Synthesis and study of and controlled release from nanoparticles and their networks based on functionalized hydroxypropylcellulose

The structure of hydroxypropylcellulose (HPC) was modified by covalently attaching either vinyl groups linked by degradable esters or methacrylate groups. The vinyl groups allowed for chemical linking of the HPC chains into nanoparticles through a free radical polymerization process above its low critical solution temperature. The HPC nanoparticles with degradable moieties in aqueous solution were monitored using dynamic light scattering technique as a function of time. The degradation rate increased at either low or high pH values. Residual, un-cross-linked vinyl groups on the surface of the nanoparticles were further linked together, forming a network of nanoparticles. The controlled release of biomolecules from this network was correlated with the primary structure that comprised cross-linked polymer chains in each individual particle and the secondary structure that was a system of cross-linked nanoparticles.