Study of Functionalized Biocompatible Nanomaterials for Disease Diagnosis and Treatment

Abstract

Currently, pathogen identification and therapeutic approaches play important roles in controlling infections. On one hand, the traditional gold standard diagnostic method, i.e., culturing and colony counting, is limited by long waiting times (and thus wasted time), as culturing of most clinical bacterial pathogens requires 1–2 d (much longer times are required for several bacterial species), and low efficiency due to contamination and significant experimental error. On the other hand, the treatment options are limited due to the shortcoming of the pharmaceutical effect and the increased drug resistance. Therefore, rapid and effective detection technologies are urgently needed for an early-stage diagnosis, at which time there are low concentrations of the target pathogen. And research on novel antibiotic agents are especially important for fighting epidemic antimicrobial infections. We focused on studying the bioapplications including disease diagnosis and treatment with functionalized biocompatible nanomaterials. Hereby, the useful tools for rapid and sensitive nucleic acid isolation-detection without large instruments and detergent in the field of molecular diagnostics and synergistic effect of nanomaterials on antibiotic therapy have been studied and developed in our research team. As the representative semiconductor, the ZnO nanomaterials dissolute to ionic zinc (Zn2+) and particle-induced generation of reactive oxygen species (ROS) in the solution which represent the primary mechanism of further applications. We have studied the synthesis routes of ZnO nanomaterials that allow better control of the shape and size of nanomaterials as well as use for nucleic acid extraction-detection and pathogenic bacterium therapy. Meanwhile, diatomaceous earth (diatom), a naturally assembled amorphous silica architecture presents a single morphology as a microscale hollow particle with numerous nanoscale pores in the wall and abundant hydroxyl groups on its surface, which suggesting ease of chemical modification and subsequent use in biological applications. Hereby, we designed the appropriated modification on diatom and applied for sample preparation. The binary nanomaterials (ZnO nanomaterials and diatom) integrated with surface modification and homobifunctional imidoester (HI) cross-linking have been designed for Point-of-care testing (POCT) system. Meanwhile, the synergistic effect of nanomaterials been studied with enhanced antibiotic activity against fungi (Aspergillus fumigatus) and Gram-negative bacteria (Escherichia coli and Salmonella enterica).