Synthesis of water dispersed nanoparticles from different polysaccharides and their application in drug release

This work describes an original method to synthesize nanoparticles of starch (NPS), cellulose (NPC), and cellulose/hemicellulose (NPCH) from corn starch (S), microcrystalline cellulose (MCC) and hemp fibers (H), respectively. The synthesis is simply based on the treatment of the latter with trifluoroacetic acid. The resultant nanoparticles are easily dispersed in aqueous solutions. The size of these quasi-spherical particles, as measured by TEM and AFM, is less than 10nm. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction analysis (XRD) of NPC revealed the loss of original cellulose crystallinity and formation of cellulose II structure after dispersion in water, while the structures of NPCH and NPS were found to be amorphous. Thermogravimetric analysis (TGA) results indicated that the resultant NPC and NPS undergo a two-step pyrolysis, whereas the unprocessed MCC and S undergo one-step pyrolysis. Curcumin was chosen as a model drug. As a model drug release system, NPS were found to release curcumin in a controlled way through a pH-dependent mechanism, with release capacity of about 43% and 65% of the original loaded curcumin under pH 7.4 and 1.2, respectively.