The Raman scattering amplification associated with this phenomenon is known as surface-enhanced Raman scattering (SERS) spectroscopy . To monitor PB NPs from the background tissue in vivo, we also developed a new 700-nm-region stimulated Raman scattering (SRS) source (pulse energy up to 200 nJ and repetition rate up to 50 kHz) and implemented optical-resolution photoacoustic microscopy (OR-PAM). In this paper a multi-wavelength optical-resolution photoacoustic microscopy (OR-PAM) system using stimulated Raman scattering is demonstrated for both phantom and in vivo imaging. However, differentiation of photoacoustic signals is non-trivial hence specificity can be poor. Photoacoustic Raman spectroscopy is a nonlinear spectroscopic technique based upon the selective population of a given energy state of a system by the process of coherent Raman amplification (stimulated Raman scattering). Vibrational resonance Raman scattering. Owing to its high chemical specificity and noninvasive detection capability, Raman scattering has been widely employed in cancer screening, diagnosis, and intraoperative surgical guidance in the past ten years. United States Patent 4197009 . The sensitivity of a new spectroscopic technique, photoacoustic Raman spectroscopy (PARS), has been improved substantially by the use of high-peak-power pulsed lasers. Conjugation of Raman reporter 4‐aminothiophenol (4‐ATP) onto AuNFs yields a surface‐enhanced Raman scattering (SERS) fingerprint for Raman spectroscopy/imaging. Proc. It is proposed that Raman excitation with photoacoustic detection can successfully address the problem of chemically specific imaging in deep tissue. Photoacoustic spectroscopy is the measurement of the effect of absorbed electromagnetic energy (particularly of light) on matter by means of acoustic detection. However, ther e are controversies on the identification of modes [20-21]. The Raman amplifier has been constructed using 4.5 km of dispersion shifted fiber, a 1651 nm DFB seed laser and a commercial 4W … Two coherent beams 15, 17 of monochromatic radiation are directed through a sample of material. Circulating tumor cells (CTCs) have been proposed as an important biomarker of tumor metastasis. A very common pulsed optical source is a frequency-doubled Q-switched Nd:YAG laser. The development of a stimulated Raman scattering photoacoustic (SRS-PA) spectrometer is presented. Abstract: A method and apparatus for spectroscopic material anaylsis are provided. Multimodality Photoacoustic and Raman Imaging. Raman laser at 1197 nm for photoacoustic imaging of fat Rui Li, *Mikhail N. Slipchenko, Pu Wang, and Ji-Xin Cheng Purdue University, Weldon School of Biomedical Engineering, West Lafayette, Indiana 47907 Abstract. low frequency Raman scattering ofCdS 1-xSe x, only the spheroidal modes ofl=0 (symmetrical mode) and forl=2 (quadrupole mode) are observed. Electronic (and vibronic) resonance Raman scattering. A tuning mechanism 14 adjusts the frequency difference between the radiation beams 15, 17 to equal substantially the vibrational … In situ Raman scattering of graphene further confirms that the temperature of graphene under laser pulses rises above the boiling point of water but still remains too low to vaporize graphene and create graphene plasma bubbles. Ultrasound detection provides a simple way to discriminate against laser-induced breakdown and allows for the quantification of the stimulated Raman scattering process where direct optical detection is not available. The full spectrum acquisition can be a time consuming procedure diminishing the advantages of stimulated Raman photoacoustic imaging. It is important, since, unlike spontaneous Raman scattering spectroscopy, which provides with the whole vibrational spectrum for a single wavelength excitation, stimulated Raman scattering excitation is limited to a single vibrational line. Normal pure vibrational Raman scattering. However, the fixed 532 nm output is not suitable for spectroscopic PAM. To accomplish this goal, significant optical scattering in tissues has to be overcome while achieving molecular specificity without resorting to extrinsic labeling. Photoacoustic imaging is a novel imaging technology for visualizing optically-absorbing structures in vivo with simultaneous high contrast and high spatial resolution. In the apparatus, a molecular vibrational mode is excited by the SRS process. Raman spectroscopy has an intrinsic sensitivity to the chemical content of the bone, but its application to study bones in vivo is limited due to strong optical scattering in tissue. By Mirela M. Barsan (2103418), Ian S. Butler (594292), Denis F. R. Gilson (2103412), Ralph O. Moyer (2103415), Wei Zhou (24328), Hui Wu (219526) and Terrence J. Udovic (1272093) Cite . A one-for-all organic agent for integrated triple-modality imaging-guided cancer surgery has been developed, in which the fluorescence, photoacoustic (PA), and Raman properties could be precisely tuned and boosted by tuning the molecular structure and intramolecular motions. Multimodality Raman and photoacoustic imaging of surface-enhanced-Raman-scattering-targeted tumor cells Wei Shi, aRobert J. Paproski,a,b Peng Shao, Alexander Forbrich,a John D. Lewis,b and Roger J. Zempa,* aUniversity of Alberta, Department of Electrical … We demonstrate the feasibility of developing such an optical imaging modality by combining the molecularly specific stimulated Raman excitation with the photoacoustic detection. A locked padlock) or https:// means you've safely connected to the .gov website. The theory for generation of photoacoustic signals from stimulated Raman scattering is outlined, and vibration-rotation Raman