Electrochemical DNA Biosensor for Mycobacterium leprae Identification

ABSTRACT

Abstract Nowadays, a prompt and reliable diagnosis is one of the most critical measures for leprosy control. The current diagnostic is based on clinical exams by a health care professional, and it may not recognize early signs of the disease. Therefore, other leprosy diagnosis methods are needed that are sensitive, disease-specific, and easy to deliver to the end-user. This study describes the construction of an electrochemical DNA biosensor to detect PCR products of Mycobacterium leprae using methylene blue as an indicator of the hybridization. The capture probe was immobilized on the graphite electrode modified with poly(4-aminophenol). The electrode surface was morphologically characterized by atomic force microscopy. Linear voltammetry was used to monitor the concentration of methylene blue on the DNA biosensor, which indicated a limit detection of 1 x 10-10 mol/L. The biosensor showed selective when placed to hybridize with a non-complementary sequence. This study suggests that the electrochemical DNA biosensor developed is promising for detecting DNA of Mycobacterium leprae.