Oxidative stress is caused by an imbalance between antioxidants and reactive oxygen and nitrogen species. It can lead to DNA damage and plays a critical role in the development and progression of cancer. Because of this, oxidative stress serves as an important biomarker for cancer detection and prognosis. It is also implicated in a variety of other pathologies, including increased viral severity, such as that observed in COVID‑19 infections. In this study, we aim to detect and quantify oxidative stress in cancer patients by measuring 8‑oxo‑2′‑deoxyguanosine (8‑oxo‑dG), a key biomarker of oxidative DNA damage. We are developing a DNA‑aptamer–based, gold‑nanoparticle colorimetric assay to quantify 8‑oxo‑dG in saliva samples. The outcomes of this work will advance the assessment of oxidative stress levels and strengthen investigations into potential correlations between oxidative stress, cancer development, and patient prognosis.
