Cysteine monolayer has been assembled onto
bare gold electrode (SAM/Au), and subsequently deoxyribonucleic acid (DNA) has been successfully immobilized at the SAM/Au electrode. The thus modified
electrode is assigned DNA/SAM/Au. Modification steps
of the electrode were followed electrochemically using
K4[Fe(CN6)] electrochemical marker. Also, the build-up
of the modified electrode composition is followed using
EDX and the crystallographic orientation is inspected
using XRD. The electrochemical behavior of paracetamol
(PC) at DNA/SAM/Au electrode is investigated. Interestingly, the sluggish irreversible behavior of PC at the bare
gold electrode is converted to a quasi-reversible one at
DNA/SAM/Au electrode pointing to some interaction
between the immobilized DNA and PC. The enhanced
electrochemical behavior of PC at modified DNA/SAM/
Au electrode is successfully used for a sensitive electrochemical determination of PC. Square wave voltammetry
(SWV) was used for this purpose. The concentration of
PC was in linear relation with the peak current at the
optimum conditions within the range 10.0–110.0 μg mL 1
with correlation coefficient (R2) of 0.998. Also, the
standard deviation (SD) and relative standard deviation
(RSD) were calculated and found to be 0.817 and 1.52,
respectively, indicating the significance of the present
method.