Photoacoustic spectroscopy applications

M.W Sigrist, Photoacoustic Spectroscopy, Applications, in Encyclopedia of Spectroscopy and Spectrometry, Academic Press, San Diego 2000, Vol. 3, pp. 1800-1809. 

J. Laufer, D. Delpy, C. Elwell, and P. Beard, Quantitative Spatially Resolved Measurement of Tissue Chromophore Concentrations Using Photoacoustic Spectroscopy Application to the Measurement of Blood Oxygenation and Haemoglobin Concentration, Phys. Med. Biol, 52,141 (2007). 

See also Environmental Applications of Electronic Spectroscopy IR Spectrometers Laser Applications in Electronic Spectroscopy Photoacoustic Spectroscopy, Theory Photoacoustic Spectroscopy, Applications Photoacoustic Spectroscopy, Methods and Instrumentation Surface Studies By IR Spectroscopy Zeeman and Stark Methods in Spectroscopy, Applications. 

See also Laser Spectroscopy Theory Light Sources and Optics Photoacoustic Spectroscopy, Applications. 

See also ATR and Reflectance IR Spectroscopy, Applications IR Spectral Group Frequencies of Organic Compounds Nuclear Quadrupole Resonance, Instrumentation Photoacoustic Spectroscopy, Applications Rayleigh Scattering and Raman Spectroscopy, Theory. 

Spectroscopy Chemical Ionisation in Mass Spectrometry Chromatography-MS, Methods Hyphenated Techniques, Applications of in Mass Spectrometry Inductively Coupled Plasma Mass Spectrometry, Methods Mass Spectrometry, Historical Perspective MS-MS and MS" Photoacoustic Spectroscopy, Applications. 

See also Fibre Optic Probes in Optical Spectroscopy Clinical Applications Fourier Transformation and Sampling Theory Light Sources and Optics Photoacoustic Spectroscopy, Applications Photoacoustic Spectroscopy, Theory Scanning Probe Microscopes Scanning Probe Microscopy, Applications Scanning Probe Microscopy, Theory Surface Plas-mon Resonance, Applications Surface Plasmon Resonance, Theory. 

Poston, P. E., and Harris, J. M., Maximum Likelihood Quantitative Estimates for Peaks Application to Photoacoustic Spectroscopy, Anal. Chem. 59, 1987, 1620-1626. 

The application of infrared photoacoustic spectroscopy to characterize silica and alumina samples is reported. High quality infrared photoacoustic spectra illuminate structural changes between different forms of silica and alumina, as well as permit adsorbate structure to be probed. Adsorption studies on aerosil suggest adsorbed species shield the electric fields due to particle-particle interactions and induce changes in the vibrational spectra of the adsorbates as well as in the bulk phonon band. It is shown that different forms of aluminum oxides and hydroxides could be distinguished by the infrared spectra. 

The technique employed is IR-FT photothermal beam deflection spectroscopy (PBDS). It is an off-shoot of photoacoustic spectroscopy (PAS) [1] and is based on the "mirage detection of the photothermal effect invented by Boccara et al. [2] and shown to result in a spectroscopic technique of remarkable versatility and utility. Some applications of "mirage spectroscopy," mainly in the visible, and theoretical treatments, have been described [3 6]. The method has now been developed for use in the IR. The spectrometer and techniques are described in detail elsewhere [7], but it will be useful to give a brief outline of the principles. 

As pointed out in the previous section, one of unique application of photoacoustic spectroscopy is depth-profiling. The heat which was generated under the surface, propagates to the surface. The time which is needed for propagation to the surface... 

Now X-ray region has been opened to the photoacoustic spectroscopy. However, as seen in this text, the photoacoustic X-ray absorption spectroscopy is still in primitive stage. For the real applications, it seems that the sensitivity should be improved at least 10 times better than now or the photon flux should be increased by focusing or insertion devices. With the specific character of X-ray absorption, e.g. transparency of X-ray and abrupt edge shape absorption profile, this method seems to have hopeful future when the unique photoacoustic application can be conducted. 

