Electrochemical aptasensing of human cardiac troponin I based on an array of gold nanodumbbells-Applied to early detection of myocardial infarction

Recently, convergence of nanotechnology, medicine, biology and chemistry has provided novel solutions for efficient diagnosis systems for disease markers. A detection method of troponin I (TnI), as the gold standard of acute myocardial infarction biomarker, was investigated and a novel aptasensor was presented for this biomarker. An array of gold nanodumbbells was firstly synthesized using putrescine as the shape directing agent at a surface. It was then applied as a transducer for the immobilization of a 76-mer TnI aptamer to fabricate a simple electrochemical TnI aptasensor. Using the aptasensor, TnI was detected in a linear range of 0.05–500 ng mL−1 with a limit of detection of 8.0 pg mL−1. The aptasensor showed a diagnostic sensitivity of 100% and a diagnostic specificity of 85% when challenged with blood serum samples of 89 individuals.