Selective UV-filter detection with sensors based on stainless steel electrodes modified with polyaniline doped with metal tetrasulfonated phthalocyanine films

Abstract

This work describes the construction and application of two amperometric sensors for sensitive UV-filter determination. The sensors were prepared using stainless steel electrodes in which polyaniline (PANI) was electrochemically polymerized in the presence of nickel (NiPcTS) or iron (FePcTS) tetrasulfonated phthalocyanines. The sensor surface characterizations were carried out using atomic force microscopy (AFM). The PANI/NiPcTS sensor was selective for the chemical UV-filter p-aminobenzoic acid (PABA) and the PANI/FePcTS sensor was selective for octyldimethyl-PABA (ODP), both in a mixture of tetrahydrofuran (THF) and 0.1 mol L(-1) H2SO4 at a volume ratio of 30 : 70, and with an applied potential of 0.0 mV vs. Ag|AgCl. A detailed investigation of the selectivity was carried out for both sensors, in order to determine their responses for ten different UV filters. Finally, each sensor was successfully applied to PABA or ODP quantification in sunscreen formulations and water from swimming pools.

First application of carbon-based screen-printed electrodes for the voltammetric determination of the organic UV filters oxybenzone and octocrylene

“…L.H. Wang used voltammetry at mercury film electrodes to determine some UVF substances in cosmetics [27], L.F. Moreira et al developed amperometric sensors based on polyaniline immobilised in stainless steel electrodes [28], and the group of V.S. Ferreira applied differential pulse and square wave adsorptive stripping voltammetry (AdSV) at mercury drop [29][30][31] and glassy carbon [32] electrodes to determine up to three sunscreen agents in commercial preparations.…”

Analytical chemistry in Brazil: healthy and growing

“…The authors modified indium tin oxide glass electrodes and combined it with gold nanoparticles and poly(vinylsulfonate). Moreira et al 236 described the construction and application of two amperometric sensors for sensitive determination of p-aminobenzoic acid (a UVfilter) and the sensor surface characteristics was observed using atomic force microscopy (AFM).…”

Cobalt phthalocyanine as a biomimetic catalyst in the amperometric quantification of dipyrone using FIA

“…Biomimetic sensors are more sensitive, compared to enzymatic biosensors, due to a smaller diffusion barrier and greater electron transfer between the biomimetic complex and the analyte [6,7]. This new and increasingly popular class of sensors has been used for the identification and quantification of various drugs [13][14][15][16][17], and has also been coupled to flow systems [18,19].…”

“…Although all of the P450 enzymes contain a common active site, namely the iron porphyrin complex, the selectivity of each P450 is a consequence of the chemical environment surrounding the hemin group [20]. As a result, compounds derived from phthalocyanines and porphyrins of iron [13,18,19,22,23], or other metals such as manganese [14], nickel [15] and copper [17], have been successfully used in the construction of biomimetic chemical sensors for a variety of analytical purposes.…”