摘要
This work describes the preparation of an amperometric sensor for electrocatalytical detection of l-cysteine (Cys). The developed sensor is based on a functional platform to complex copper ions on multi-walled carbon nanotubes (MWCNTs) modified with poly-4-vinylpyridine (PVP) through an in situ polymerization. The obtained values for the kinetic constants of heterogeneous electron transfer rate (ks) and for chemical reaction (kobs) between Cu2+ and cysteine were 5.78 s鈭? and 6.96 L mol鈭? s鈭?, respectively. The analytical curve showed a linear response range for detecting l-cysteine in concentrations from 5 to 60 渭mol L鈭?. The detection and quantification limits obtained were 1.50 and 5.00 渭mol L鈭?, respectively with a response time of 0.10 s at an applied potential of 150 mV vs SCE.