Supramolecular assembly of pentamidine and polymeric cyclodextrin bimetallic core–shell nanoarchitectures

Abstract

Advanced nanoscale antimicrobials, originated from the combination of noble metal nanoparticles (NPs) with conventional antimicrobial drugs, are considered the next generation of antimicrobial agents. Therefore, there is an increasing demand for rapid, eco-friendly, and relatively inexpensive synthetic approaches for the preparation of nontoxic metallic nanostructures endowed with unique physicochemical properties. Recently, we have proposed a straightforward synthetic strategy that exploits the properties of polymeric β-cyclodextrin (PolyCD) to act as both the reducing and stabilizing agent to produce monodispersed and stable gold-based NPs either as monometallic (nanoG) structures or core–shell bimetallic (nanoGS) architectures with an external silver layer. Here, we describe the preparation of a supramolecular assembly between nanoGS and pentamidine, an antileishmanial drug endowed with a wide range of therapeutic properties (i.e., antimicrobial, anti-inflammatory, and anticancer). The physicochemical characterization of the supramolecular assembly (nanoGSP) in terms of size and colloidal stability was investigated by complementary spectroscopic techniques, such as UV–vis, ζ-potential, and dynamic light scattering (DLS). Furthermore, the role of PolyCD during the reduction/stabilization of metal NPs was investigated for the first time by NMR spectroscopy.

A Supramolecular Assembly of EGCG for Long-Term Treatment of Allergic Rhinitis

“…To address these issues, we synthesized nanosized polycyclodextrin (PCD) as carriers for EGCG loading in this paper. Unlike the water-soluble CD inclusion complexes, PCD are are hydrophilic nanoparticles under 200 nm formed by cross-linked CD, which are beneficial in controlling the release of drug and improving the bioavailablility in vivo due to the small size and surface effects. − In addition, thiolated chitosan (TCS) was selected as component blending with PCD@EGCG complexes to extend the retention time of system in nasal mucosa, since TCS has better water solubility than chitosan, which allows better mixing with PCD@EGCG nanoparticles, and the sulfhydryl groups of TCS can covalently bond with the cysteine residues of mucins on mucosal surface to form disulfide bonds and then enhance the mucosal adhesion of nanocarriers. − …”