Oxalate In Serum Research Articles

Solid Electrochemiluminescence Sensor by Immobilization of Emitter Ruthenium(II)tris(bipyridine) in Bipolar Silica Nanochannel Film for Sensitive Detection of Oxalate in Serum and Urine.

Convenient and highly sensitive detection of oxalate ions in body fluids is of crucial significance for disease prevention, diagnosis, and monitoring of treatment effectiveness. Establishing a simple solid-state electrochemiluminescence (ECL) sensing system for highly sensitive detection of oxalate ions is highly desirable. In this work, a solid ECL sensor was fabricated by immobilizing the commonly used emitter ruthenium(II)tris(bipyridine) (Ru(bpy)32+) on a double-layered bipolar silica nanochannel array film (bp-SNA)-modified electrode, enabling sensitive detection of oxalate ions in serum or urine samples. Cost-effective and readily available indium tin oxide (ITO) was used as the supporting electrode. Convenient fabrication of multiple negatively charged SNA (n-SNA)-modified ITO electrodes was achieved through the one-step Stöber solution growth method. Subsequently, a positive outer layer film (p-SNA) was rapidly prepared using an electrochemical-assisted self-assembly method. The double-layered bipolar silica nanochannel array film achieved stable immobilization of Ru(bpy)32+ on the electrode surface, facilitated by the electrostatic adsorption of Ru(bpy)32+ by n-SNA and the electrostatic repulsion by p-SNA. Utilizing oxalate ions as a co-reactant for Ru(bpy)32+, combined with the electrostatic enrichment of oxalate ions by p-SNA, the constructed sensor enabled highly sensitive detection of oxalate ions ranging from 1 nM to 25 μM and from 25 μM to 1 mM, with a detection limit (LOD) of 0.8 nM. The fabricated ECL sensor exhibited high selectivity and good stability, making it suitable for ECL detection of oxalate ions in serum and urine samples.

Simultaneous determination of oxalate and citrate in urine and serum of calcium oxalate kidney stone rats by IP-RP LC-MS/MS

Oxalate and citrate in 24 h urine and serum are considered to be associated with the incidence and recurrence risk of calcium oxalate kidney stones. The quantification of oxalate and citrate contributes to understand the pathological metabolism of kidney stones and guide the early diagnosis and recurrence monitoring. Although simultaneous quantification of oxalate and citrate in urine using liquid chromatography tandem mass spectrometry (LC-MS/MS) have been reported, the optimization of chromatographic column, mobile phase and mass spectrometry (MS) parameters has not been performed. In addition, these is a lack of suitable method for simultaneous detection of oxalate and citrate both in serum and urine. Therefore, we developed a method for the simultaneous determination of oxalate and citrate in urine and serum based on ion-pairing reversed-phase (IP-RP) LC-MS/MS. Herein, five ion-pair reagents, namely, triethanolamine, dimethylbutyl amine, diisopropenyl amine, N,N-dimethylcyclohexylamine and tripropylamine, and three ion-pairing reagent (IPR) buffers, namely, acetic acid, hexafluoro-2-isopropanol, and hexafluoro-2-methyl-2-propanol, were compared in regard to their chromatographic peak abundance and separation of oxalate and citrate. Moreover, MS parameters and the multiple reaction monitoring (MRM) conditions were also evaluated and optimized to obtain the maximum peak abundance. After that, the method was validated in the linear range of 0.25–1000 µM, and the correlation coefficient was ≥ 0.99. The precision and accuracy were < 14.70% and < 19.73%, respectively. The extraction recovery was 80.53–108.79%, and the matrix effect was < 8.79%. The quality control samples were stable at room temperature for 4 h, 4 °C for 24 h, and for 3 freeze–thaw cycles. Finally, this method was applied to the determination of oxalate and citrate in the serum and urine of rats with calcium oxalate kidney stones. The establishment of a stable and effective oxalate and citrate detection method is conducive to the diagnosis and monitoring of kidney stones.

