NOVEL IMMUNOSENSOR USING CARBON FIBERS AND UTILIZING BIOMARKERS AS A STRATEGY TO DETECT DEFICIT OF TESTOSTERONE

Deficit of testosterone has been an increasing liability in the recurring years, including old and young males, as of a few studies, testosterone levels have been on decline. Sickness such as both types of hypogonadism have catched the interest in diagnostics recurring this similar problem. In this ongoing research, we have created a new type of sensor utilizing carbon fibers as the main work electrode wich has already been characterized in a previous study. The methodology as follows used a surface treament improving the electrochemical response, the second was the use of EDC/NHS coupling that would facilitate the immunoassay binding, as such, the final were using a conjugated antibody-antigen pair, the antigen being the testosterone. The electrochemical techniques performed were cyclic voltammetry and electrochemical impedance spectroscopy. Utilizing a redox solution containing ferri/ferrocyanide, the sensor was evaluated dropping an aliquot of testosterone in the ferri/ferro solution to reach a range of 0 to 500 ng/dL of testosterone for detection. Contrary to most responses, the testosterone increased the conductivity of the sensor. This was througly verified by the saturation time of the fiber and assessing it on different solutions. The ongoing step now is to find the characteristic circuit for the sensor in means of achieving the R_ct and the limits of detection and quantification (LOD & LOQ).

This work was supported by FAPESP (2024/08698-1) and CNPq (311368/2022-0).