Preparation of Carbon Dots From Geranium carolinianum L. and Their Protective Effect on Myocardial Ischemia Injury in Rats

Graphical Hydrothermally-synthesized GCL-derived carbon dots (2.8nm) exhibited potent antioxidant activity, scavenging DPPH/ABTS radicals and protecting H9c2 cells from H₂O₂ damage. In ISO-induced AMII rats, GCL-CDs reduced ECG S-T elevation, infarct size, and cardiomyocyte apoptosis while promoting tissue repair, likely via oxidative stress alleviation, demonstrating myocardial protection. In this paper, a type of carbon dots (CDs) was prepared at 220°C for 8 h by a hydrothermal method using Geranium carolinianum L. (GCL) as the carbon source. GCL CDs were spherical in shape with the particle size of 2.8 ± 0.6 nm. In vitro studies showed that GCL CDs had a good scavenging activity against the free radicals of DPPH and ABTS, and had a good protective effect against H 2 O 2 -induced oxidative damage of H9c2 cells, suggesting that GCL CDs have good antioxidant activity. In vivo studies showed that GCL CDs had a good protective effect on isoprenaline (ISO)-induced acute myocardial ischemic injury (AMII) in rats, which was reflected by their ability to significantly reduce the S-T band of the electrocardiogram, markedly reduce the infarcted area of AMII, effectively and rapidly restore the damaged cardiomyocytes, and significantly reduce the apoptosis of the cardiomyocytes, which prevented further damage to the cardiomyocytes. The comprehensive results of the above experiments indicate that the protective mechanism of GCL CDs against AMII is probably through the elimination of oxidative stress in the body, so that the damaged cardiomyocytes can be restored, so as to play a protective effect on AMII.