Interdisciplinary Interactions : Session-I I

1. Interdisciplinary Interactions : Session-I I Nanotechnology Research at Texas A&M April 16th 2008 Sponsor: Texas Engineering Experiment Station (TEES) - NANSA - Nanotechnology and Nanoscience Student Association

2. BIOMEDICAL ENGINEERING Gerard Coté gcote@tamu.edu 845-5494 • Research: • Dr. Coté directs the Optical Biosensing Laboratory, where research focuses on the development of macro-scale to nano-scale systems using lasers, fiberoptics and electronics for objectives that include: • Non- or minimally-invasive methods of testing blood sugar levels in diabetics using fluorescence and polarization-based approaches. • Detection of analytes in cells and cell culture media • Surface-enhanced Raman spectroscopy platforms and sensors to detect body chemicals such as β-amyloid for Alzheimer’s disease and other biomarkers and pathogens.

3. Nano-based Platforms for Surface-Enhanced Raman Spectroscopy Nanofluidic Biosensor Gold nanoparticles are mechanically trapped at the entrance to a nanochannel to provide a controlled, reproducible site for SERS enhancement. SERS spectra of β-amyloid protein display concentration and conformation dependence Nanoshell Platform Nanoshell platforms allow for significant SERS enhancement that is consistent across the platform surface instead of being dependent on “hot spots” of high enhancement that limit other SERS approaches Nanoshell core and shell ratios are tuned to desired NIR excitation λ Nanoshells are functionalized to mimic neuron cell surfaces for specific binding to β-amyloid

4. BIOMEDICAL ENGINEERINGDr Ken Meissner kmeissner@tamu.edu458 - 0180 Research • Biomaterials • Biophotonics Imaging • Nano- and Micro-scale Materials Research tools • Femto-second Laser • Fluorescence Lifetime Microscope • Quantum Dots • Silica/Polymer Microspheres Research projects • Synthesis of Nanocrystals/Microspheres • Whispering Gallery Modes • Nano- and Micro-scale Sensing Elements • Quantum Dot Energy Transfer

5. Current Projects

6. Dr. Yeh: Tissue Microscopy Lab E2* E2 hvin hvout hvout hvin E1 E1 Our work aims to use nonlinear optical microscopy (NLOM) to bridge the understanding of molecular cell biology and chemistry with tissue/organ properties and function.  An ultra fast laser (~ 10 fs) is used to generate high resolution images by observing weak nonlinear processes. ~ 10 fs ~ 133 nm Bandwidth Two Photon Excitation Fluorescence Second Harmonic Generation

7. Areas of Interest • Instrumentation: • Develop imaging system that uses ultra fast pulsed laser (~ 10 fs) to generate high resolution images of biological structures and processes. • Spectroscopy/ microscopic biomechanics: • Cornea • Characterizing structure and mechanical properties • Skin Optical Clearing • Controlling the optical properties of skin • Angiogenesis • Characterizing the factors leading to the formation of blood vessels • Mechanobiology: • Examining the reorganization of microscopic structures that affect the mechanical properties of tissues as a whole Cornea Skin Clearing Angiogenesis Stretched collagen gel with seeded fibroblasts

8. Biomedical EngineeringDr Javier Jojavierjo@tamu.edu 458 - 3335 Research: • Bio photonics • Optical spectroscopy and Imaging • Optical bio sensing • Physiological Signal processing and mathematical modeling • Atherosclerosis, Cancer detection Research tools: • Time resolved fluorescence spectroscopy apparatus • Fluorescence lifetime Imaging apparatus Research projects: • Fluorescent nano-micro particle characterization and sensing • Atherosclerotic plaque detection in vivo at early stage • Clinical tools for early stage cancer detection

9. Fluorescence Lifetime Imaging System Imaging Bundle Illumination GRIN Lens WD 600 μm 200 μm FOV ICCD Control Sync 10x/20x Handheld Probe 1 mm ExcitationFiber MCP- PMT Delay Generator Delay Generator Laser  = 337nm Fluorescence Monochromator ex Laptop em 2.5 GHz BW PC-Scope Dye Module N2 Laser Filter wheel Time Resolved Fluorescence Spectroscopy

10. Biomedical Micro/Nano Devices Lab 1.0 120 Sensor 0.9 Emission 100 0.8 Sensor 0.7 Absorbance 80 0.6 0.5 60 Relative Intensity Absorption Coefficient (cm-1) Algilica microsphere containing glucose oxidase and 02 indicator 0.4 Polyelectrolyte multilayers with reference fluorophore 40 0.3 0.2 20 0.1 0.0 0 400 450 500 550 600 650 700 750 800 Wavelength (nm) m 15 mm 15 m 20 mm Our goal is to develop implantable microparticle-based luminescent sensors serving as a platform to detect glucose or other analytes via minimally-invasive transdermal optical measurements. Absorbance and emission spectra for the O2-sensitive dye (right peaks), as well as the reference dye (left peaks), allowing for excitation of both dyes with green light and collection in the orange and red. This cartoon shows the desired placement of our microparticle sensors in the dermal layer of the skin (left and middle), as well as the type of device that could be used to make optical measurements through the tissue (right). The SEM image on the left shows the size and morphology of the algilica microspheres. The confocal image on the right shows the O2-sensitive dye (blue) immobilized throughout the microspheres and the reference dye (purple) immobilized inside the nanofilm on the particles’ surface (false coloring). Hybrid organic-inorganic matrix with nanofilm coating provides housing for immobilized enzyme and dyes and enables “fine-tuning” of response properties through precise control of material diffusivities.

11. Biomedical Micro/Nano Devices Lab [b-D glucose] Intenstiy 0 mg/dl 0 mg/dl 550 570 590 610 630 650 670 Wavelength (nm) Operation principle: Changes in local [O2] from glucose oxidation result in relative emission intensity changes (ratiometric measurement). In-vitro testing apparatus (above and below). Sensors respond rapidly to glucose and are reversible with one of the highest reported sensitivity to date. E.W. Stein, P.S. Grant, H. Zhu, M.J. McShane, Anal Chem, 2007