary zone electrophoresis. The four urine metabolites were determined, at 25 °C, by using a 50 cm × 75 μm capillary in 50 mmol l-1 phosphate buffer (pH 6.5), at constant voltage of -30 kV and UV detection at 195 nm (for oxalate and citrate) or 30 kV and 234 nm (for creatinine and uric acid). The sample pre-treatment was minimum, 5- and 20-fold dilution of the urine sample and acidification to pH 3-4. Validation parameters (linear range, sensitivity, accuracy, precision and detection limits) were statistically comparable to those obtained with the official methods normally used in the clinical practice. The effect of freezing as a conservation method of urine samples is also discussed in terms of recoveries of the analytes. The analytical method developed is highly useful as a diagnostic tool for detecting metabolic renal disorders due to its simplicity, time consuming, easy automation, cost efficiency and analytical effectiveness, accomplishing with the clinical requirements.
AB - Oxalate, citrate, uric acid and creatinine are important urine markers for the evaluation and treatment of urolithiasic patients. They have been traditionally analysed by enzymatic and chromatographic techniques which present practical drawbacks, mainly in the sample pre-treatment step. The purpose of this study was to evaluate those markers in urine samples, by an easy multi-analyte assay using capillary zone electrophoresis. The four urine metabolites were determined, at 25 °C, by using a 50 cm × 75 μm capillary in 50 mmol l-1 phosphate buffer (pH 6.5), at constant voltage of -30 kV and UV detection at 195 nm (for oxalate and citrate) or 30 kV and 234 nm (for creatinine and uric acid). The sample pre-treatment was minimum, 5- and 20-fold dilution of the urine sample and acidification to pH 3-4. Validation parameters (linear range, sensitivity, accuracy, precision and detection limits) were statistically comparable to those obtained with the official methods normally used in the clinical practice. The effect of freezing as a conservation method of urine samples is also discussed in terms of recoveries of the analytes. The analytical method developed is highly useful as a diagnostic tool for detecting metabolic renal disorders due to its simplicity, time consuming, easy automation, cost efficiency and analytical effectiveness, accomplishing with the clinical requirements.
KW - Capillary electrophoresis
KW - Citrate
KW - Creatinine
KW - Determination
KW - Oxalate
KW - Uric acid
UR - http://www.scopus.com/inward/record.url?scp=77049103061&partnerID=8YFLogxK
U2 - 10.1016/j.talanta.2009.12.014
DO - 10.1016/j.talanta.2009.12.014
M3 - Article
AN - SCOPUS:77049103061
SN - 0039-9140
VL - 81
SP - 392
EP - 397
JO - Talanta
JF - Talanta
IS - 1-2
ER -