Selective determination of mefenamic acid in the presence of 1000-fold excess paracetamol and caffeine using a multiwalled carbon nanotube–polymer composite electrode

Abstract

ARTICLE This journal isThis article describes the selective and sensitive determination of Mefenamic acid (MA) using carboxylated multiwalled carbon nanotubes (FMWCNTs) -nanostructured conducting polymer (p-ATT) composite modified glassy carbon (GC) electrode in 0.2 M phosphate buffer solution (PBS, pH 7.2). The bare GC electrode failed to show a stable response for MA oxidation due to the surface fouling caused by the oxidized product of MA. However, the FMWCNTs/p-ATT composite electrode showed 2.4-fold higher oxidation current with 70 mV less positive potential for MA when compared to bare GC electrode. The higher electrocatalytic activity of MA at composite modified electrode may be due to the hydrogen bonding and electrostatic interactions between p-ATT and MA besides the π-π interaction between the FMWCNTs and p-ATT. Further, the FMWCNTs/p-ATT composite electrode showed extreme selectivity towards MA in the presence of 1000-fold excess of paracetamol (PA) and caffeine (CAF) and 3330-fold excess of other common interferences. The amperometric current response was increased linearly with increasing MA concentration in the range of 40-5000 nM with a correlation coefficient of 0.9980 and the limit of detection was found to be 90 pM (S/N=3). The practical application of the present modified electrode was successfully demonstrated by determining MA in commercial drug samples.

Electro-sensing base for mefenamic acid on a 5% barium-doped zinc oxide nanoparticle modified electrode and its analytical application

“…In the past few years, a few reported methods for MFA determination have become available which include spectrophotometry, 35,36 uorimetry, 37,38 potentiometry, 39,40 chromatography, 41,42 chemiluminescence, 43,44 and capillary electromigration. 45,46 In addition, reported electrochemical methods include the use of a cobalt hydroxide modied glassy carbon electrode, 47 a multiwalled carbon nanotube-polymer composite electrode 48 and a carbon nanotube-gold nanoparticle composite lm modied electrode. 49 In the present work, Ba doped ZnO nanoparticles were synthesized and characterized using XRD, EDX, SEM and TEM.…”