A Master of Science thesis in Chemical Engineering by Marah Mazen Mahmoud entitled, “The Optimization of Modified Composite Nano-materials as a Novel Approach to Dental Hygiene Remediation”, submitted in December 2019. Thesis advisor is Dr. Taleb Ibrahim and thesis co-advisor is Dr. Sarah Dalibalta. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).
Oral diseases have always been a challenge to contend with in the modern world, especially with the adoption of unhealthy lifestyles. These habits have contributed to the growth of S. mutans, P. gingivalis, and H. pylori, among other oral bacteria that encourage the development of dental caries, periodontal diseases, and cancer. To battle these diseases, conventional methods such as toothpastes and mouthwashes have been used and unconventional methods such as carbon compounds and nanoparticles have been developed. The complexation of cationic surfactants and smectite clays has been explored and an example of such an organoclay is the one made of cetylpyridinium chloride (CPC) and montmorillonite (Mt). In this study, the aforementioned organoclay was prepared and optimized with respect to CPC uptake by varying the contact time between 1 hour and 3 days, varying the CPC concentration between 5.11 × 10&'M and 4.52 × 10&*M, and varying the temperature between 25°C and 55°C. The experiments showed that shaking the complex was a better approach to intercalation than using the magnetic stirring plate, and that a 24-hour contact period at a moderate concentration of 1.44 × 10&*M at 25°C provided the highest level of intercalation and relatively low levels of desorption. Additionally, UV radiation had no effect on the intercalation extent of CPC with montmorillonite. The prepared solids were then tested on saliva samples plated in nutrient agar. These experiments showed that the prepared complex retained its antibacterial behavior through a likely combination of adsorption and lysis.