Coordination‐Driven Metal‐Polyphenolic Nanoparticles toward Effective Anticancer Therapy

Stabilization of bioactive components, especially for hydrophobic functional factors, is a promising approach for improving their biological activity. Here, a metal-phenolic coordination chemistry that synthesizes biocompatible and biodegradable thin film based on tannic acid and trivalent metal ion (Fe³⁺ or Al³⁺ ) is addressed, and the results also demonstrate its use for encapsulating a hydrophobic drug (nobiletin) and triggering drug release for cancer treatment both in vitro and in vivo. This assembled system provides drug-loaded nanoparticles (NPs) with small, but uniform, size (≈200 nm). It displays beneficial potential in enhancing colloidal stability and preventing premature drug leakage. Moreover, the metal-phenolic coating is found to possess high cell biocompatibility as a delivery vector for controlled drug delivery, while the final fabricated drug NPs have effective anti-tumor activity by both inducing higher tumor apoptosis and inhibiting tumor metastasis, which is superior to naked drug formulations. Overall, these findings propose an effective and straightforward way for coating hydrophobic drugs employing interfacial adhesion and assembly, which can be a highly promising vehicle for controlled-release biomedical applications for cancer therapy.