In Vitro, Anti-Colon Cancer Activity of Green Dumbbell-Shaped Rhododendron luteum-Based Carbon Dots

Abstract

Colorectal cancer is the second most common cause of cancer-related deaths worldwide and the third most common cancer overall. In this study, we investigate the anti-colon cancer potential of phytochemically, and thermally synthesised novel green carbon dots based on Rhododendron luteum (RL-CDs). A new synthesis method was used to produce carbon dots obtained from the Rhododendron luteum (RL) plant in an environmentally friendly manner. The green RL were characterized using Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, transmission electron microscopy (TEM), and artificial intelligence (AI)-based TEM analysis. The FTIR spectrum showed peaks corresponding to the hydroxyl (−OH) vibration of polyphenols at 3500 cm⁻¹, the C=O vibration of cellulose derivatives at 1728 cm⁻¹, and the C−O stretching of primary alcohol at 1041 cm⁻¹. Two UV absorption peaks at roughly 253 nm (UV−C range), and 320 nm (UV−B range) were observed. The size of the green RL was measured to be less than 50 nm, and its morphology was characterized as dumbbell-shaped through TEM analysis. In-vitro studies were performed with HCT116 colon cancer, MCF-7 breast cancer, and normal HUVEC cells. The results demonstrated that the RL-CDs exhibited selective cytotoxic activity against HCT116 colon cancer cells. The results show that the RL extract stimulates cancer cell death by decreasing the CD44/24 ratio, and increasing apoptotic activity. These observations suggest that green RL-CDs could be an effective anticancer agent in colon cancer therapy, investigating their potential in this direction could be a promising way for future research.