Copper-deficient cobalt ferrite nanoparticles were synthesized by a simple combustion method. In the synthesis, tests of different polyalcohols were carried out, demonstrating the effectiveness of glycerin as a cosolvent, facilitating the preparation of electrode modifier nanomaterials. A standing time (eight hours) before calcination causes a decrease in the secondary phase of hematite. In acidic conditions (pH 2.5), the limit of detection (LOD) was calculated as (99.4 nM), the limit of quantification (LQO) turned out to be (331 nM). and RSD 3.31%. The superior electrocatalytic activity of the copper-deficient cobalt ferrite modified electrode Co 0.87 Cu 0.13 Fe 2 O 4 /GCE correlates very well with its resistance R ct found by the EIS technique and which defined its electron transfer capacity. The detection limit obtained for Co 0.87 Cu 0.13 Fe 2 O 4 /GCE in the present study (99.4 nM) is lower than the other electrodes studied here. The results show the possibility of determining acetaminophen in complex biological matrices