Electronic Thesis and Dissertation Repository

A pH-sensitive Delivery System for the Prevention of Dental Caries Using Salivary Proteins

Yi Zhu, The University of Western Ontario

Abstract

Dental caries remains one of the most common chronic diseases worldwide. Salivary proteins such as histatins have demonstrated biological functions directly related to tooth homeostasis and prevention of dental caries. However, histatins are susceptible to the high proteolytic activities in the oral environment. Therefore, pH-sensitive chitosan nanoparticles (CNs) have been proposed as potential carriers to target major oral diseases that occur under acidic conditions (e.g. dental caries and dental erosion). Four different types of chitosan polymers were investigated and the optimized CNs successfully loaded histatin 3 and released it selectively under acidic conditions. Through loading the survival time of histatin 3 was increased by two-fold in diluted whole saliva. Results from biofilm experiment have demonstrated both blank and histatin 3-loaded CNs were able to reduce biofilm growth of Streptococcus mutans. The results of this study have demonstrated the potential of using blank CNs alone as antibacterial agent for oral applications in addition to the potential of CNs as protein carriers, especially for diseases occurring at acidic conditions.