Dual wavelength spectroscopy

The wavelengths used for each carrier in dual wavelength spectroscopy appear opposite each other in the two columns. Some positions of other absorption bands of cytochromes are also given. 

The properties of mitochondrial suspensions have long been the centre of intense study and the characteristics of the pigments of the respiratory chain have been resolved by dual-wavelength spectroscopy (4 Section 2.4.1). However, mitochondrial preparations may not reflect all the properties found in vivo. 

Another possible method of investigating biological samples that cause light scattering is by dual-wavelength spectroscopy [191], [192], although this method is limited to very special applications. The number of types of equipment used... 

Creely, C.M., Singh, G.P. and Petrov, D. (2005) Dual wavelength optical tweezers for confocal Raman spectroscopy. Opt. Commun., 245, 465-470. 

Cytochrome c oxidase for higher organisms contains two haem chromophores at different reduction potentials, a and a, each with an associated copper centre, Cua and Cub respectively. The sequence of reduction of molecular oxygen by fully reduced, membrane-bound cytochrome c oxidase has been deduced > using dual-wavelength multichannel spectroscopy at low temperature. Initial binding of O a is followed by formation of superoxide and oxidation of haem a. Subsequent reactions include internal electron transfer from haem a and Cub with formation of peroxide. Ferricyanide pretreatment oxidizes only haem a and its associated copper and the initial interaction with O2 again produces superoxide and oxidized haem a. ... 

We have developed a novel ultrasensitive detection method, thermal lens microscopy (TLM), for nonfluorescent species [13]. TLM is photothermal spectroscopy under an optical microscope. Our thermal lens microscope (TLM) has a dual-beam configuration excitation and probe beams [13]. The wavelength of the excitation beam is selected to coincide with an absorption band of the target molecule and that of the probe beam is chosen to be where the sample solution (both solvent and solute) has no absorption. For example, in determination of methyl red dye in water, cyclohexane, and n-octanol, a 514-nm emission line of an argon-ion laser and a 633-nm emission line of a helium-neon laser were used as excitation and probe beams, respectively [21], Figure 4 shows the configuration and principle of TLM [13]. The excitation beam was modulated at 1 kHz by an optical chopper. After the beam diameters were expanded, the excitation and probe beams were made coaxial by a dichroic mirror just before they were introduced into an objective lens whose magnification and numerical aper-... 

Optical spectroscopy is the science of the interaction of optical radiation with matter. In many cases this involves specific transitions between the energy levels (states) of a sample, which are monitored experimentally by the absorption or emission of electromagnetic radiation. In these types of interactions the radiation is considered to be composed of packets of energy called photons, and they have a dual character in that they have both particle- and wave-like properties. As discussed in Chapter 1, the photon energy is related to its wavelength and frequency by ... 

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