Very fast electrophoretic determination of creatinine and uric acid in human urine using a combination of two capillaries with different internal diameters

Abstract

A capillary system formed by combining 25 and 100 μm id capillaries was used in the short-end injection mode to determine creatinine and uric acid in human urine. The separation was performed at an electric field intensity of 2.3 kV/cm. Creatinine was determined in a BGE with a composition of 20 mM citric acid/NaOH (pH 3.0), and uric acid was determined in 20 mM MES/NaOH (pH 6.0). Under these conditions, migration times of 12.2 s for creatinine and 8.6 s for uric acid were achieved. The LOD value is 2.4 mg/L for creatinine and 0.9 mg/L for uric acid; the RSD for the migration time varies in the range 0.7-1.1% (intra day) to 1.0-7.5% (inter day); RSDs for the peak areas equalled 3.4-4.0% (intra day) and 4.3-4.7% (inter day). The determined creatinine values in seven urine samples vary in the range 221-1394 mg/L for creatinine and 87-615 mg/L for uric acid. t-Test did not reveal any statistically significant difference between the developed CE methodologies and reference methods - Jaffé reaction for creatinine and enzymatic uricase test for uric acid.

A facile low-cost enzymatic paper-based assay for the determination of urine creatinine

“…Therefore, the Jaffe assay has been widely replaced by enzymatic methods [16]. In addition to enzymatic methods, numerous creatinine assays have been developed, such as high performance liquid chromatography (HPLC) [17], capillary electrophoresis [18], isotope-dilution mass spectrometry (IDMS) [19], tandem mass spectrometry [20], flow injection analysis [21], sequential injection analysis systems [22], microfluidic systems [23], zone fluidic multichannel kinetic spectrophotometry [24], surfaceenhanced Raman spectroscopy [25] and antibody-based sensors [26]. However, these methods are not commonly used in general laboratoriesbecause they require expensive instruments and are cumbersome for routine use [17,19].…”

Fast separation of enantiomers by capillary electrophoresis using a combination of two capillaries with different internal diameters

“…The technique of joining two capillaries with different internal diameters developed by Pavlíček et al . was used to prepare connected capillaries.…”

Simultaneous determination of renal function biomarkers in urine using a validated paper-based microfluidic analytical device

“…In this test, alkaline picrate reacts with creatinine to form an orange-red product that is measured spectrophotometrically. Other current methods include HPLC-MS/MS [2], HPLC-DAD [3,4], spectrophotometry [5], spectrophotometry using a portable microfluidic system [6], and electrophoresis with electrochemical [7], UV [8], and colorimetric detection [9].…”