Development of an electrochemical sensor for the determination of glycerol based on glassy carbon electrodes modified with a copper oxide nanoparticles/multiwalled carbon nanotubes/pectin composite

•An electrochemical sensor to determine glycerol in biodiesel was developed.•The platform is based on copper oxide nanoparticles supported on MWCNT/GC electrode.•Copper oxide nanoparticles promote the electrochemical oxidation of glycerol.•The sensor exhibits good performance and statistical parameters. A very sensitive electrochemical sensor to determine glycerol (GLY) in biodiesel samples has been developed. It is based on the electrochemical oxidation of GLY at glassy carbon electrodes modified with copper oxide nanoparticles supported on multiwalled carbon nanotubes/pectin composite. The electrochemical oxidation of GLY was studied in pH 8 phosphate buffer solutions. The quantification of GLY was performed by amperometric measurements. The proposed electrochemical sensor improves the performance of others methods developed for the quantitation of GLY. A low limit of detection of 5.8×10−6g dm−3 and a percent coefficient of variation smaller than 10% was found, along with a reasonable linear range of 9×10−6–1×10−3g dm−3. The proposed electrochemical sensor exhibited good performance, stability, reproducibility, repetitiveness and a good detection limit and a linear concentration range to quantify GLY in biodiesel samples.