Design and fabrication of electrochemical biosensors for early diagnosis of myocardial infarction and Hepatocellular Carcinoma using microRNAs (miRNAs) primers as biorecognition element and arrays of gold nanostructures

Abstract

Since cardiovascular disease is the leading cause of death in the world (over 30% of all deaths annually), finding a way to predict cardiovascular disease quickly is one of the most critical challenges; Myocardial Infarction (MI) is the most important heart disease. On the other hand, unfortunately, liver cancer is the third deadliest cancer in the world. Hepatocellular Carcinoma (HCC) is a type of cancer and the most common primary malignant tumor of the liver. Early diagnosis is highly effective in the possibility of success in treatment. Access to portable, low-cost, high-sensitive diagnostic tools for the diagnosis of Myocardial Infarction and Hepatocellular Carcinoma is highly desirable. Biosensors are tools that can be designed and fabricated at a lower cost and can also detect the analytes with high sensitivity and selectivity in a short time. In this research, we will design and fabricate two electrochemical biosensors for early diagnosis of MI and HCC using microRNAs (miRNAs) primers as biorecognition element and several arrays of gold nanostructures. In the biosensors that will be designed in this study, short primer sequences (aptamers) are used as the biorecognition element against the analytes (miRNAs). Ideally, aptamers have a high affinity (low detection limit), high selectivity (minimum interference), wide dynamic range, and short response time. The increased expression of miRNA-133a with the sequence of 5'-AGCUGGUAAAAUGGAACCAAAU-3' as a diagnostic biomarker has been found and confirmed after MI. On the other hand, miRNA-1972 as a novel diagnostic biomarker with the sequence of 5'-UCAGGCCAGGCACAGUGGCUCA-3' will be evaluated to the diagnosis HCC. The expression of miRNA-1972 is increased in HCC patients. (AU)