New electrochemical sensors for detection of nitrites and nitrates

Abstract

Platinum electrodes modified with a cellulose acetate membrane or with poly(1,8-diaminonaphthalene) film were assembled and used for rapid amperometric detection of nitrites and nitrates in water by batch and flow injection analysis.Parameters such as the permeability of the electropolymerised films to nitrites and nitrates, interference effects and recovery studies of these kinds of sensors have been optimised to demonstrate the analytical suitability of the proposed method.Contrary to the standard colorimetric method, which is based on carcinogenic reagents, the amperometric detection of nitrites and nitrates is very simple and rapid and does not require any reagent for nitrite detection. Also, this method could be extended easily to the analysis of nitrites and nitrates in various types of samples such as food, soils, vegetables and fertilisers.

A simple and sensitive spectrophotometric method for the determination of trace amounts of nitrite in environmental and biological samples using 4-amino-5-hydroxynaphthalene-2,7-disulphonic acid monosodium salt

“…There are numerous methods developed so far for the determination of nitrite in environmental samples, which include spectrofluorometry [10][11][12], chromatography [13][14][15][16], potentiometry [17][18][19], capillary electrophoresis [20][21][22], membrance sensors [23,24], flow injection analysis [25][26][27][28][29], electroanalytical [30,31], and amperometric [32,33]. Most of these methods are not suitable for routine determination of nitrite in environmental samples because some of them are costly or need skilled person to handle.…”

Synthesis and characterization of polymeric films and nanotubule nets used to assemble selective sensors for nitrite detection in drinking water

“…After rinsing with distilled water, the electrodes were pre-treated by potential cycling in 0.5 M H 2 SO 4 from −0.2 to +1.2 versus Ag|AgCl at a scan rate of 20 mV/s, until no changes were observed in the cyclic voltammograms [12].…”

“…Film permeability was evaluated measuring the peak current by cyclic voltammetry for each analyte. Then the permeability (P%) was calculated using the equation (1), as described in [12]:…”

“…In this work, platinum electrodes were covered by different electropolimerized barriers which have size exclusion properties and which have been synthetized by two different techniques: polymeric films traditionally [12] obtained by cyclic voltammetry and polymeric nanotubule nets obtained by "template synthesis" approach [13]. Permeability toward nitrites and interferences and the correspondent permselectivity were evaluated.…”

The Detection of Nitrate Using in-situ Copper Nanoparticle Deposition at a Boron Doped Diamond Electrode

“…Polarography is often employed 1,3,28,29 and this and other electrochemical methods are used in conjunction with other regimes such as high performance liquid chromatography. 4,[6][7][8][30][31][32] Electrochemical detection is mostly performed at copper modified electrodes [33][34][35][36][37][38][39][40][41][42][43][44][45][46] although other electrodes such as Pt modified with cellulose acetate membrane, 47 gold plated porous membrane, 48 yeast modified glassy carbon 49 and yeast modified screen printed carbon 49 have been investigated. Ion selective electrodes can be used to avoid the effects of common interferences.…”