Background: Tuberculosis (TB) is a life-threatening human disease and ESAT-6 protein in
TB is vital for the effective diagnosis, treatment, disease prevention and control. ESAT-6 is an early secretory
protein by the pathogen (Mycobacterium tuberculosis), a suitable candidate to detect TB at an
Methods: Enzyme-linked immunosorbent assay (ELISA) is the standard assay used to detect pathogens
with higher sensitivity. Since Gold nanoparticle (GNP) is a sensitivity improvement material in biosensor,
in this study, we proposed ELISA combined GNP to detect the low abundance of ESAT-6.
Results: GNP-assisted ELISA exhibited ~7.5-fold improved detection compared to the conventional
ELISA. Larger (80 nm) sized GNP provided a higher sensitivity than smaller (10 nm) sized GNP. The
detection limit of this method has attained the level of 1 nM of ESAT-6.
Conclusion: This method can be used to detect the presence of ESAT-6 and provides a model for sensitive
detection of other pathogens such as HIV and Influenza.