The University of Texas at San Antonio (UTSA) studies interfacial relationships between nanomaterials and the life sciences through its Partnership for Research and Education in Materials (PREM) with the Materials Research Science and Engineering Center (MRSEC) at Northwestern University (NU) and the University of Texas Health Science Center at San Antonio (UTHSCSA). The PREM creates a permanent relationship between these institutions to broaden and foster collaborative research and education in materials science. The research entails three principal components: 1) collaborative research in nanomaterials and their applications in various fields, 2) education and training for undergraduate and graduate students, especially, women and other underrepresented minority students, and 3) outreach program for K-12 students and teachers.
The research participants are focused in six thrust areas: 1) Rare Earth-based Dual Purpose Biosensor, 2) Medical Applications of Nanoparticles, 3) Novel Nanomaterials and their Applications in Biology, 4) Using Metal Nanoparticles in Neuroscience, 5) Terahertz Characterization of Nanomaterials for Biological Imaging Applications, and 6) Functionalization of Fibers Employing Low Temperature Pulsed Laser Deposition and Atomic Layer Deposition. This PREM establishes a unique and highly cohesive team enabled to investigate fundamental science questions in these specific thrust areas. The NU-MRSEC plays a critical role in establishing and guiding the PREM program at UTSA, as the NU Materials Research laboratories provide infrastructure and support staff currently not available to UTSA undergraduate and graduate students engaged in these types of research areas.
Our research and outreach efforts throughout the 2013-2014 reporting period have produced significant accomplishments and developments pertaining to nanomaterials and their applications to biology, resulting in 36 Publications, 22 presentations, and 5 Ph.D. and 2 undergraduate student graduations. Our key research achievements are: (1) syntheses of smaller size up- and down-conversion luminomagnetic nanoparticles (NPs); (2) characterization of optical and magnetic properties of nanophosphors; (3) in vitro cell imaging of NPs; (4) deeper optical imaging depth with NIR active NPs; and (5) toxicity studies of nanoparticles. Our observation has confirmed that the NIR excitation (~800 nm) and emission from the nanophosphors possess more penetrating properties than the visible upconversion nanophosphors. . In addition, our PMAO-coated NPs were imaged using a two photon microscope showing that they are easily taken up by fibroblast cells without specific surface functionalization. These nanoparticles were found to be within the cytoplasm as well as the cell nucleus in some cases. Functionalized Au NPs in the presence of glutathione are found to self-aggregate. The aggregation changes the absorption cross-section of the NPs that can be measured by the change in optoacoustic (OA) signal. Detection of the OA signal is accomplished using the Probe Beam Deflection Technique. Our experiments have shown that oxidation-sensing NPs can detect higher levels of reactive oxygen species during the UV-VIS exposures, thereby supporting this method for biological oxidative stress measurement. We have developed a methodology to study the interactions of Cells and nanoparticles combining Biological methods with STEM-HAADF Electron Microscopy methods. We are currently analyzing phytotoxicity of ZnO particles on Alfalfa-Sinorhizobium meliloti in soil as well as the study of A375 melanoma cells (skin cancer) treated with metal-based drugs (Cu-thiomaltol). Our research has shown that using electron holography it is possible to extract the morphology and shape of individual nanoparticles via reconstruction of the phase hologram. Another application of electron holography is the possibility to extract quantitatively physical measurements such as the magnetic and electric contributions into and around nanostructures. By using precession electron diffraction it is possible to extract quantitatively the intensities in electron diffraction and to do crystal refinement for structure determination. Significant progress towards developing novel classical density functional theories for nanoparticles immersed in electrolytes at different conditions has been made. Finally, with a strong support from our NU-MRSEC partner, we have accelerated our high impact outreach effort with local minority-based high school students through "Nano-Day" held at UTSA. In addition, we have strengthened the UTSA - NVC pipeline for underrepresented groups in materials science with regular seminars at NVC presented by UTSA PREM faculty and students.
