The development of a FIA system for the determination of total choline content in several types of milk is described. The samples were submitted to hydrochloric acid digestion before injection into the system and passed through an enzymatic reactor containing choline oxidase immobilised on glass beads. This enzymatic reaction releases hydrogen peroxide which then reacts with a solution of iodid...

An integrated computer system consisting of an expandable ionanalyzer and a PC has been used to automate concentration measurements with ion-selective electrodes (ISEs). The ionanalyzer determines ionic concentrations using a reference electrode coupled with an ISE. The measurements and calibrations are carried out in a thermostated sample changer equipped with a flow cell. The data obtained by...

As a part of studies concerning clinical application of the measurement of urinary iodide with an iodide-selective ion electrode, we report here the reference values for the iodide content or concentration in morning spot urine specimens from normal subjects of varying ages and studies with patients with thyroid diseases in Japan. The number distribution of the iodide content or concentration i...

Potentiometric investigation on {H2O+NaNO3+PEG1500} mixtures were made at T=308.15K, using electrochemical cells with two ion-selective electrodes, (Na+ glass) as the cation ion-selective electrode against (NO3- solvent-polymer PVC) as the anion ion-selective electrode. The mean ionic activity coefficients of NaNO3 were measu...

A PVC ion-selective membrane electrode based on Cd-tetraphenyl porphyrine as a carrier was prepared fordetermination of MnO4- ion. This electrode revealed good selectivity toward permanganate ion over a widevariety of anions. Effects of some experimental parameters such as nature of the plasticizer, the amounts ofcarrier and additive, and concentration of the internal solution on the potential ...

a nanocomposite membrane cu2+ ion-selective electrode has been constructed using a new compound ethyl 1,2,3,4-tetrahydro-4-(4-methoxyphenyl)-6-methyl-2-oxopyrimidine-5-carboxylat (etmoc) as a neutral ionophore. the electrode works properly. it responds to cu2+ ion with a sensitivity of 29.5 ± 0.2 mv/decade over the range 1.0 × 10−9 to 5.0 × 10−1m at ph 3.0-8.0. the limit of detection was 4.5 × ...

A portable vacuum interface allowing direct probing of the electrode-electrolyte interface was developed. A classical electrochemical system consisting of a gold working electrode, platinum counter electrode, platinum reference electrode, and potassium iodide electrolyte was used to demonstrate real-time observation of the gold iodide adlayer on the electrode and chemical species as a result of...