Paper-based Immunosensor for Oxidative DNA Damage Biomarker Detection

Oxidative stress is an abnormal oxidant system which can be caused by many toxicants exposure. In the presence of oxidative stress, reactive oxygen species generated in vivo can directly cause oxidative damage to lipids, proteins and DNA. In DNA, 8-hydroxy-2´-deoxyguanosine (8-OHdG) is one of the predominant forms of free radical-induced oxidative lesions, and therefore has been widely used as a biomarker for oxidative stress and carcinogenesis. Studies showed that urinary 8-OHdG is a good biomarker for risk assessment of various cancers and degenerative diseases. Urinary 8-OHdG has been measured by many methods, but most of them are usually time-consuming, require specialized lab based equipment, dedicated sample preparation process and professional operators. There is great need for a portable sensing system capable of rapid 8-OHdG measurement in readily available biosamples. Here we develop an immunochromatographic paper strip capable of quantitative analysis of 8-OHdG in samples. The test strip will provide a point of care testing method for quantitative assessment of DNA oxidative stress with high sensitivity, specificity, speed of performance and the advantages of simplicity.