Simultaneous Determination of Oxalate and Citrate in Urine and Serum of Calcium Oxalate Kidney Stone Rats by Ip-Rp Lc-Ms

Simultaneous Determination of Oxalate and Citrate in Urine and Serum of Calcium Oxalate Kidney Stone Rats by Ip-Rp Lc-Ms

Determination of Oxalate in Human Serum in the nM Range by On-Column Sample Preconcentration-Capillary Zone Electrophoresis with Direct Absorbance Detection

For determination of oxalate in serum, capillary zone electrophoresis with direct absorbance detection at 190 nm was combined with the electric field-amplified preconcentration technique. The effects of several variables (the concentration of the background electrolyte, sample dilution factor and sample size) on the sensitivity and resolution of this method were studied. Serum samples were deproteinated by centrifugal filtration through a 5 kD membrane and prior to analysis, diluted 10-fold with water. The limit of detection at S/N=3 was 1.14 nM (0.10 ppb). Linearity was established in the range of 5.68 nM-11.36 μM (0.5 ppb–1.0 ppm) with a correlation coefficient of 0.9999. Recoveries of oxalate from four spiked sera averaged 96.2%. The potential of the method developed was demonstrated by analyzing sera from several healthy adults.

Correlative study of fluoride content in urine, serum and urinary calculi

Fluoride content was measured in 100 urinary stones retrieved by open surgery of stone formers admitted at PGIMS Rohtak and their respective urine and serum and compared with those of healthy individuals. The concentration of fluoride was also measured in the sources of drinking water of these stone formers. The concentration of fluoride was definitely significantly higher in serum (p>0.01) and highly significantly higher in urine (p>-0.001) of stone formers compared to those of healthy individuals. The content of oxalate in serum and 24 h urine of the stone formers was also measured, which was increased significantly (p<0.005 and p<0.001) compared to healthy individuals. The concentration of fluoride was probably significantly higher in drinking water of these stone formers than the normal ones. There was a positive correlation between the content of fluoride of urinary stones and urine of stone patients (r=.88); stone and serum (r=.62); drinking water and stone (r=.85) and their urine and serum (r=.54); urine and drinking water (r=.83) and serum and water (r=.51). These results indicate a definite role of fluoride in urinary stone formation.

Chemiluminescent measurement of oxalate in serum by detection of hydrogen peroxide generated through oxalate oxidase.

Today, chemiluminescence detection reactions have become popular in analytical biochemistry essentially due to their high sensitivity. A chemiluminescent synthetic system (luminol/porphyrin) was successfully used to measure serum oxalate by determination of hydrogen peroxide generated through oxalate oxidase (EC 1.2.3.4.). This new method is efficient and simple, highly sensitive and the results obtained in normal adult subjects are in good agreement with those of approved methods. This original application of such a chemiluminescent system allowed us to achieve a sensitive serum oxalate assay (detection limit of 0.2 mumol/L) characterized by a low serum volume (200 microL) required for analysis.

Chemiluminescent measurement of oxalate in serum by detection of hydrogen peroxide generated through oxalate oxidase

Today, chemiluminescence detection reactions have become popular in analytical biochemistry essentially due to their high sensitivity. A chemiluminescent synthetic system (luminol/porphyrin) was successfully used to measure serum oxalate by determination of hydrogen peroxide generated through oxalate oxidase (EC 1.2.3.4.). This new method is efficient and simple, highly sensitive and the results obtained in normal adult subjects are in good agreement with those of approved methods. This original application of such a chemiluminescent system allowed us to achieve a sensitive serum oxalate assay (detection limit of 0.2 μmol/L) characterized by a low serum volume (200 μL) required for analysis. © 1997 John Wiley & Sons, Ltd.

Determination of serum oxalate using peroxyoxalate chemiluminescence of free oxalic acid.

