In this work, the possibility of simultaneous determination of three compounds with a single-injection step using batch injection analysis with multiple pulse amperometric detection (BIA-MPA) is demonstrated for the first time. A sequence of three potential pulses (+1.25 V, +1.
View Article and Find Full Text PDFIn this paper, we present two new electrochemical methods for fast and simultaneous determination of codeine (CO) and diclofenac (DCF). The first one is based on batch injection analysis with amperometric detection (BIA-MPA) and the second one is based on capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C(4)D). The proposed BIA-MPA method is highly-precise (RSD of 1.
View Article and Find Full Text PDFThis paper presents a method for fast and simultaneous determination of diclofenac (DCF) and its common counter-ions (potassium, sodium, and diethylammonium) using CE with capacitively coupled contactless conductivity detection (CE-C(4) D). On the basis of a single electropherogram (about 50 s), the proposed method allows the determination of the stoichiometry, absolute quantification and evaluation of the degradation degree of the active pharmaceutical ingredient (DCF). A linear working range from 100 to 500 μmol/L was obtained for all analytes in an equimolar TRIS/TAPS (10 mmol/L) solution as the background electrolyte as well as adequate LOD (7, 6, 7, and 10 μmol/L for K(+) , Na(+) , diethylammonium, and DCF, respectively).
View Article and Find Full Text PDFWe report here, for the first time, application of batch injection analysis (BIA) with amperometric detection for determination of the phenolic antioxidant butylated hydroxyanisole (BHA) in biodiesel. A sample plug was directly injected onto a boron-doped diamond electrode immersed in 50% v/v hydroethanolic solution with 0.1 mol L(-1) HClO(4) using an electronic micropipette.
View Article and Find Full Text PDFThe direct amperometric determination of tert-butylhydroquinone (TBHQ) in biodiesel at an unmodified glassy carbon electrode is reported. A biodiesel aliquot was added into an electrochemical cell containing a 75% (v/v) ethanol-water solution under stirring (with final concentration of 50 mmol L(-1) HClO(4)). The amperometric method involved the continuous application of three sequential potential pulses to the working electrode (700 mV for 300 ms, 0 mV for 100 ms and -50 mV for 1s).
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