1. Photo acoustic spectroscopy of beta amyloids - research overview Group Meeting February 08

3. OTDR pulse width: 100ns-1μs Scope detector 10% fiber splitter Erbium Amplifier 90% PZT RF Amplifier 24V+ Voltage source referencePhoto-acoustic signal First setup goal –generating and characterization of pa signal Wavelength – 1550 nm 1. OTDR

5. Tunable Laser Polarization controller Modulator Function Generator Erbium Amplifier x2 Scope PZT RF Amplifier x3 24V+ Voltage source detector fiber splitter Reference 95% Signal 5% 2. Tunable Laser Wavelength 1535 -1565 nm

7. ~5 micro second PZT

8. Water: Abs coefficient =11.6 cm^-1 heat capacity = 4.184 J cm-3 K-1 Thermal expansion =207 10-6/K ethanol: Abs coefficient =5.7 cm^-1 heat capacity = 1.925 J cm-3 K-1 Thermal expansion =750 10-6/K

9. There is a change of 0.28% in sound velocity for a percent change of glucose concentration

10. 2008002,00030010,000 UVvisibleNear-IRIR nm 1550 peptidic bond (190-250 nm) aromatic residues (~280nm) starching vibration of aromatic residues (3.3, 6.25,6.6 μm ) starching vibration of amide bond ( 5.88-6.25 μm ) bending vibration of aromatic residues (11.1-14.5 μm) Over tones (1000-2600) Spectrum

11. Technion experiment : Nd:YAG fourth harmonic 266nm laser: 1.Insulin

12. 2.lysosin 3.Beta amyloid

13. opo experiment: OPO -optical parametric oscillator

15. Zoom in on first peak 1. insulin 2. water Wavelength ~1660nm

16. Goals for the short future  improving the sensitivity of the measurements  Defining the concentration and absorption coefficient of solutions by pa measurement  Finding the amyloids over tones spectra, and characterize its pa signal  Examine the ability of performing pa measurements in the MIR  Completing the simulation of the pa signal