Quantitative evaluation of oxidative stress in terms of H2O2 in smokers and nonsmokers serum samples

[Display omitted] •Reactive oxygen species are formed during enzymatic and non-enzymatic reactions in biological systems.•Bimetallic Fe-Ni affixed electrode found to exhibit tremendous electrocatalytic capability toward H2O2 stress.•The proposed method worked well in real samples (human blood serum) The bimetallic Fe-Ni nanomaterial was synthesized by a modified co-precipitation method and characterized by various techniques. The results showed random morphology with a face-centered cubic structure with an average diameter of 60 nm. The cyclic voltammetry and amperometric techniques were used to analyze the oxidative stress caused by hydrogen peroxide. Different parameters were optimized including scan rate, pH, and concentration. The material showed promising performance in phosphate buffer of pH 7.2 for standard and serum with correlation coefficients of 0.9897 and 0.99054, respectively. The detection limit for hydrogen peroxide was 5.9 µM and 7.3 µM (n = 3) for standard and serum, respectively. Fe-Ni@GCE is selective towards hydrogen peroxide in the presence of interferences. The modified electrode is stable up to 50 hrs with a loss of 25% performance. The developed sensor is applied to evaluate the percentage recovery from human blood serum samples of smokers and non-smokers. A quantitative study is also performed using serum samples of smokers and nonsmokers. The results showed a positive association and higher H2O2 in smokers compared to nonsmokers. Smoking may be a critical factor in oxidative stress in smokers older than 30 years related to smoking compared to non-smokers of the same age group. It is expected that bimetallic Fe-Ni nanomaterial can be exploited to detect specific levels of hydrogen peroxide as biomarkers and monitor disease severity.