A facile and sensitive method of analysis for the determination of paracetamol on a boron doped diamond electrode modified with carbon based nanomaterials

This study presents the development of a facile and sensitive method of analysis for the determination of paracetamol. For this purpose, a boron doped diamond electrode (BDDE) was modified with a composite of carbon nanotubes (CNT), carbon nanofibers (CNF) and carbon black nanoballs (CNB). The voltammetric properties of paracetamol were studied, compared and discussed on unmodified BDDE, CNB/BDDE, CNF/BDDE, CNT/BDDE, CNB@CNF/BDDE, CNF@CNT/BDDE and CNF@CNB@CNT/BDDE. An increase in peak response (Ip) and a dramatic decrease in peak separation (ΔEp) were observed at electrodes in an order from bare BDDE to CNB/BDDE, CNF/BDDE, CNT/BDDE, CNB@CNF/BDDE, CNF@CNT/BDDE and CNF@CNB@CNT/BDDE. This clearly showed that the composite material of CNF@CNB@CNT provided an excellent surface on BDDE leading to a fast electrode reaction of paracetamol. Interestlingly, the amount composite layer on the voltammetry of paracetamol also caused a remarkable decrease in ΔEp and resulted in high electrocatalytic activity. The detection of paracetamol based on the BDDE modified with a composite of CNF@CNB@CNT exhibited stability, excellent selectivity and good sensitivity, with a low detection limit of 0.47±0.002 nM (based on 3s_b/m) and wide linear range of 1.5 nM–200 nM. These results demonstrate that CNF@CNB@CNT/BDDE can serve as an ideal voltammetric platform for constructing a paracetamol sensor. The proposed electrochemical platform (CNF@CNB@CNT/BDDE) was also successfully applied for the determination of paracetamol in pharmaceuticals and body fluids.