EFFECT OF MODEL ORGANIC-COMPOUNDS ON POTENTIOMETRIC STRIPPING ANALYSIS USING A CELLULOSE-ACETATE MEMBRANE-COVERED ELECTRODE

The effects of model surfactants (sodium dodecyl sulfate, Triton X-100), proteins (ovalbumin, gelatin), and carbohydrates (agar, starch) as well as D-camphor and humic acid on a cellulose acetate dialysis membrane-modified mercury film electrode (CM-MFE) in potentiometric stripping analysis (PSA) are described. The CM-MFE (1000 amu molecular weight cutoff) minimized interference by these compounds to the PSA measurement. The constant current stripping analysis (CCSA) mode was found to provide a more stable response than the use of Hg(II) as chemical oxidant with the CM-MFE. Results presented for urine and natural water samples demonstrate the analytical utility of the CM-MFE in PSA.