Early detection of cancer: Focus on antibody coated metal and magnetic nanoparticle-based biosensors

Abstract

Cancer is a highly fatal disease, and due to contemporary lifestyle and growing, environmental pollution chances of cancer are increasing, which is a global threat. The high mortality rate in cancer is caused primarily due to its late detection, mostly in a metastatic third or fourth stage, resulting in a poor after therapy prognosis. The conventional detection methods include identification of carcinogenic features of cells such as DNA or RNA mutation, conformational changes and overexpression of some proteins, and cell morphology, which are called biomarkers or analytes. Those processes are specialist-dependent, time-consuming, and expensive. Recently, biosensors are becoming popular as easy, quick, cheap, and highly sensitive detection tools. The biosensor technique depends on the availability of biomarkers in the sample. Thus, identifying new molecular markers for various types of cancers is a parallel issue, which is, fortunately, in rapid progress. A biosensor has a biomarker-specific layer of biorecognition elements on a transducer, which acts as an electrode. Upon binding of biomarkers with the biorecognition elements, a chemical signal gets generated. The transducer converts that signal into a measurable output for further analysis. Among several biorecognition elements, antibodies (Abs) are highly demanding, especially for the cancer diagnosis, for their unique three-dimensional structures and high specificity. However, the conventional biosensors produce inaccurate results at the low concentration of biomarkers in the patient's sample in an early stage of cancer. The use of nanoparticles shows remarkable improvement in the sensitivity of biosensors. This article has reviewed recent applications of nanoparticles in biosensor development and made a recommendation based on safety, cost and convenience.