A sensitive determination of acetaminophen in pharmaceutical preparations and biological samples using multi-walled carbon nanotube modified glassy carbon electrode

Abstract

Um eletrodo quimicamente modificado foi construído, baseado em eletrodo de carbono vítreo modificado por nanotubos de carbono de paredes múltiplas (ECV-NTCPM). O uso deste sensor na determinação de acetaminofeno (ACT), em meio aquoso tamponado, foi demonstrado. As medidas foram realizadas com utilização dos métodos de voltametria de pulso diferencial (VPD), voltametria cíclica (VC) e cronoamperometria (CA). A aplicação de VPD mostrou dois intervalos dinâmicos lineares. O primeiro intervalo dinâmico linear foi de 0,1 a 22 μmol L -1 , com equação de calibração Ip(μA) = 1,2782c (mmol L -1 ) + 0,2431 (R 2 = 0,9984) e o segundo intervalo dinâmico linear foi entre 26 e 340 μmol L -1 com equação de calibração Ip(μA) = 0,7793c (mmol L -1 ) + 11,615 (R 2 = 0,9986). O limite de detecção de 0,029 μmol L -1 (S/N = 3) foi obtido. O eletrodo modificado mostrou respostas eletroquímicas com alta sensitividade, excelente seletividade e estabilidade para determinação de ACT em condições ótimas, o que o torna um sensor adequado para detecção submicromolar de ACT em soluções. O desempenho analítico deste sensor foi avaliado para detecção de ACT em soro humano, urina humana e em preparações farmacêuticas com resultados satisfatórios.A chemically modified electrode is constructed based on multi-walled carbon nanotube modified glassy carbon electrode (MWCNTs/GCE). It was demonstrated that this sensor could be easily used for determination of acetaminophen (ACT) in aqueous buffered media. The measurements were carried out by application of differential pulse voltammetry (DPV), cyclic voltammetry (CV) and chronoamperometry (CA) methods. Application of DPV method showed two linear dynamic ranges. The first linear dynamic range was from 0.1 to 22 μmol L -1 , with a calibration equation of Ip(μA) = 1.2782c (mmol L -1 ) + 0.2431 (R 2 = 0.9984) and the second linear dynamic range was between 26 to 340 μmol L -1 with a calibration equation of Ip(μA) = 0.7793c (mmol L -1 ) + 11.615 (R 2 = 0.9986). A detection limit of 0.029 μmol L -1 (S/N = 3) was obtained. The modified electrode showed electrochemical responses with high sensitivity, excellent selectivity and stability for ACT determination at optimal conditions, which makes it a suitable sensor for submicromolar detection of ACT in solutions. The analytical performance of this sensor has been evaluated for detection of ACT in human serum, human urine and a pharmaceutical preparation with satisfactory results.Keywords: acetaminophen, carbon nanotube, modified glassy carbon, electrochemical sensor IntroductionAcetaminophen (N-acetyl-p-aminophenol) (ACT), also known as paracetamol, is a drug with antipyretic and analgesic action, frequently used in therapy and which has low toxicity when used at the recommended doses. 1 Nevertheless, the ease with which ordinary people can access this drug makes it frequently associated with overdoses, in this situation causing serious or even fatal hepatic damage. 2 An overdose of ACT can lead to the accumulation of toxic metabolites, which may cause severe an...

MWCNT–CTAB modified glassy carbon electrode as a sensor for the determination of paracetamol

“…Fig. Referring to the analytical performances of some recently published reports [43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58] (Table 2), it is found that the obtained detection limit in this work is lower than other modified electrodes, which is likely related that MWCNT-CTAB have high electrocatalytic and surface area effects. 6(b)).…”

Development of a Method for a Sensitive Simultaneous Determination of Dopamine and Paracetamol in Biological Samples and Pharmaceutical Preparations

“…The subtle electronic behavior of CNTs reveals that they have a high electrocatalytic effect when used as an electrode [2]. Recently, a carbon nanotube-modified solid electrode has attracted much attention because of its excellent electrochemical properties.…”

Investigating properties of poly (ether‐amide)/MWCNT nanocomposite films containing 2,7‐bis(4‐aminophenoxy)naphthalene and isophthalic segments

“…Nyquist plots were obtained when the CPEs were modified with PEA, PEA/MWCNT 2 wt.%, 3 wt.%, and 5 wt.% and immersed in a 0.1 M KCl solution containing both 5 mM of K 3 [Fe(CN) 6 ] and K 4 [Fe(CN) 6 ]. The semicircle diameter of EIS is considered to be equal to R ct (charge transfer) in Nyquist diagram . Accordingly, the results showed that the diameter of the semicircle for the CPE modified with PEA/MWCNT 5 wt.% was smaller than that of the CPE modified with PEA/MWCNT 2 and 3 wt.% (Figure ).…”