Preparation, characterization and Chemical modification of cellulose nanowhisker with cationic hyperbranched dendritic polyamidoamine

One special way to overcome the side effects of cancer chemotherapy and to achieve improved therapeutic effects is to develop drug delivery systems that enhancetumor cytotoxicity and cellular entry, but reduce the adverse effects on normal cells. PAMAM dendrimers as nanocarriers can offer several unique properties, such asincreasing the water-solubility, bioavailability and effective release of the polymer-bound drug in the acidiccellular compartments after internalization by tumor cells, while keeping the conjugates stable in the bloodstream [1,2]. Well-known commercial PAMAMdendrimer, as an effective transfection reagent in vitro and in vivo, has high transfection efficiency but has high cytotoxicity at the same time. Considering theadvantages of PAMAM dendrimer as an transfection reagent, researchers paid much attention to develop potential gene vectors based on PAMAMs with highertransfection efficiency as well as lower cytotoxicity based on degradable systems. Cellulose nanowhiskers (CNWs) are a subject of intenseinvestigation due to their exceptional physical and mechanical properties, nanoscale dimension, highspecific strength, availability, biodegradability and ability to be functionalized with specific surface chemistries through a variety of chemical processes[3,4].In this work Polyamidoamine (PAMAM) dendrimers were grown onto the surface of cellulose nanowhiskers (CNWs-NH2) by a divergent method, the PAMAMgrafted CNWs (PAMAM-g-CNWs) hybrid materials were obtained