PMC:2812708 / 1455-3869 JSONTXT

{"project":"MyTest","denotations":[{"id":"19242689-15043928-28778234","span":{"begin":1130,"end":1134},"obj":"15043928"},{"id":"19242689-19816525-28778235","span":{"begin":1699,"end":1703},"obj":"19816525"},{"id":"19242689-19816525-28778236","span":{"begin":2265,"end":2269},"obj":"19816525"},{"id":"19242689-19816525-28778237","span":{"begin":2408,"end":2412},"obj":"19816525"}],"namespaces":[{"prefix":"_base","uri":"https://www.uniprot.org/uniprot/testbase"},{"prefix":"UniProtKB","uri":"https://www.uniprot.org/uniprot/"},{"prefix":"uniprot","uri":"https://www.uniprot.org/uniprotkb/"}],"text":"Analytical Ultracentrifugation is an analytical absolute technique applying centrifugal force to fractionate the sample and optical detection systems to detect the concentration distribution of the sample inside the ultracentrifuge cell. These experiments yield a number of important physico-chemical quantities of the sample like size, shape, density, molar mass, sedimentation and diffusion coefficient, interaction constants and stoichiometry etc. and many of them in form of distributions. However, often the available information depends on the applied optical detection system. Optical systems that have been constructed are UV/vis absorption, Rayleigh interference, Schlieren and the Lavrenko Optics (Lavrenko et al. 1999; Lloyd 1974). Development of new optical detection systems can expand the possible use of AUC for different types of samples. Size distributions can be determined with Turbidity optics (Mächtle 1992; Müller 1989; Scholtan and Lange 1972). Fluorescence optics has expanded the use for extremely diluted labeled samples even in presence of other solutes at a much higher concentration (MacGregor et al. 2004; Schmidt and Riesner 1992). The only commercially available machine at the moment is the Beckman XL-I which is equipped with a UV/vis absorption optics and Rayleigh interference optics (Giebeler 1992). Recently, the UV/vis absorption detection was significantly improved by the development of a multiwavelength UV/vis absorption detector (MWL-AUC). By essentially replacing the monochromator with a spectrograph, the MWL-AUC delivers an entire UV/vis spectrum for each radial point instead of a single wavelength reading (Bhattacharyya et al. 2006; Strauss et al. 2008). This technology has a number of advantages over the commercial absorption optics detecting at a single wavelength with time-consuming wavelength scanning, thus excluding the study of all fast processes, Obtaining full UV/vis spectra at each point in the ultracentrifuge cell rather than a radial concentration profile at a single wavelength can give much more structural information about the sample, allows for averaging and can even decrease the experimental time when modern fast CCD based spectrometers are used (Bhattacharyya et al. 2006; Strauss et al. 2008). Successful optical, mechanical, radial scan, linearity and noise tests of the MWL detector have been published recently (Strauss et al. 2008)."}

{"project":"2_test","denotations":[{"id":"19242689-15043928-28778234","span":{"begin":1130,"end":1134},"obj":"15043928"},{"id":"19242689-19816525-28778235","span":{"begin":1699,"end":1703},"obj":"19816525"},{"id":"19242689-19816525-28778236","span":{"begin":2265,"end":2269},"obj":"19816525"},{"id":"19242689-19816525-28778237","span":{"begin":2408,"end":2412},"obj":"19816525"}],"text":"Analytical Ultracentrifugation is an analytical absolute technique applying centrifugal force to fractionate the sample and optical detection systems to detect the concentration distribution of the sample inside the ultracentrifuge cell. These experiments yield a number of important physico-chemical quantities of the sample like size, shape, density, molar mass, sedimentation and diffusion coefficient, interaction constants and stoichiometry etc. and many of them in form of distributions. However, often the available information depends on the applied optical detection system. Optical systems that have been constructed are UV/vis absorption, Rayleigh interference, Schlieren and the Lavrenko Optics (Lavrenko et al. 1999; Lloyd 1974). Development of new optical detection systems can expand the possible use of AUC for different types of samples. Size distributions can be determined with Turbidity optics (Mächtle 1992; Müller 1989; Scholtan and Lange 1972). Fluorescence optics has expanded the use for extremely diluted labeled samples even in presence of other solutes at a much higher concentration (MacGregor et al. 2004; Schmidt and Riesner 1992). The only commercially available machine at the moment is the Beckman XL-I which is equipped with a UV/vis absorption optics and Rayleigh interference optics (Giebeler 1992). Recently, the UV/vis absorption detection was significantly improved by the development of a multiwavelength UV/vis absorption detector (MWL-AUC). By essentially replacing the monochromator with a spectrograph, the MWL-AUC delivers an entire UV/vis spectrum for each radial point instead of a single wavelength reading (Bhattacharyya et al. 2006; Strauss et al. 2008). This technology has a number of advantages over the commercial absorption optics detecting at a single wavelength with time-consuming wavelength scanning, thus excluding the study of all fast processes, Obtaining full UV/vis spectra at each point in the ultracentrifuge cell rather than a radial concentration profile at a single wavelength can give much more structural information about the sample, allows for averaging and can even decrease the experimental time when modern fast CCD based spectrometers are used (Bhattacharyya et al. 2006; Strauss et al. 2008). Successful optical, mechanical, radial scan, linearity and noise tests of the MWL detector have been published recently (Strauss et al. 2008)."}