spectra for CO 2 and CH 4 are presented. The coherent anti-Stokes Raman scattering (CARS) and photoacoustic Raman spectroscopy (PARS) spectra of gaseous CHF2Cl and CH3CF2Cl in the 3000 cm-1 region are reported for the first time. The development of a stimulated Raman scattering photoacoustic (SRS-PA) spectrometer is presented. The discovery of the photoacoustic effect dates to 1880 when Alexander Graham Bell showed that thin discs emitted sound when exposed to a beam of sunlight that was rapidly interrupted with a rotating slotted disk. The vibrational excitation energy is converted to heat by vibrational relaxation. Raman scattering has long been used to analyze chemical compositions in biological systems. A 1-ns pulse width ytterbium-doped fiber laser is coupled into a single-mode polarization maintaining fiber. Many approaches have been … Lipidrich tissue, such as atherosclerotic plaques and myelinated nerve fibers, exhibits an optical absorption peak near 1210 nm. Photoacoustic Raman spectroscopy Download PDF Info Publication number US4269509A. The molecular population at this excited level will be reduced by the subsequent collision-induced vibrational relaxation. This dual modal probe is prepared by doping a semiconducting conjugated polymer with polydopamine (PDA) through a one-pot reaction. In vivo evaluation of HA‐4‐ATP‐AuNFs‐DOX on tumor‐bearing xenografts demonstrates its high efficacy in eradication of solid tumors in NIR‐II under PA–Raman dual image‐guided photo‐chemotherapy. Spectroscopic photoacoustic microscopy in the 1064–1300 nm range using a pulsed multi-color source based on stimulated Raman scattering Abstract: Photoacoustic microscopy (PAM) provides excellent image contrast based on optical absorption. The Journal of Biomedical Optics (JBO) is an open access journal that publishes peer-reviewed papers on the use of novel optical systems and techniques for improved health care and biomedical research. Multimodality Raman and photoacoustic imaging of surface-enhanced-Raman-scattering-targeted tumor cells Wei Shi, aRobert J. Paproski, a,b Peng Shao, Alexander Forbrich, a John D. Lewis, b and Roger J. Zemp a,* a University of Alberta, Department of Electrical and Computer Engineering, Second Floor ECERF, 9107-116 Street, Raman scattering in an optical fibre has been utilized as the near-infrared source for a pulsed photoacoustic spectroscopic study of liquid hydrocarbons. Share sensitive information only on official, secure websites. Raman scattering efficiency can be enhanced by factors >10 8 when a substance is adsorbed on or near rough metal surfaces. US4269509A US06/034,512 US3451279A US4269509A US 4269509 A US4269509 A US 4269509A US 3451279 A US3451279 A US 3451279A US 4269509 A US4269509 A US 4269509A Authority US United States Prior art keywords beams radiation material apparatus means Prior art date 1978-05-26 Legal status (The … We demonstrate a simple approach to increase the number of wavelengths by using stimulated Raman scattering (SRS) in an … Author / Creator Shi, Wei; Tumor metastasis is referred to the spread of cancer from one to another unadjacent part of the body, which results in more than 90% of tumor deaths, and however is still poorly understood. Several vibrational bands are observed related to C−H stretch fundamentals of CHF2Cl isotopomers, and to CH3 stretches and the first overtone of CH3 deformation of CH3CF2Cl. In the apparatus, a molecular vibrational mode is excited by the SRS process. These huge increases in Raman scattering are primarily caused by the increased intensity of the electromagnetic … AB - This paper presents the development of a Raman fiber amplifier optical source with a maximum output power of 1.1 W centered around 1651 nm, and its application in miniaturized 3D printed photoacoustic spectroscopy (PAS) trace gas sensing of methane. An open-cell system is described and the performance criteria for practical photoacoustic instrumentation are discussed. Normal electronic (and vibronic) Raman scattering. We herein report a bandgap engineering strategy to develop an intrinsically Raman-photoacoustic (PA) active probe that is based on semiconducting conjugated polymers. Raman, FTIR, Photoacoustic-Infrared, and Inelastic Neutron Scattering Spectra of Ternary Metal Hydride Salts A2MH5, (A = Ca, Sr, Eu; M = Ir, Rh) and Their Deuterides . The vibrational spectra (Raman, photoacoustic and Fourier transform infrared and inelastic neutron scattering) ... Raman and neutron inelastic scattering (INS), and applied this approach in the case of Mg 2FeH 6/D 6. Abstract: Photoacoustic microscopy (PAM) provides excellent image contrast based on optical absorption. References Owing to much weaker acoustic scattering in tissues as compared to optical scattering, photoacoustic detection of harmonic molecular vibration has enabled significant improvement in imaging depth. Additionally, it can be used for stimulated Raman imaging in deep tissue, provided that the generated photoacoustic signal is sufficiently strong. Photoacoustic Raman spectroscopy . photoacoustic Raman spectroscopy Yuanqin Yu, ... ulated Raman scattering process occurs, and the molecules are populatedfrom the ground vibrational level to an excited vibrational level. Discrete Raman-shifted wavelength peaks extending to nearly 800 nm are generated with pulse … infrared absorption or Raman scattering, the imaging depth is limited to the ballistic photon mean free path, which is a few hundred microns in a biological sample. Units and orders of magnitude. Photoacoustic imaging employing molecular overtone vibration as a contrast mechanism opens a new avenue for bond-selective imaging of deep tissues.