Simultaneous detection of paraquat and creatinine in urine by capillary electrophoresis

Abstract

Objective To establish a method for detecting the concentration of paraquat (PQ) and creatinine (Cr) in urine simultaneously by capillary electrophoresis. Methods Experimental methodological study.8 acute PQ poisoned patients who were treated in the First People′s Hospital of Lianyungang from January 2011 to June 2012 were collected.2 were male,and 6 were female.The separation were carried out using a 25 mmol/L pH 1.97 glycine-HCl buffer (containing 40 mmol/L NaCl) in a fused-sillica capillary tube of 47 cm×75μm I.D.by capillary zone electrophoresis.Urine had been injected by pressure for 4 s after samples were centrifuged and diluted for 10 times with H2O.The detection were monitored by a diode-array detector at 200 nm while samples were separated at a voltage of 20 k V.A systemic methodological evaluation of this method was carried out (The linear range,detection limit,repeatability test,recovery test and interference test).And the method was used to detect the concentration of PQ and Cr in PQ poisoned patients′urine. Results The peaks of PQ and Cr appeared within 5 min.The linear ranges of PQ and Cr were 2-1000,10-5000μmol/L,respectively,with the correlation coefficients of 0.9997 and 0.9999 (P<0.01).The detection limits were 1.0μmol/L for PQ and 5.0μmol/L for Cr.The mean within-day (n=10) CV s of peak area for PQ and Cr were 2.84% and 1.72%,while the mean inter-day (n=10) CV s of peak area were 3.62% and 3.06%.The average recovery rate of PQ and Cr were 88.6% and 90.2% respectively.Diquat (DQ) didn′t interfere with the assay.The range of PQ/Cr (μmol/mmol) for 8 cases was 8.9-2215. Conclusions A method was established successfully for the rapid determination of PQ and Cr in urine by capillary electrophoresis.The CE method devised here for direct measurement of urinary PQ and Cr from PQ poisoned patients is simple,fast,automatic and with good repeatability.It is an ideal method for rapid detection of urinary PQ in PQ poisoned patients.(Chin J Lab Med,2013,36:791-795) Key words: Electrophoresis; capillary; Urinalysis; Paraquat; Creatinine; Poisoning