Synthesis, Characterization of Biomimetic Phosphorylcholine-Bound Chitosan Derivative and In Vitro Drug Release of Their Nanoparticles

Novel water-soluble biomimetic phosphorylcholine (PC)-bound chitosan derivatives (N-PCCs) with different degree of substitution (DS) via a phosphoramide linkage between glucosamine and PC were synthesized through Atherton-Todd reaction under the mild conditions, and structurally characterized by H-1-NMR, Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Their DS ranged from similar to 16 to similar to 42 mol % based on the H-1-NMR spectra. All these N-PCCs with decreased crystallization showed excellent solubility in the aqueous solutions within a wide pH range (1-12). DSC and TGA results revealed that the thermal stability of N-PCCs decreased with the increase of DS value. Further, N-PCCs nanoparticles could be still formed in a spherical shape similar to chitosan nanoparticles by ionic gelation technique, observed by atomic force microscopy (AFM). Dynamic light scattering (DLS) results suggested that the zeta potential value of N-PCCs nanoparticles decreased with the DS value increasing. Using 5-fluorouracil (5-Fu) as a model drug, in vitro drug release studies indicated that N-PCCs nanoparticles exhibited a similar prolonged release profile as chitosan nanoparticles. The results suggested that N-PCCs nanoparticles could be used as promising nanocarriers for drug delivery applications. (C) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 128: 153-160, 2013