Preparation of amylose-poly(methyl methacrylate) inclusion complex as a smart nanocarrier with switchable surface hydrophilicity.

Amylose, as a linear biopolymer, tends to form helical inclusion complexes with suitable guest species. This is of great importance for a variety of applications, especially in the pharmaceutical and food industry. In this study, we propose an approach for the preparation of a novel inclusion complex with switchable surface hydrophilicity. For this purpose, amylose was first conjugated to ethylene diamine hydrophilic residues. Then, the short chains of the hydrophobic poly(methyl methacrylate, PMMA) were grafted onto the cavity of amylose through atom transfer radical polymerization (ATRP). According to CD spectroscopy results, the amylose-PMMA inclusion complexes displayed solvent-directed helical chirality inversion using either DMSO or water as a solvent. Fluorescence imaging, AFM and DLS techniques revealed the solvent-dependent surface hydrophilicity of the amylose-PMMA inclusion complex. Interestingly, its morphological studies displayed a central cavity, which makes it suitable for carrying cargoes in drug delivery applications. Obtaining the amylose-polymer inclusion complexes with tailorable hydrophilicity of both the exterior surface and the interior cavity can be of paramount importance for a wide variety of bio-applications.