The portable stochastic sensor as a screening tool for simultaneous determination of HER-1 and CA 125 - a key factor in the rapid recognition of gastric cancer.

The significance of HER-1 and CA 125 lies in their ability to guide cancer diagnosis, treatment, and monitoring, improving personalized care and enhancing prognostic accuracy. The utilization of HER-1 and CA 125 as screening biomarkers for the anticipation of early-stage cancer and monitoring cancer progression is expanding due to the invasive and costly nature of present techniques. In this study, a novel stochastic sensor was developed for the simultaneous determination of HER-1 and CA 125 in whole blood, saliva, and gastric tumor tissue samples using a fast, easy, inexpensive, and portable method. The stochastic sensor was prepared by electropolymerization of cysteine on the surface of the Au-TiO ₂ @rGO/SPCE sensor. The Au-TiO ₂ @rGO nanocomposite was synthesized using a simple chemical reduction process. The proposed sensor showed wide linear concentration ranges and very low limits of quantification (LOQ). The concentration ranges were from 3.9 × 10 ^-14 to 3.9 × 10 ^-8  µg mL ^-1 , with a LOQ of 3.9 × 10 ^-14  µg mL ^-1 for HER-1. For CA 125, the concentration ranges were from 8.3 × 10 ^-14 to 8.3 × 10 ^-10 U mL ^-1 , with a LOQ of 8.3 × 10 ^-14 U mL ^-1 . Both biomarkers exhibit precise discrimination in different biological samples, with recoveries above 96.78% and RSD values below 0.04%. With a confidence level of 99%, the Student t-test revealed that there is no statistically significant difference between the outcomes obtained by using the poly-Cys/Au-TiO ₂ @rGO/SPCE sensor for screening examinations of biological samples. This was determined because the results were not significantly different from one another.
(© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)