Direct Detection of Ofloxacin using MWCNT@Sm(OH)3Nanocomposite Modified Carbon Paste Electrode

One of the most important quinolones, Ofloxacin (OFX), was directly determined using a carbon paste electrode modified by MWCNT@Sm(OH)3nanocomposite using fast Fourier transform square wave voltammetry. The prepared electrode showed a considerable current increase compared to a bare one. The electrode surface was thoroughly characterized using field emission scanning electron microscopy and electrochemical impedance spectroscopy. The maximum performance efficiency of the developed electrode was reached at a scan rate of 0.1 V s?1, phosphate buffer pH 8 while the electrode contained 7% of Sm(OH)3nanoparticles and 5% of MWCNT in the entire paste. Based on the results, a wide linear range of response toward OFX concentration from 0.01 to 1.00 ?M was obtained (frequency of 700 Hz, number of cycles 8, and amplitude of 20 mV) and the limit of detection of 0.8 nM was achieved on top. The proposed electrode also successfully identified OFX in some pharmaceutical formula as well with adequate sensitivity and selectivity.