7 documents found, page 1 of 1
Uncured Polydimethylsiloxane as Binder Agent for Carbon Paste Electrodes: Appli...
Araújo,Diele A. G.; Pradela-Filho,Lauro A.; Santos,Allyson L. R.; Faria,Anizio M.; Takeuchi,Regina M.; Karimi-Maleh,Hassan; Santos,André L.This study describes the use of uncured polydimethylsiloxane (PDMS) as a binder agent to prepare carbon paste electrodes (CPEs). A comparative study between the properties of CPEs prepared with PDMS and mineral oil Nujol®, the most common binder agent for CPEs, was carried out. Cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometry showed that PDMS-CPEs presented higher electrical con...
AVALIAÇÃO DO PERFIL DE LIBERAÇÃO DO FÁRMACO IBUPROFENO EM MEMBRANAS SIMÉTRICAS ...
Ferreira,Marcos V.; Pradela Filho,Lauro A.; Santos,André L. dos; Takeuchi,Regina M.; Assunção,Rosana M. N. deCellulose derivatives still receive special attention in today biomedical applications due to their biocompatibility, ability to form resistant membranes and compatibility with various bioactive agents. In this work, cellulose acetate (CA) was used to prepare membranes with different morphologies aiming to evaluate the release profile of the drug ibuprofen (IBF). The IBF incorporation was performed by the addit...
Voltammetric Determination of Zn2+ in Antiseptic Dusting Powder and Multivitami...
Fonseca,Wilson T.; Ribeiro,Leandro A. R.; Pradela-Filho,Lauro A.; Takeuchi,Regina M.; Santos,André L.This work presents a voltammetric method for Zn2+ determination in antiseptic dusting powder and multivitamin commercial samples, combining an alkaline extraction using NaOH aqueous solution with a carbon paste electrode chemically modified with Bi anchored on Amberlite® IR120 ion exchange resin (CPEAmb/Bi). The best conditions for electrode preparation were: 10% (m/m) of Amberlite® IR 120; 30 s Bi3+ accumulati...
COMPARAÇÃO DE PROCESSAMENTOS MATEMÁTICOS DE DADOS VOLTAMÉTRICOS: APLICAÇÃO NA D...
Oliveira,Luiz H. de; Pradela,Lauro A.; Santos,André L.; Takeuchi,Regina M.; Trindade,Magno A. G.This paper describes a comparative study between the procedures of deconvolution and the second-order derivative of square wave voltammograms to achieve separation of the voltammetric peaks of levofloxacin (LEVO) and norfloxacin (NOR), for their simultaneous quantification in urine samples. The obtained results indicate that the use of second-derivative voltammograms coupled with carbon screen-printed electrode...
Desenvolvimento de um sistema de análise por injeção em fluxo utilizando materi...
Moreira,Bruna C. S.; Takeuchi,Regina M.; Richter,Eduardo M.; Santos,André L.This work describes a simple and inexpensive flow injection analysis system in which gravity force provides fluid propulsion while needles for insulin administration or metallic wires act as electrodes for amperometric detection. The proposed system was able to demonstrate the influence of several operational parameters on the transient signals. Moreover, this system was successfully used to evaluate both the s...
Study of the electrochemical reduction of amoebicide teclozan and its amperomet...
Santos,André L.; Takeuchi,Regina M.; Stradiotto,Nelson R.; Esteves,Ana Paula; Medeiros,Maria JoséThe electrochemical reduction of amoebicide Teclozan (TEC) was studied on a glassy carbon electrode in acetonitrile. Controlled-potential electrolyses were performed for coulometric and preparative purposes. The electrogenerated products were isolated by liquid-liquid extraction and characterized by ¹H NMR. It was observed that TEC presents two voltammetric peaks, each one associated with the cleavage of two C-...
Electrochemical reduction and voltammetric determination of diloxanide furoate ...
Santos,André L.; Takeuchi,Regina M.; Stradiotto,Nelson R.The electrochemical reduction of diloxanide furoate (DF) in acetonitrile on glassy carbon electrode was studied in this work. It was observed that DF is reduced after a reversible one-electron transfer followed by an irreversible chemical reaction, diagnosed as C-Cl bond cleavage. Its reduction was followed by linear (LSV), differential pulse (DPV) and square wave voltammetry (SWV). Analytical curves were obtai...