Fluorescence detected circular dichroism FDCD

Fluorescence-detected circular dichroism (FDCD) is a chiroptical technique in which the spectrum is obtained by measuring the difference in total luminescence obtained after the sample is excited by left- and right-circularly polarized light. For the FDCD spectrum of a given molecular species to match its CD spectrum, the luminescence excitation spectrum must be identical to the absorption spectrum. 

Since polypeptides are chiral polymers, the chromophore arrangement shows some chirality. Therefore, additional information on the chromophore arrangement in the ground state, as well as in the excited state, may be obtained from chiroptical spectroscopy, such as circular dichroism (CD), circularly polarized fluorescence (CPF) [43], and fluorescence-detected circular dichroism (FDCD) [44). 

Application of fluorescence-detected circular dichroism (FDCD) to the determination of the major pterin (L-monapterin) from Escherichia coli has been published <01H(54)283>. Identification of (6/ )-5,6,7,8-tetrahydro-D-monapterin as the native pleridine in Tetrahymena pyriformis has been reported <01HCA918>. A novel modified pterin has been isolated from... 

Magnetic circular dichroism, a more recent development, has been used mainly in the study of haem proteins and has been reviewed recently as has been fluorescence-detected circular dichroism (FDCD). 

A new method which is more specific than circular dichroism is fluorescence detected circular dichroism (FDCD). In this method the intensity of light emitted by a fluorescent chromophore excited by left and right circularly polarized light is used to measure the circular dichroism. The FDCD method thus gives information about the conformation of a polymer in the immediate neighborhood of fluorescent groups. 

Fig. 12. An illustration of how fluorescence detected circular dichroism (FDCD) allows the measurement of the CD of a fluorescent chromophore in the presence of a non-fluorescent, but optically active chromophore. The usual CD measures the sum of the CD of L-cystine and L-tryptophan. The FDCD measures only the fluorescent L-tryptophan. (Reprinted from D.H. Turner, M.F. Maestre, and I. Tinoco, Jr. J. Am. Chem. Soc. 96, 4340 (1974).)...

In fluorescence-detected circular dichroism (FDCD) the difference in total emission intensity is used to monitor differences in circularly polarized absorption. This spectroscopic technique was developed in the early 1970s in the laboratory of Professor I. Tinoco at the University of California,... 

Muller G, MuUer EC, Maupin CL, Riehl JP. The Measurement of the Fluorescence Detected Circular Dichroism (FDCD) from a Chiral Eu(III) System. ChemCommun 2005 28 3615-3617. 

Unlike CD, the measurement of CPL is still mainly dependent on the use of custom-made instruments that have been designed, developed and improved by a limited number of research groups around the world over the last three decades [36,38,41,42,45,52,59-63]. However, the growing interest in developing chiral luminescent probes, and in particular Ln(in)-based systems, has resulted in the advertising and some availability of commercial instrumentation. The first commercial CPL spectrometer, which essentially consists of two CD spectrometers with the second one used as the emission spectrometer, was manufactured by JASCO Inc., the JASCO CPL-200. More recently, the company OLIS Inc. developed its Polarisation Toolbox to support fluorescence, polarisation of fluorescence, anisotropy, CPL, CD, and FDCD (fluorescence detected circular dichroism) measurements for its CD instrumentation. As of Febmary 2012, only CPL-related studies using the JASCO CPL-200 instrument have appeared in the hterature [64-67]. 

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