Construction of an aptasensor based on the composite nanomaterial IL-rGO-TEPA/SiO2-AuPt and its high-sensitive detection of cardiac troponin I

To accurately diagnose and evaluate the degree of myocardial injury and predict myocardial infarction disease, the rapid and sensitive detection of cardiac troponin I (cTnI) is required. Therefore, a label-less electrochemical aptasensor was prepared for cTnI determination. Ionic liquid 1-hydroxyethy l-3- methyl imidazole four fluorine boric acid salt (IL)-reduced graphene oxide − four ethylene oxidation reduction five amine (rGO-TEPA)/silica (SiO₂)- gold platinum (AuPt) (IL-rGO-TEPA/SiO₂-AuPt) nanocomposites were synthetized as the substrate nanocomposite and were characterized using a series of characterization methods. The performance of the prepared aptasensor was characterized through electrochemical methods. Result displayed that better substrate materials were synthesized, and the prepared electrochemical aptasensor showed excellent electrochemical performance. Under optimal conditions, the electrochemical aptasensor had a salient analytical performance. The electrochemical signals linearly decreased with the logarithm of the cTnI concentration between the 0.5 pg·mL⁻¹ and 1 × 10⁶ pg·mL⁻¹ concentration range (R² value = 0.9955) and the aptasensor had a wide detection range (0.5 ∼ 1 × 10⁶ pg·mL⁻¹) and a low detection limit of 0.4 pg·mL⁻¹. At the same time, the aptasensor had good selectivity, repeatability and stability. Relative standard deviation (RSD) values ranged from 3.45 % ∼ 4.97 % and the recovery rate was 97.5 % ∼ 103 % in human serum samples, the RSD values of the spiked recovery and ELISA method were less than 5 %. This study provides a new theoretical basis and method for the clinical detection of cTnI.