Non-enzymatic Detection of Cardiac Troponin-I with Graphene Oxide quenched Fluorescent Iron Nanoclusters (FeNCs).

Cardiac troponin I (cTnI) is the most resorted biomarker for the detection of cardiovascular disease (CVD). The means of rapid quantification of cTnI levels in the blood can substantially minimize the risk of acute myocardial infarction and heart failure. A sensor for the non-enzymatic evaluation of cardiac troponin-I has been developed using fluorescent iron nanoclusters via a one-pot synthesis employing (BSA) as the template and reducing agent, and hydrogen peroxide as the additive. The fluorescence of Iron Nanocluster is quenched with graphene oxide (GO) via fluorescence resonance energy transfer (FRET) between conjugate iron nanoclusters and graphene oxide. The sensor shows a low detection limit of 0.013 ng/mL. The benefits of utilizing a non-enzymatic probe for detecting cardiac troponin I is that it avoids the need for enzymes and hence is economical, stable, and less impacted by environmental conditions such as temperature and pH. Non-enzymatic probes are more useful for clinical use since they are more stable and have a longer shelf life. The developed non-enzymatic probes are also highly selective and sensitive to the target analyte, making them suitable for the direct detection of cardiac troponin I in actual biological samples.

Mo(IV) Ion-Modulated BSA-Protected Gold Nanocluster Probe for Fluorescence Turn-On Detection of Trimethylamine N-Oxide (TMAO).

Trimethylamine N-oxide (TMAO), a molecule produced by the microbiota, has been associated with human health and illness. Its early discovery in body fluids may affect our understanding of the pathophysiology and treatment of many illnesses. Therefore, our knowledge of the pathophysiology and diagnostics of disorders associated with TMAO might be enhanced by the creation of dependable and fast methods for TMAO detection. Therefore, we developed a fluorescent probe for detecting TMAO utilizing an on-off-on strategy. Bovine serum albumin (BSA)@AuNCs luminescence is effectively quenched by Mo4+ because BSA@AuNCs and Mo4+ have a strong binding relationship. Mo4+ ions can substantially decrease the emission intensity of gold nanoclusters by establishing a BSA@AuNCs-Mo system. Then, the luminescence of BSA@AuNCs was restored due to the interaction between Mo4+ and TMAO. A significant linear relationship was seen between the emission intensity and TMAO concentration within the 0-201 µM range, with a detection limit of 1.532 µM. Additionally, the method can measure TMAO in blood and urine samples.