Ion Selective Electrodes And Their Applications In Research Of Urinary Stone

The electrodes of chloride ion pH oxalic acid citric acid and so on were prepared based on PVC membrane. These electrodes have been used to determine the compositions in urine and simulated systems. The electrode's characteristics were discussed.The chloride ion selective electrode was prepared based on PVC membrane using chloride-cetyltrisooctylammium ion-pair complex as electroactive material. The linear range of chloride ions was 1.0 10-3~ 1.0 mol L-1, average slope 47 mV/pC. The electrode is stable and has a good reproducibility. It can be used to determine the concentration of chloride ion in diluted urine and in artificial urine.PVC membrane pH electrode was prepared and used in acidic condition based on sodium tetraphenylborate-uric acid ion pair as electroactive material. This electrode showed Nernst response to H' ion in the range of pH 1.0~7.0 with a slop of 50.5 mV/pH. Experiment indicates that the electrode has fair stability and reproducibility. It was successfully applied to the determination of beverage, tap water and artificial urine.Both oxalic acid and citric acid can create stable complexes with trioctylamine (TOA). The complex ratios were confirmed to be 1:1 by chemical analyse and FT-IR spectra. The PVC membrane electrodes based on these electroactive materials were prepared. These electrodes can determine the concentrations of oxalic acid and citric acid. The linear ranges were from 10-4 to 10-1 mol L-1 for oxalate acid and from 10-5 to 10-2 mol L-1 for citrate. The electrodes were successfully applied to determine the concentrations of oxalic acid and citric acid in simple simulative systems.The simultaneous determination of Ca and Mg in urine by flame atomic absorption spectrometry was investigated. The optimized working conditions of Ca and Mg were ascertained. The difference of concentrations of Ca and Mg in urine between the healthy and the stone patients was discussed.