An enzyme-spectrophotometric method to determine citrate in biological fluids is proposed, based on citrate lyase-catalyzed and phenylhydrazine reactions. The enzyme converts citrate into oxaloacetate, which, in the presence of phenylhydrazine, is transformed into the corresponding phenylhydrazone. The ultraviolet-absorbing product is determined by absorbance measurement at 330 nm. The method i...

Abstract A sensitive method for the determination of citrate and malate in sub-microliter samples of soil solution is described. The organic acids were derivatized with a pyrene reagent (1-pyrenebutanoic acid hydrazide) and analysed by micellar electrokinetic chromatography separation. The citrate and malate derivatives were detected within 10 min by using a fluorescence detector with a broad e...

We describe an enzymic method for conveniently measuring citrate in serum or urine. Interfering enzyme proteins are removed by a disposable ultrafilter ("Ultrafree"; Worthington Diagnostics), obviating the need for hazardous protein precipitants. A 50 mmol/L Tris buffer adequately controls pH, no lactate dehydrogenase is necessary in the reagents, and the reaction of citrate catalyzed by citrat...

Abstraet--A new iron oxide dissolution method designed to measure the abundance of "free" Fe oxide phases and associated elements in soils and sediments has been tested. The method employs a ternary complex of Ti(III), citrate, and ethylenediaminetetraacetate (EDTA) as a reductant and bicarbonate as a proton acceptor. The Ti(III)-citrate-EDTA-HCO3 method dissolved more synthetic amorphous ferri...

We describe a method for measuring urinary oxalate and citrate with capillary electrophoresis (CE) and indirect ultraviolet absorbance detection. Sample preparation is minimal, requiring an acidification, brief centrifugation, and dilution. The method is rapid, with oxalate and citrate having mean migration times of 4.02 and 4.50 min, respectively. The minimal detectable concentration (signal-t...

BACKGROUND Regional citrate anticoagulation is a very effective anticoagulation method for haemodialysis. However, it is not widely used, primarily due to the risk of hypocalcaemia. We studied citrate and calcium kinetics to better understand safety aspects of this anticoagulation method. METHODS During 15 haemodialysis treatments with a calcium-free dialysis solution, citrate was infused pre...

in this work, we report synthesis of surface modified superparamagnetic iron oxide nanoparticles (spion) by co-precipitation method using feso4.7h2o and fe2(so4)3.5h2o as precursors and trisodium citrate dihydrate as surfactant. surface modification of the as prepared samples was performed in pot by sol-gel precipitation method using tetraethoxysilane (teos). the structure, morphology, and magn...

Butamirate citrate is a non-narcotic cough suppressant. A straightforward and accurate analytical method is indispensable for the assay of butamirate citrate for the pharmaceutical industry. In the present study, a high performance liquid chromatography (HPLC) method with UV detection was developed and validated for the estimation of butamirate citrate from tablet and syrup formulations. 1:1 v/...

The interactions between pig heart citrate synthase and mitochondrial malate dehydrogenase or cytosolic malate dehydrogenase were studied using the frontal analysis method of gel filtration and by precipitation in polyethylene glycol. This method showed that an interaction between citrate synthase and mitochondrial malate dehydrogenase occurred but no interaction between citrate synthase and cy...