Electroanalytical Determination of Lidocaine in Pharmaceutical Preparations Using Boron‐Doped Diamond Electrodes

Abstract

A new electroanalytical procedure was developed for the determination of lidocaine in commercial local anesthetics products containing lidocaine as the active ingredient. The procedure is based on the use of electrochemical methods as cyclic and square-wave voltammetry, with boron-doped diamond electrodes. The oxidation of lidocaine in BrittonRobinson buffer (0.1 mol L À1 ) using this type of electrode gives rise to one irreversible peak in 1.68 V (versus Ag/ AgCl). The detection and quantification limits obtained from pure water were 10.0 and 34.4 mg/L, respectively. The proposed electrochemical method was also successfully applied to the analysis of commercially available pharmaceutical preparations. The electrochemical responses of pharmaceutical preparations (gels) were identical to those of standard lidocaine. No influence of propyleneglycol present in the gels on the voltammetric responses was observed. Lidocaine recoveries ranged from 97.6% to 99.2%.

Analytical Determination of Benzophenone-3 in Sunscreen Preparations Using Boron-Doped Diamond Electrodes

“…The BDD electrode was glued onto a copper plate using a silver paste as previously reported in the literature [49,50]. The copper plate and the BDD edges were later isolated with Araldite ® resin, leaving an exposed area of 0.025 cm 2 .…”

“…These results stress the need for performing ca-thodic pre-treatment just before the electrochemical ex-periments are conducted, in order to ensure reliable and reproducible results. In the literature there are several papers that used BDD electrode cathodically pretreated for electroanalytical applications [45,46,[49][50][51]. Thus, before each analysis the BDD electrodes were pre-treated at + 3.2 V, in order to oxidize possible adsorbed species on the electrode surface, and after at -2.8 V (vs. Ag/AgCl), 30 s each, in HClO 4 solution (0.1 mol·L -1 ).…”

“…The combination of square-wave voltammetry (SWV) and BDD electrodes has proved to be an interesting and desirable alternative for the analytical determination of some organic molecules [49,50]. So, in view of the lack of a simple and direct electroanalytical method for the determination of BENZO, the purpose of this investigation is the development of an electrochemical method capable of directly quantifying BENZO in commercial pharmaceutical preparations available in sunscreen form, using cyclic voltammetry and SWV with BDD as the working electrode.…”

“…Recent studies reported in the literature have shown that several inorganic, organic and biomolecules can be satisfactorily determined with the use of BDD electrodes [32,[47][48][49].…”

Validated Selective HPLC-DAD Method for the Simultaneous Determination of Diclofenac Sodium and Lidocaine Hydrochloride in Presence of Four of Their Related Substances and Potential Impurities

“…Several reports can be found in the scientific literature for determination of LD. Examples of the published analytical methods are electrochemical methods [16], spectrophotometry [17], capillary zone electrophoresis with diode array detection (DAD) [18], CE with electrochemiluminescence detection [19], GC with nitrogen phosphorus detection [20], and HPTLC [21]. Liquid chromatography has been utilized for the estimation of LD.…”