Sustainable Carbon Dots Loaded into Carboxymethylcellulose Based Hydrogels for Uterine Cancer Bioimaging

Background/Objectives: The development of innovative materials for disease diagnostics and therapeutics is a fast-growing area of scientific research. In this work, we report the development of innovative hydrogels incorporating carbon dots (Cdots) for bioimaging purposes. Methods: The Cdots were prepared using a sustainable and low-cost process, starting with an underused fiber from the Brazilian semiarid region. Spectroscopy analysis (Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, UV-visible spectroscopy), X-ray diffraction, photoluminescence, zeta potential, scanning electron microscopy, and transmission electron microscopy were used to characterize these hydrogels. In addition, biocompatibility using the resazurin assay and cellular uptake by confocal microscopy were evaluated. Results: Our results showed that the Cdots changed the structure and crystallinity of hydrogels, mainly due to heat treatment. In addition, hydrogels' chemical groups suffer red and blue shifts following the Cdots incorporation. Moreover, the Cdots were homogeneously incorporated into the hydrogel matrix. Importantly, the cytotoxicity levels were maintained above 90% (p < 0.01), and cellular uptake studies using HeLa cells demonstrated intracellular fluorescence of both the Cdots and hydrogels after incubation. Additionally, the concentration of Cdots within hydrogels significantly affected fluorescence intensity, even compared with pure Cdots. Conclusions: These results showcase the potential for these hydrogels to be further developed as biomarkers and therapeutic biomaterials for women's health.