Preparation of aldehyde-graphene quantum dots from glucose for controlled release of anticancer drug

Abstract

In this study, we prepared graphene quantum dots (GQDs) via a green process using rice straw as a carbon source. The non-toxic nature of GQDs is suitable for application in human body-related research. Furthermore, GQDs possess biodegradability and biocompatibility characteristics, indicating high suitability for applications in the field of drug delivery. Based on the fact that acid-sensitive bonds between GQDs and the drug doxorubicin are formed by aldehyde groups on GQD surfaces, we adopted a semi-modified TEMPO method to partially oxidize the surface functional groups of GQDs without destroying the structure. This enabled an increase in the surface aldehyde group content, which in turn enhanced the drug loading capacity of GQDs. The aldehyde group content of the GQDs was measured via Fourier transform infrared (FTIR) spectroscopy, titration based on the Cannizzaro reaction, and X-ray photoelectron spectroscopy (XPS). The drug loading effect of the GQDs was determined via absorbance measurements at 485 nm on a UV-Vis spectrophotometer. The results indicated that the semi-modified TEMPO method significantly affected the introduction of surface aldehyde groups and the enhancement of the drug loading efficiency in GQDs. Finally, the polymeric material cationic poly (vinylcyclohexene carbonates) (CPVCHCs) was used for the encapsulation of GQDs and regulation of drug release. Under the premise that the total amount of drugs released remains unaffected, the initial burst release of the drug is effectively delayed, which aids in reducing harmful effects of the drug on the human body.

A review on synthesis, properties, and biomedical applications of graphene quantum dots (GQDs)

“…The bottom-up method involves synthesizing GQDs from various small organic molecules such as glucose, citric acid, or higher polymers like starch and chitosan [61][62][63][64][65]. One of its advantages is the ability to synthesize GQDs with excellent crystallinity and a relatively uniform size distribution compared to the top-down approach.…”

Synthetic applications of the Cannizzaro reaction

“…Moreover, enzymatic transformations have been also observed for the synthesis of α-hydroxycarboxylic acids [ 47 ]. They are also used in the development of different nanoparticle preparations and other reactions for synthesis of bioactive compounds [ 48 – 50 ].…”

Recent advances in biomedical applications of carbon and graphene quantum dots: A review

“…The studies indicated the accumulation of the conjugate in cancer cells and enhancement of signal spectrum to almost double of that obtained with the GQDs only(Lin et al, 2022).Shi et al prepared GQDs and increased the aldehyde groups on their surfaces by partial oxidation to enhance the drug loading capacity of the anticancer drug doxorubicin. The drug-loaded GQDs were encapsulated by the polymers of vinylcyclohexene carbonates to regulate the drug release and were reported to be pH sensitive(Shi et al, 2023). Xia et al devised a strategy for the treatment of solid tumors by grafting GQD-linked micro RNA miR155 on to the surface of monocytes through an 18 carbon-containing alkene with a short peptide.…”