Homogenization time

Homogeneous Time Resolved Fluorescence (HTRF) (Cisbio International) is an assay based on the proximity of a lanthanide cryptate donor and a fluorescent acceptor molecule whose excitation wavelength overlaps that of the cryptate s emission. The utility of this technique is based on the time resolved fluorescence properties of lanthanides. Lanthanides are unique in the increased lifetime of their fluorescence decay relative to other atoms, so a delay in collection of the emission intensity removes the background from other fluorescent molecules. An example of the HTRF assay is a generic protein-protein interaction assay shown in Fig. 2. 

Cencic, R., Yan, Y., and Pelletier, J. (2007). Homogenous time resolved fluorescence assay to identify modulators of cap-dependent translation initiation. Comb. Chem. High Throughput Screen 10, 181-188. 

Blomberg, K., Hurskainen, P. and Hemmila, I. (1999). Terbium and rhodamine as labels in a homogeneous time-resolved fluorometric energy transfer assay of the b-subunit of human chorionic gonadotropin in serum. Clin. Chem. 45, 855-61. 

Maurel, D., Kniazeff, J., Mathis, G., Trinquet, E., Pin, J. P. and Ansanay, FI. (2004). Cell surface detection of membrane protein interaction with homogeneous time-resolved fluorescence resonance energy transfer technology. Anal. Biochem. 329, 253-62. 

Liang, A.M., Claret, E., Ouled-Diaf, J., Jean, A., Vogel, D., Light, D.R., Jones, S.W., Guilford, W.J., Parkinson, J.F., and Snider, R.M. (2007) Development of a homogeneous time-resolved fluorescence leukotriene B4 assay for determining the activity of Leukotriene A4 hydrolase. J. Biomol. Screen. 12, 536-545. 

Show that the volumetric average velocity u of a homogeneous, time-independent liquid in laminar flow through a straight pipe can be written as... 

The dispersion of this waiting time distribution, i.e., its second central moment, is a measure that we can use to define a homogenization time scale on which the dispersion is equal to that of a homogeneous (Poisson) system on a time scale given by the torsional autocorrelation time. The homogenization time scale shows a clear non-Arrhenius temperature dependence and is comparable with the time scale for dielectric relaxation at low temperatures.156... 

L Hemmila, O. Malminen, H. Mikola, and T. Lovgren, Homogeneous time-resolved fluoroimmu-noassay of thyroxin in serum, Clin. Chem. 34, 2320-2322 (1988). 

HTRF (homogeneous time-resolved fluorescence) LANCE (lanthanide chelate excitation) Cisbio International PerkinElmer Life Sciences Lanthanide TR-FRET using Eu3+ cryptate/chelate-donor fluorophore and cross-linked aUophycocyanin-acceptor fluorophore... 

Kolb, A.J., Burke, J.W., and Mathis, G., Homogeneous, time-resolved fluorescence method for drug discovery, in High Throughput Screening, The Discovery of Bioactive Substances, Devlin, J.P., Ed., Marcel Dekker, New York, 1997, chap. 19. 

Homogenization time and residence time of a zoned crystal in the magma chamber... 

For a mineral with oscillatory zoning (such as plagioclase), the homogenization time (reduction of initial amplitude by a factor of 100) may be estimated from... 

In this simplified version of the Brusselator model, the trimolecular autocatalytic step, which is a necessary condition for the existence of instabilities, is, of course, retained. However, the linear source-sink reaction steps A—>X—>E are suppressed. A continuous flow of X inside the system may still be ensured through the values maintained at the boundaries. The price of this simplification is that (36) can never lead to a homogeneous time-periodic solution. The homogeneous steady states are... 

Robustness. Examples of typical possible sources of variation in automated methods are homogenization speed, homogenization time, age of sample, accuracy of solvent dispense, and temperature variation. If all studies described in the method development have been performed, the robustness of the sample preparation has been demonstrated and does not require additional testing. Parameters in relation to the measurement technique may need to be considered and are covered in the relevant chapter. 

Wang, G., J. Yuan, K. Matsumoto, et al. 2001. Homogeneous time-resolved fluoroimmunoassay of bensulfuron-methyl by using terbium fluorescence energy transfer. Talanta 55 1119-1125. 

Fig. 13. Structure of TBP-Eu3+ and principle of TRACE homogeneous time-resolved fluoroimmunoassays.

Homogenization characteristics of a mechanically agitated polymerization reactor in terms of NO = /(Reeff = Ndfp/pe( ) have been published for various stirrer types and pseudoplastic liquids with power-law behavior (Opara, 1975, Tebel et al, 1986). The homogenization time is compared to that for Newtonian fluids (Opara, 1975), and the homogenization properties of a... 

Ferrer, M. et al. 2003 Miniaturizable homogeneous time-resolved fluorescence assay for carboxypeptidase B activity. Anal. Biochem. 317. 94-98. 

Karvinen, J. et al. 2002. Homogeneous time-resolved fluorescence quenching assay (LANCE) for caspase 3. J. Biomol. Screen. 1, 223-231. 

Primary Homogeneous Time-Resolved Fluorescence (HTRF) HTS Assay.84... 

PRIMARY HOMOGENEOUS TIME-RESOLVED FLUORESCENCE (HTRF) HTS ASSAY... 

Inherent fluorescence in natural product samples rules out the use of frank fluorescence as an assay readout. In the early 1990s, the development of homogeneous time-resolved fluorescence (HTRF) allowed the use of fluorescence with such samples (Kolb, Yamanaka, and Manly, 1996 Kolb and Manly, 1997 Bazin, Trinquet, and Mathis, 2002 Mathis, 1999). This technique... 

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