dc.description.abstract |
In this study, glassy carbon electrode (GCE) modified potentiodynamically by
poly(diaquabis(1,10-phenanthroline)copper(II)chloride) (poly(A2P2CuC)) is reported for the
detection of aspirin in tablet formulation. The improved effective electrode surface area
calculated from the effect of scan rate on current response for Fe(CN)6]
3-/4-
and the charge
transfer resistance result from electrochemical impedance data confirmed surface modification
of the glassy carbon electrode by a conductive poly(A2P2CuC) film. APPEARANCE OF AN
OXIDATIVE PEAK WITHOUT A REDUCTIVE PEAK IN THE REVERSE SCAN DIRECTION AT
poly(A2P2CuC/GCE showed the irreversibility of the electrochemical oxidation of ASA at the
electrode. A better correlation coefficient for the dependence of peak current on the square root
of scan rate (R2=0.9983) than the scan rate (R2=0.9612) indicated that the oxidation of ASA at
poly(A2P2CuC)/GCE was predominantly diffusion mass transport controlled. Under optimized
PBS of pH 5.5, and square wave parameters, square wave oxidative peak current response of the
modified electrode showed linear dependence on the concentration in the range 1-200 µM of
associated %RSD values below 3.7% for (n=3) with a correlation coefficient (R2
), limit of
detection, and limit of quantification of 0.9986, 0.039 µM, and 0.13 µM, respectively. Recovery
was found in the range 96.5-100.5% with %RSD value of below 1.9% for (n=3), and interference
recovery in the range 97.2-103.4% in the presence of 50-200% of uric acid, ascorbic acid, and
glucose as potential interferents validated the applicability of the developed method for
determination of ASA content of tablet formulation. The aspirin level in the studied tablet was
ranged between 99.4 to 101.5% of their labeled values by the manufacturer with %RSD value of
below 2.6% confirming the efficiency of the method for ASA determination in real samples. The
present method had a better performance for determination of aspirin in tablet formulation as
compared with recently reported voltammetric methods, due to its requirement of simple
electrode modification step, provides the least limit of detection, and reasonably wider linear
dynamic range. |
en_US |