Tailored Surface Functionalization of AlN Nanotubes for 5-Fluorouracil Adsorption and Encapsulation: A First-Principles and Molecular Dynamics Study

Abstract

The rational design of biocompatible nanocarriers is essential for improving the efficacy and safety of anticancer therapeutics. Aluminum nitride nanotubes (AlNNTs) functionalized with biologically relevant sorbic acid (SA), butyric acid (BA), amine (–NH₂), and carbonyl (C=O) groups are evaluated as potential delivery platforms for 5-fluorouracil (5-FU). Surface modification with these functional groups enhances the polarity, active-site reactivity, and aqueous dispersibility of AlNNTs, generating a chemically enriched interface for strong drug anchoring. Structural analysis reveals pronounced local rehybridization, increased dipole moments, and improved solvation tendencies upon functionalization. The modified systems exhibit stronger adsorption energies and enhanced charge redistribution, confirming favourable interactions and encapsulation behaviour toward 5-FU. Furthermore, the calculated activation energy barriers indicate stable drug retention under physiological conditions with the possibility of stimulus-responsive release at the therapeutic site. Collectively, these findings position dual-functionalized AlNNTs as promising and tunable nanocarriers, laying a predictive foundation for the rational design of one-dimensional platforms for precision-targeted anticancer drug delivery.