Later on, based on the same principle, the group achieved a LOD of 9.8 pg/mL of cTnI, which is considerably lower than the approved cTnI threshold for the diagnosis of cardiac diseases, by using core-shell nanotags and a magnetic separation based SERS immunoassay by employing 4-mercaptobenzoic acid as an active Raman reporter, thus achieving a diagnostic tool with advantages such as specificity, ultrasensitivity, reduced costs of fabrication, ease-of-use, and no sample pre-treatment with promising reliability and stability [39]. The gene discussed is TNNI3; the disease is heart disorder.