I. Infection control: exploration of siliceous zeolite MFI films as coatings for implantable devices II. Alternative approaches for post-operative infection control using pre-and pro-biotics: a meta-analysis

Abstract

The prevention and control of infections associated with indwelling medical implants has remained a top goal for biomedical researchers and clinicians in associated fields. Multiple routes have been explored for this purpose, including drug-based approaches, materials-based approaches, non-drug biological approaches, etc. Although drug-based approaches have long been the mainstay of clinical applications, alternative approaches that use the materials of the implanted devices themselves, or that use non-drug based biologicals, such as pre- and pro-biotics, offer interesting and potentially useful alternatives, particularly with the rise of antibiotic-resistant bacteria, as well as our increasing understanding of the potential negative, long-term consequences that arise with the use of drugs that fight infections. For instance, materials that can be used as antimicrobial agents have been investigated as coatings for indwelling devices, which could allow for post-operative local infection control without the need for further interventions. Because of their unique interactions with biomolecules and biological surroundings, nanostructured, porous materials, like zeolites, have been suggested as suitable materials for such applications, as well as many others in tissue engineering, and drug delivery systems. The focus of Part (a) of this dissertation is explore a unique material system, pure-silica zeolite MFI, which has only recently begun to be explored for its potential utility in this area due to its unique, three-dimensional pore architecture, high surface area, high thermal and chemical stability, and other unique physicochemical properties that could make it particularly useful in terms of biocompatibility. Here, we synthesize and characterize these pure-silica zeolite MFI in film form through X-ray diffraction, electron microscopy, and common biocompatibility analyses (Enzyme-linked Immunosorbent Assay (ELISA), Bicinchoninic Acid Assay (BCA), and WST -- 1 Cell Proliferation Assay) to explore their potential utility as coatings for implantable devices, particularly towards infection control. The synthetic films successfully demonstrated an ability to be biocompatible and to be a candidate for further studies on biofilm reduction. Part (b) of this dissertation focuses on the characteristics of the target habitat, properties of the probiotic species, and how the probiotic is given are all factors that may impact the effectiveness of probiotic establishment in preexisting microbial communities. However, a significant information gap that impedes microbiome engineering is the relative relevance of variables. We conducted a review and meta-analysis of existing research that looked at the effects of probiotic introductions in human and animal stomachs to fill this information gap. The results of this work showed that, due to the recent improvements in analytical techniques that enable researchers to understand the process of establishment more fully in various biomes, the exploration of pre- and pro-biotics has ample room for more detailed, exhaustive establishment studies. While this remains a gap in the current literature, it points to a clear opportunity for researchers to further explore this non-drug-based approach to infection control.