Gillette PC, Lando JB, Koening JL (1985) A survey of infrared spectral data processing techniques In Ferraro JR, Basile LJ (eds) Fourier transform infrared spectroscopy -applications to chemical systems, Vol 4 Academic Press, New York, 1-47 Graham JA, Grim WM III, Fateley WG (1985) Fourier transform infrared photoacoustic spectroscopy of condensed-phase samples, In Ferraro JR, Basile LJ (eds) Fourier transform infrared) spectroscopy - applications to chemical systems, Vol 4 Academic Press, New York, 345-392... 

Knshnan K (1988) Characterization of semiconductor silicon using the FT-TR microsampling techniques In Messerschmidt RG, Harthcock MA (eds) Infrared microspectroscopy theory and applications Marcel Dekker, New York, 139-151 Kuo MI, McClelland JF, Luo S, Chien PL, Walker RD, Hse CY (1988) Applications of infrared photoacoustic spectroscopy for wood samples Wood Fiber Sci 20 132-145 Lai Y-Z, Sarkanen KV (1975) Structrual variation in dehydrogenation polymers of comferyl alcohol Cellul Chem Technol 9 239-245... 

The feasibility of thermic and calorimetric detection of the absorbed radiation has been mentioned in the context of grazing-incidence experiments. This is quite close to the class of photothermal techniques with which a number of different detection schemes is employed (Coufal, 1986). Out of these, photoacoustic spectroscopy (PAS) is frequently used in infrared spectroscopy (Graham et al., 1985 Urban et al., 1990 McClelland, 1992) while inspite of its potential, thermal beam deflection has not yet found as many applications as in other spectral ranges, possibly due to the lower availability of suitable lasers (Low and Morterra, 1985). 

Further recent developments in DSC and IR techniques, with respect to the study of SC barrier properties, include step-scan FT-IR photoacoustic spectroscopy [195] and combined microscopic differential calorimetry-Four-ier transform infrared (DSC-FTIR) spectroscopy [196]. The former allows depth profiling of the membrane the latter enables the simultaneous detection of calorimetric and structural modifications during a thermal transition. Technological advances in DSC and IR will, no doubt, continue to expand the application of these techniques to the study of skin barrier function. 

For a summary of the present knowledge of laser-induced photoacoustic spectroscopy, as regards theoretical backgrounds, instrumentation and radiochemical applications to particular problems in aquatic actinide chemistry, see Kim et al. (1990). Since there is no other radiochemical application known in the literature, except the measurement of tritium decay by an acoustic sensing technique, the present discussion is limited to application to actinide chemistry, particularly in aquatic systems. The most interesting field of application is and will be the geochemical study of long-lived... 

Recently, the surface-modified gold nanorods were used as probe materials for surface-enhanced Raman scattering (SERS) [20, 21] and photoacoustic spectroscopy [50]. The SERS can give information on the vibrational modes of organic molecules on or near the gold nanorods, while photoacoustic spectroscopy is a sensitive way to detect photothermal conversion. These methods will open up new applications of gold nanorods as bioprobes. 

Certain aspects of the photoacoustic effect suggest that this technique might be generally applicable to all chiral solids regardless of crystal class, size or perfection, or strength of absorption. Although subsequent theoretical developments and experimental results have caused us to limit considerably the predicted scope of this method, nevertheless, it is possible now to say clearly that the experiment does work and offers prospects for unique results. In this paper we review briefly the nature of the theory and practice of condensed phase photoacoustic spectroscopy and its extension to the measurement of natural circular dichroism, and present initial results for single crystals and powders. 

Photoacoustic Spectroscopy.—Photoacoustic spectroscopy (PAS) and its applications have been recently reviewed. A single-beam i.r. PAS spectrometer has been constructed for the range 800—4000 cm using a broad-band carbon rod spectral source in preference to a laser. A double-beam in-time PAS instrument has been described, in which a single microphone was used to monitor both the... 

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