Ungureanu, Eleonora-MihaelaEleonora-MihaelaUngureanuVasile, GabrielaGabrielaVasileArnold, Georgiana LuizaGeorgiana LuizaArnoldBirzan, LiviuLiviuBirzanBuica, George OctavianGeorge OctavianBuica2018-01-152018-01-152017978-619-7408-08-91314-270410.5593/sgem.2017/51http://hdl.handle.net/123456789/112717th International Multidisciplinary Scientific Geoconference SGEM 2017, Conference Proceedings, Ecology and Environmental Protection, Vol. 17, Issue 51, pp. 359-364, 29 June - 5 July 2017, Albena, BulgariaThe purpose of the study was to develop an electrochemical method for detection of lead at low level of contamination in water samples using a carbon glassy electrode modified with the functionalized azulene: (2E)-2-(azulen-1-ylmethylidene) hydrazine carbothioamide (L) as a complexing polymer film. The modified electrodes were prepared in L solutions (1mM) in acetonitrile (CH3CN) containing tetra n-butyl ammonium perchlorate (0.1 M TBAP) as supporting electrolyte. The analyses were performed on Autolab PGSTAT 12 Potentiostat, all the reagents used were ultratrace quality. The electrochemical method include four steps: 1) polymeric film formation by controlled potential electrolysis (CPE) at 1.7V using a charge of 1 mC under argon atmosphere; 2) film conditioning in 0.1 M buffer acetate solution using cyclic voltammetry; 3) complexation in a standard solution prepared from lead nitrate (II) using ultrapure water as matrix or a real sample; 4) stripping differential pulse voltammetry method (DPV) in acetate buffer at 5.5 pH, after 180 seconds reduction time at a reduction potential of -1.2 V. The determination time for a standard solution or real sample is around 45 minutes. The calibration curve was plotted in the range 1 to 50 µg/L Pb (II). The precision experiments were performed at 10 µg/L Pb (II). The precision for polymeric film formation on the glassy carbon electrode was 13.5%, while the intermediate precision test indicated a value of 15.5%. Evaluation of the method performant parameters confirm that the proposed method is suitable to detect and quantify lead content in water samples.en-USLeadWaterStripping voltammetryPolymeric filmPoly[(2E)-2-(azulen-1- ylmethylidene) hydrazine carbothioamide]Conference paper