Laser-Heating Thermal Modulation Voltammetric Determination of Phosphate Ion Using a Graphite-Reinforced Carbon Electrode

Abstract

12O40]3-), was formed through a reaction between a phosphate ion and molybdate ions in an acidic solution, and its electroreduction was examined in a flow electrolytic cell by TM voltammetry. Measured TM voltammograms showed two peaks corresponding to two successive two-electron reductions of the 12-molybdophosphate ion, and the peak intensities were proportional to the concentration of the phosphate ion. Because of the strong adsorption of 12-molybdophosphate ion onto the GRC electrode, a detection limit as low as 0.8 nmol dm -3 (S/N = 3) was achieved. The determination of phosphate ion in real samples (river water) was carried out by spectrophotometry (the molybdenumblue method) and TM voltammetry, and the determination values obtained by both methods were in a good agreement with each other. These results prove the possibility of TM voltammetry as an electroanalytical method.

Energy‐Dispersive X‐Ray Fluorescence Spectrometric Determination of Phosphate in Water Samples via a 12‐Molybdophosphate–Crystal Violet Complex

“…There have been a number of methods for determining orthophosphates in water samples including inductively coupled plasma-optical emission spectrometry (ICP-OES) [2], inductively coupled plasma-mass spectrometry [3], chemiluminescence [4,5], fluorimetry [6,7], capillary electrophoresis [8], voltammetry [9,10], potentiometry [11], and amperometry [12]. However, spectrophotometric methods for phosphate determination are the most widely used [13][14][15][16][17][18][19], often in conjunction with flow injection analysis [20,21] or cyclic injection analysis [22,23].…”

Directly suspended droplet microextraction combined with energy-dispersive X-ray fluorescence spectrometry to determine nano levels of phosphate in surface water

“…Moreover, the determination of phosphorus in surface waters can provide essential data for assessing the health of ecosystems, investigating biogeochemical processes and monitoring compliance with legislation. 1,2 For the determination of phosphate in water, the method based on the formation of molybdenum blue complex, proposed by Murphy and Riley, 3 is still the most commonly employed standard method by manual batch procedures as well as by automated instrumental systems 4 using various instrumental techniques such as spectrophotometry, [5][6][7][8][9][10][11][12][13][14] amperometry, 15 voltammetry, 16 or ion pair liquid chromatography. 17 Determination of trace elements with low atomic number such as phosphorus by X-ray fluorescence spectrometry (XRF) is hampered because of the low fluorescence yield and relatively low energy of characteristic radiation (strong absorption by the sample matrix).…”