Troponins as Smart Biosensors for Point-of-care Detection of Acute Myocardial Infarction

Troponin molecules and their T, C and I subtypes have shown significance in early point-of-care assessment of acute myocardial infarction. Other slowly released proteins are Creatine kinase MB, Fatty acid-binding Protein and myoglobin. Conventional antibody-antigen immunoassays do measure these markers and need laboratory setting. So, these are not suitable for point of care. The magnetic particles in immunoassay enhance the utility of immunoassay due to their ability to facilitate the separation of the targeted compounds and their high sensitivity of analyte. The present report presents a innovative idea to explore the possibility of: 1. troponin subtypes by MALDI mass spectrometry technique; 2. developing sandwich magnetic immunoassay using solidphase Enzyme linked Immunosorbent Assay (ELISA) based on formation of “sandwich” complex of two different antibodies at two binding sites on same target troponin antigen. One antibody was attached with magnetic nanoparticles at on binding site and other antibody with fluorescent marker with glucose at other binding site. The concentration of troponinT in the blood sample was correlated with proportional concentration of glucose measured by glucometer. The application of nanotechnology in troponin analysis minimizes the artifacts of troponin analysis in AMI. Using site-specific agent such as a magnetic nanosphere is novel choice to estimate 1 pico gm/L. In addition, the magnetic nanoparticles enhance the analyte detectibility, sensitivity to analyte with optimal reaction speed. Furthermore, the nanospheres can be localized with use of external magnet. The technique provides simple point of care method. Furthermore, we proposed a simple technique of use of proteomics and magnetic nanoparticles to isolate and quantify AMI marker troponin in the blood sample wih use of glucometer. The MALDI mass spectrometry technique has potential of exploring more AMI sensitive Troponin or other proteins. The proposed magnetic immunoassay of point-of-care method shows potential as rapid reliable cost-effective efficient as cardiac protection device. The technique is simple, user-friendly and costeffective. The nanotechnology based glucometer may provide portable analyzer for quicker point-of-care testing at minimum cost.