Abstract
Formaldehyde, after in situ conversion to an ionic derivative with Girard's reagent T, was first accumulated on a Nafion-coated mercury film electrode. The adsorbed derivative was then determined in aqueous solution using differential-pulse voltammetry. A single peak centred at -1.24 V (versus Ag-AgCl) was observed at pH 9.7 when using 0.4 mol l-1 NH4Cl-NH3 as the supporting electrolyte. The calibration graphs were rectilinear over the range from 2.0 × 10-7 to 1.0 × 10-5 mol l-1 formaldehyde. By incorporating a preconcentration step via the Nafion-modified electrode, the detection limit of the method for formaldehyde was calculated to be 3.4 × 10-8 mol l-1. The reproducibility and lifetime studies of the electrodes indicated that a newly prepared electrode could be repeatedly used for more than ten measurements with satisfactory precision. In addition, the method can be extended, without any modification, to the determination of acetaldehyde.
Original language | English |
---|---|
Pages (from-to) | 1727-1730 |
Number of pages | 4 |
Journal | Analyst |
Volume | 121 |
Issue number | 11 |
DOIs | |
Publication status | Published - Nov 1996 |
Scopus Subject Areas
- Analytical Chemistry
- Biochemistry
- Environmental Chemistry
- Spectroscopy
- Electrochemistry
User-Defined Keywords
- Differential-pulse voltammetry
- Formaldehyde determination
- Girard's reagent T
- Nafion-modified electrode
- Organic analysis