Spectroscopic probes, biological

Self-assembly and nanotechnology are advancing rapidly, but the challenge still remains to develop a means of fabrication and manufacturing. The rapid developments in synthetic chemistry produce myriad new polymeric and composite materials. These advances are enhanced by progress in optical, micromechanical, and spectroscopic probes. The miniaturization and diversification of synthesis through biological or combinatorial approaches provide unprecedented... 

Varadaraj R, Branham KD, McCormick CL, Bock J (1994) Analysis of hydrophobi-cally associating copolymers utilizing spectroscopic probes and labels. In Dubin P, Bock J, Davis R, Schulz DN, Thies C (eds) Macromolecular complexes in chemistry and biology. Springer-Verlag, Berlin, p 15... 

Although DFM and TFM are important contributions to the range of spectroscopic probes available for application to biochemical studies, other properties of these fluorinated amino acid analogues can also be of use. For example, the subtle change in size of the thiomethyl group and the alteration in the electronic properties of the sulfur atom in these methionine analogues could be useful properties to explore biological systems. In order to obtain... 

Recently, attention has been focused on lanthanoid/crown ether complexes,5 since they may be used for lanthanoid ion separation, for stabilizing unusual oxidation states, and for studying high coordination numbers, Moreover, lan-thanoid(III) ions are increasingly used as spectroscopic probes in systems of biological interest.6... 

Selective analytic and spectroscopic methods for analyzing biomimetic model complexes bound to the support are rather limited, and a detailed characterization of such hybrid materials is much more challenging than of soluble molecular complexes. If local spectroscopic probes are available, IR spectroscopy, gel-phase or solid-state NMR spectroscopy, EPR spectroscopy, or (diffuse reflectance) UV-vis spectroscopy is applicable. Useful IR spectroscopic labels include CO, C=N, E-H, M=E, and M=E stretching vibrations as long as they are either very intense or are separated from the matrix vibrations. For EPR spectroscopic analysis, metal isotopes with nuclear spin 1 0 are suitable. Biologically interesting metal ions include (7 = 7/2, 99.76%), Mn I =512, 100%), Co (7 = 7/2, 100%), 3/65cu (7 = 3/2, 69.09% 7 = 3/2, 30.91%), and (7 = 5/2, 15.72% ... 

Coordination numbers vary wildly with both the nature of the ligands bonded in the inner coordination sphere and the composition of the solutions, although CN=9 is often found (cf the acetonitrile solvates). This establishes that the inner coordination sphere of the lanthanide ions is easily adjustable to the environment in which these ions are exposed. Henceforth, the versatility and adaptability of these elements which are found in many compounds, including organometallic molecules, and which are used as spectroscopic probes in complex biological or environmental systems. 

In this article the interpretation of various P NMR spectroscopic parameters, particularly chemical shifts and coupling constants will be described. A major emphasis will be placed on newer developments in 3ip NMR methods which have considerably expanded the utility of this important spectroscopic probe in organic and biological structure determination. 

With the realization of improvements in the measurements and theoretical calculation of intensities, ROA will assume a place of special importance among our spectroscopic probes of the structure and dynamics of molecules of biological interest. 

One of the principal driving forces behind our efforts with Cd NMR spectroscopy has been the desire to develop a clean spectroscopic probe for zinc and calcium in biological systems. The first observation of Cd signals from a metalloprotein was made by the Yale group headed by Armitage and Coleman (45d). Other Cd observations appeared quickly by Sudmeier (45c) at... 

Another attachment that can be effected to a Raman spectrometer is a remote probe. This consists of a fibre optic cable that passes the laser beam to a sample outside the conventional sampling chamber. This can be of use in many different applications, the most obvious of which is where the sample is too large or complex to fit into the instrument. In vivo biological studies utilize a fibre optic probe for the investigation of human tissue. Industrial process monitoring uses a Raman spectroscopic probe for online quality control during manufacture. 

Information concerning the coordination geometry and dynamics of metal-binding sites in proteins can be obtained from perturbed angular correlation of y-rays (PAC) spectroscopy. The underlying theory of this nuclear spectroscopic method is described in detail in [78] and with special emphasis on biological applications in [79,80]. PAC provides means to determine the nuclear quadrupole interaction at the site of an appropriate nucleus used as a spectroscopic probe. The nuclear quadrupole interactiOTi (NQI) describes the interaction between the electric quadrupole moment... 

In a collaborative effort with many research laboratories, we develop the basic principles of P chemical shifts, coupling constants, and relaxation parameters and then apply these spectroscopic probes to increasingly more complex molecular and biological systems. The chapters have been written by experts in various research areas of phosphorus NMR. The literature has been exhaustively surveyed from the earliest beginnings of phosphorus NMR in the late 1950s to the end of 1982. However, because of the tremendous expansion of the literature in this field, the presentation is selective, and much of the discussion is based on the more recent literature. 

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