From diatoms to malaria: synthesis and application of functional materials

Abstract

This dissertation focuses on two projects that attempt to solve two unique challenges. Biomimetic synthesis inspired by diatoms provides the mechanism for developing functional materials under ambient conditions. The goal of this half of this thesis was to capitalize on the simplicity and ease of morphological control to encapsulate functional enzymes such as nitrilase and ƒÒ-glucosidase within the growing silica matrix. This matrix serves to protect the enzymes from degradation and enhances their shelf-lives. Also, piezoelectric inkjet printing techniques were utilized to pattern these enzyme-encapsulated substrates onto reactive surfaces toward the design of patterned materials. The second half of this thesis focuses on developing alternative strategies for malarial diagnostics. Malaria¡¦s prevalence in most developing countries creates a financial burden on residents as well as the health organizations trying to eradicate the disease. Paramount to effective treatment is accurate and efficient diagnosis of patients in low resource settings. Although significant progress has been made toward diagnostic strategies in these settings, the current ¡§gold standards¡¨ still are not capable of being effective in the most remote regions, due to their reliance on electricity or sensitive reagents. The second half of this thesis is focused on circumventing the challenges of low resource diagnostics through alternative diagnostic strategies and novel sample processing technologies. Using surface tension forces to separate aqueous reaction chambers, complex biological samples can be processed to collect, purify, and concentrate biomarkers for malaria diagnosis. Capitalizing on the high affinity of Histidine-Rich Protein-II (pfHRP-II) towards Ni(II)NTA chelation, this sample processing technology has been demonstrated to collect and isolate this protein from human whole blood and plasma with modest yields and purity. In addition, a novel coffee ring diagnostic strategy has been developed that captures pfHRP-II and processes it within the drying drop. Utilizing radial flow, this assay is capable of concentrating a signal into a small ring visible by the naked eye. This is the first time that this phenomenon has been used as a diagnostic platform. Whether it is for improving enzyme longevity or diagnosing malaria in the field, these functional materials serve to improve the overall wellbeing of mankind.