We describe a new sensitive and specific method for determination of oxalate in human serum. By using the chemiluminescence decay of monoperoxyoxalic acid very low concentrations of oxalate (200 nmol/L) can be determined. The mean serum oxalate level in apparently healthy controls was 14.5 +/- 8.5 mumol/L. Supplementation of ascorbic acid leads to an increase in serum oxalate level. While serum oxalate concentrations of calcium oxalate stone formers (x = 16.4 +/- 9.8 mumol/L) are not significantly different from the control group, an extreme increase of serum oxalate is evident in haemodialysis patients. The serum oxalate concentration decreased during dialysis treatment from 141.4 +/- 32.1 mumol/L to 36.4 +/- 12.7 mumol/L.

Oxalate, phosphate and sulphate determination in serum and urine by ion chromatography

A rapid method for the determination of phosphate, sulphate and oxalate in serum by ion chromatography is described. Serum is deproteinized through a Centrifree filter by centrifugation and the ultrafiltrate directly injected into an ion chromatograph equipped with an anion exchange column and a conductivity detector. By this procedure the sample is not diluted and even small amounts of oxalate in biological fluids can be detected. Mean serum concentrations found in healthy individuals are: phosphate 1.07 mmol/l; sulphate 0.35 mmol/l; oxalate 21.02 μmol/1. Phosphate, sulphate and oxalate contents were also determined in urine from healthy individuals. Values found in serum and urine are in good agreement with those previously reported.

Extraction--spectrophotometric determination of oxalate in urine and blood serum.

An extraction--spectrophotometric method is described for the determination of oxalate, based on the formation of a mixed ligand vanadium (V)--mandelohydroxamic acid--oxalate complex. The complex was extracted into a solution of trioctylmethylammonium chloride (Adogen 446) in toluene and the absorbance measured at 535 nm. The experimental variables and interferences in this determination were studied. The detection limit is 0.5 microgram ml-1 and the range of application is between 2 and 8 micrograms ml-1. The method was applied to the determination of oxalate in urine and blood serum.

Determination of oxalate in human serum by multicolumn isotachophoresis.

The practical usefulness of multicolumn isotachophoresis was demonstrated by the determination of oxalate levels in human serum. 10 mmol/L HCl and 100 mmol/L Na2HPO4 served as the leading and terminating electrolyte, respectively. For the stabilization of the isotachophoretic zones in large cross section channels a suspension of Bio-Gel P-300 in the leading electrolyte was used. For the analysis ca. 1 mL of fresh serum was required and 1.2 mL of 1:1 mixture of serum and the suspension of Bio-Gel P-300 in deionized water was applied as sample. The time of analysis ranged between 45-49 min. The detection limit of analysis was determined to be 50 nmol/L. Reproducibility of analysis of 1 mumol/L oxalate in water standard was found to be 2.6% (n = 6).

In vitro oxalogenesis, and measurement of oxalate in serum.

In vitro oxalogenesis, and measurement of oxalate in serum.

A radioenzymatic isotope-dilution assay for oxalate in serum or plasma.

Journal Article A radioenzymatic isotope-dilution assay for oxalate in serum or plasma. Get access D J Bennett, D J Bennett Search for other works by this author on: Oxford Academic Google Scholar F E Cole, F E Cole Search for other works by this author on: Oxford Academic Google Scholar E D Frohlich, E D Frohlich Search for other works by this author on: Oxford Academic Google Scholar D T Erwin D T Erwin Search for other works by this author on: Oxford Academic Google Scholar Clinical Chemistry, Volume 25, Issue 10, 1 October 1979, Pages 1810–1813, https://doi.org/10.1093/clinchem/25.10.1810 Published: 01 October 1979

A new method for determination of oxalate in blood serum by gas chromatography

A method for the determination of blood oxalate by gas chromatography is described. After clarification of the serum with acetone, the oxalate was extracted, ethylated and analysed on a gas Chromatograph. The concentration of oxalate in the sample was determined by comparison with the elution pattern of diethylmalonate used as an internal standard. Using this technique, the recovery of added oxalate was more than 80%. Normal subjects were found to have blood oxalate levels of 27μmol/1 or less.