Experimental and Theoretical Investigation of the Electronic Structure of 5-Fluorouracil Compounds

Computational screening of metalloporphyrin-based drug carriers for antitumor drug 5-fluorouracil

Developing novel nanoscale carriers for drug delivery is of great significance for improving treatment efficiency and reducing side effects of antitumor drugs. In view of the good biocompatibility and special affinity of porphyrin (PP) molecule to cancer cells, it was used to construct a series of metal-doped M@PP (M = Ca ∼ Zn) materials for the delivery of anticancer drug 5-fluorouracil (5-Fu) in this work. Our results reveal that 5-Fu is tightly adsorbed on M@PP (M = Ca ∼ V, Mn ∼ Co, and Zn) by chemisorption, but is physically adsorbed by M@PP (M = Cr, Ni, and Cu). The calculated electronic properties show that all these 5-Fu@[M@PP] (M = Ca ∼ Zn) complexes have both high stability and solubility. Among these 5-Fu@[M@PP] complexes, the chemical bond formed between 5-Fu and Ti@PP has the strongest covalent characteristic, resulting in the largest adsorption energy of -19.93 kcal/mol for 5-Fu@[Ti@PP]. In particular, 5-Fu@[Ti@PP] has the proper recovery time under the near-infrared light at body temperature, which further suggests that Ti@PP is the best drug carrier for 5-Fu. This study not only reveals the interaction strength and nature between 5-Fu and M@PP, but also confirmed the intriguing potential of Ti@PP as nano-carrier for drug delivery. However, further experimental research should be conducted to verify the conclusion obtained in this work.

DFT study on the adsorption of 5-fluorouracil on B40, B39M, and M@B40 (M = Mg, Al, Si, Mn, Cu, Zn)

Based on density functional theory, the adsorption behavior of 5-fluorouracil (5-Fu) on B₄₀ and its derivatives has been explored. It was observed that 5-Fu prefers to combine with the corner boron atom of the B₄₀ cage via one of its oxygen atoms, forming a strong polar covalent B–O bond. The adsorption energy of 5-Fu on B₄₀ was calculated to be −11.15 kcal mol⁻¹, and thus, it can be duly released from B₄₀ by protonation in the slightly acidic environment of tumor tissue, which makes for reducing the toxic and side effects of this drug. Additionally, the substituent and embedding effect of Mg, Al, Si, Mn, Cu, and Zn atoms on the drug delivery performance of B₄₀ have been also considered. We hope this work could offer some implications for the potential application of boron-based nanomaterials, such as B₄₀ in drug delivery.

The adsorption of 5-fluorouracil on B₄₀ and its derivatives has been theoretically studied to provide some implications for the potential application of B₄₀ in drug delivery.