1. The study of cysteine molecule coated magnetic Fe 3 O 4 nanoparticles via sonochemical method for bio-applications Kevin J. Schilling, Joo Seob Lee, and Patrick A. Johnson Biointerfacial Engineering Laboratory Department of Chemical & Petroleum Engineering IntroductionMethods ACKNOWLEDGMENTS Advisor : Dr. Patrick A. Johnson Mentor: Joo Seob Lee We acknowledge the financial support from the McNair Scholars Program at the University of Wyoming Problem Data Analysis Hypothesis Bio-Application (1) Magnetic nanoparticles, functionalized with cysteine improve the solubility and performance characteristics for biomaterials in aqueous & non-aqueous conditions. (2) Different conditions such as sonication time, temperature, and the concentration of DL-Cysteine will affect the magnetic Cys- Fe 3 O 4 colloidal suspensions due to the surface structure of Cys-Fe 3 O 4. Transmission Electron Microscopy (TEM) Scanning Electron Microscopy (SEM) Determine structure Magnetic core with shell View individual particle and clusters Enzyme Immobilization DNA Binding Ability Biosensors Two primary binding groups Carboxyl (-COOH) Amine (-NH 2 ) Covalent binding This study will examine cysteine coated magnetic nanoparticles (Cys-Fe 3 O 4 ) fabricated with sonochemical approaches, using (1) metal salt mixtures (e.g., Fe 3+, Fe 2+ ) and (2) iron pentacarbonyl (Fe(CO) 5 ) in conjunction with a small molecule surfactant. A comparison of the two methods in order to create more uniform dispersion will be performed in order to prevent cysteine-cysteine interactions on the surface of Cys-Fe 3 O 4. + ) ) ) Time, t Sonicate iron pentacarbonyl for 3 hours Wash with solvent (e.g. double-distilled water, acetone, or methanol) DL-Cysteine Iron Magnetic Nanoparticle Double helix structure in DNA Phosphate groups on 3’ and 5’ ends of sugar backbone Amine binding Nitrogen attack phosphate Carboxyl binding Carboxyl group (C=O) attack phosphate Possible addition of acid Chemically bind Cys-Fe 3 O 4 to glass substrate Immobilize the enzyme on the Cys-Fe 3 O 4 coated surface Get diagnostic reading from enzyme reaction TEM Fourier-Transform Infrared Spectroscopy (FT-IR) & Raman Spectroscopy Characterization of coated/uncoated particles Tilted image of dried particles (3D) Determine size (nm) and morphology Fe 3 O 4 Cys-Fe 3 O 4 Add iron pentacarbonyl Fe(CO) 5 Inject DL-Cysteine into solution Sonicate for 3 hours Wash with solvent Let (magnetically) precipitate Fe 3 O 4 ) ) ) Time, t Iron Pentacarbonyl Iron Magnetic Nanoparticle Dynamic Light Scattering & Zeta Potential (+/-, mV) Determination of size and colloid stability Measure surface charges and the particle mobility SEM FT-IR In past years, magnetic Fe 3 O 4 nanoparticles have been a tremendous asset to the biomaterial field and as such there has been a high desire to synthesize and optimize these nanoparticles. These magnetic Fe 3 O 4 particles are very diverse. They can be used as catalysts, be used in drug delivery, or aid in magnetic hyperthermia treatment. These nanostructured particles being created have super paramagnetic behaviors; these magnets can flip their magnetic direction due to either temperature or the presence of a magnetic field. In contrast, magnetic Fe 3 O 4 particles can switch their magnetic field to attract the other particles and aggregate and precipitate out of solution. Structure of DNA DI-Water Cys-Fe 3 O 4 Complex