Development of novel self-assembled poly(3-acrylamidophenylboronic acid)/poly(2-lactobionamidoethyl methacrylate) hybrid nanoparticles for improving nasal adsorption of insulinElectronic supplementary information (ESI) available: The preparation of LAMA, CPADB, APBA, DMP, FITC-labeled insulin; IR spectra of pLAMA and pAPBA; Thermal analysis of pAPBA/pLAMA NPs and the solid mixture of pAPBA and pLAMA. See DOI: 10.1039/c1sm06085f

It is well-known that the phenylboronic acid derivatives have chemical interactions with sugars. Hence, stable nanoparticles with core-shell structure were formed by the covalent complexation between boronic acid groups of poly(3-acrylamidophenylboronic acid) (pAPBA) and hydroxyl groups of poly(2-lactobionamidoethyl methacrylate) (pLAMA). The image taken by transmission electron microscopy (TEM) shows that the nanoparticles had a size of about 200 nm and were irregular spheres. The methyl thiazolyl tetrazolium (MTT) assay suggests that the nanoparticles were non-cytotoxic on the human colorectal carcinoma (Caco-2) cells. The confocal laser scanning microscope (CLSM) images show that the nanoparticles could internalize into Caco-2 cells. The insulin-loaded nanoparticles by intranasal administration led to a significant decrease in the plasma glucose levels and the histological assessment revealed that the nanoparticles would not develop lesions in the nasal epithelium. The nanoparticles are promising carriers for peptide and protein drugs in nasal delivery. Novel pLAMA/pAPBA hydrid NPs were prepared by the interaction between phenylboronic acid and lactose groups. The NPs had a continuous insulin release for decreasing the plasma glucose level in rats.