REUSE OF SCREEN-PRINTED ELECTRODE FOR MODAFINIL DETECTION THROUGH A Cu-CYAMERULATE MODIFICATION

Modafinil is a stimulant drug used to treat excessive drowsiness and concentration [1,2]. Given its stimulating effects, some doping cases have been reported before and during competitions [2]. In detecting modafinil with an anti-doping character, a commercial screen-printed electrode was reused through a modification with Cu-cyamelurate (Cu-C). Using square wave voltammetry, a study was carried out on the proportion of Cu-C in water dispersion (1.25, 2.5 and 5.0 mg mL-1) and optimization of the voltammetric parameters (Estep (1 to 10 mV), amplitude (10 to 100 V) and frequency (1 to 100 Hz)). Cyclic voltammetry was used to compare the electroactive areas of different modified electrodes and speed influence (10 to 800 mV s-1). The highest current value was a determining factor for the proportion and parameter optimization tests. After establishing a concentration of 2.5 mg mL-1 of Cu-C in the dispersion, Estep = 5 mV, amplitude = 40 mV and frequency = 20 Hz were determined. The electroactive area resulted in an average of 0.469 cm2 and relative standard deviation of 3.75 %. The speed study showed Log I = 2.97(±0.02)-0.29(±0.02).logv indicating a process with a diffusional profile. Finally, the aim is to create an analytical curve in a saliva matrix and determine the respective limits of detection and quantification for modafinil, providing a method with good performance for possible application in doping control.