Detection of disease at an early stage is one of the biggest challenges in medicine. Different disciplines of science are working together in this regard. The goal of nanodiagnostics is to provide more accurate tools for earlier diagnosis, to reduce cost and to simplify healthcare delivery of effective and personalized medicine, especially with regard to chronic diseases (e.g., diabetes and cardiovascular diseases) that have high healthcare costs. Up-to-date results suggest that DNA-based nanobiosensors could be used effectively to provide simple, fast, cost-effective, sensitive and specific detection of some genetic, cancer, and infectious diseases. In addition, they could potentially be used as a platform to detect immunodeficiency, and neurological and other diseases. This review examines different types of DNA-based nanobiosensors, the basic principles upon which they are based and their advantages and potential in diagnosis of acute and chronic diseases. We discuss recent trends and applications of new strategies for DNA-based nanobiosensors, and emphasize the challenges in translating basic research to the clinical laboratory.

Sol-gel derived nanostructured cerium oxide $\left(\mathrm{Ce}{\mathrm{O}}_2\right)$ film deposited on gold (Au) electrode has been utilized for physisorption of glucose oxidase (GOx). X-ray diffraction, atomic force microscopy, UV-visible spectroscopy, and electrochemical techniques have been used to characterize sol-gel derived $\mathrm{Ce}{\mathrm{O}}_2∕\mathrm{Au}$ electrode and $\mathrm{G}\mathrm{O}\mathrm{x}∕\mathrm{Ce}{\mathrm{O}}_2∕\mathrm{Au}$ bioelectrode. The response characteristics of the glucose bioelectrode $(\mathrm{G}\mathrm{O}\mathrm{x}∕\mathrm{Ce}{\mathrm{O}}_2∕\mathrm{Au})$ indicate linearity, detection limit and shelf-life as $50–400\mathrm{mg}∕\mathrm{dL}$ , $12.0\mu \mathrm{M}$ , and $12\text{weeks}$ , respectively. The value of apparent Michaelis–Menten constant $\left(K_m\right)$ of $\mathrm{G}\mathrm{O}\mathrm{x}∕\mathrm{Ce}{\mathrm{O}}_2∕\mathrm{Au}$ bioelectrode has been found to be $13.55\mu \mathrm{M}$ .