Carbon dots based photoelectrochemical sensors for ultrasensitive detection of glutathione and its applications in probing of myocardial infarction.

In this work, photoelectrochemical (PEC) sensors based on carbon dots (CDs) were developed for ultrasensitive detection of glutathione (GSH) without additional catalysts. In this PEC sensing system, CDs exhibited both photoelectric and catalytic properties. Silver nanoparticles (AgNPs), graphene oxide (GO), and mesoporous silica (MS) were introduced in order to enhance the sensing properties of CDs for GSH. Among the different hybrid nanocomposites, CDs@MS based PEC sensors exhibited the best sensing properties: the sensitivity and limit of detection (LOD) for GSH were found to be 57.6nAμM- 1 and 6.2nM (S/N = 3), respectively, in the linear range 0.02-4μM. In addition, the developed PEC sensors showed a high selectivity for GSH even with interferences of other biological thiols and amino acids. The PEC sensor was successfully applied for GSH detection in human serum and probing of myocardial infarction (MI) conditions by estimating the amount of GSH in the myocardial cells of mice, which had been treated with different ischemia/ischemia-reperfusion times. These results indicated that the CDs based hybrid nanocomposites are promising candidates for the development of PEC biosensors with enhanced sensing performances.