Kinetic release

The complex decays with first-order kinetics, releasing the enzyme to act again ... 

With respect to the considerations above, research is split into three parts. The first is connected to the kinetic description of the release of ammonia from the biomass as function of temperature. This research employs infrared spectroscopy using a tunable diode laser. Here very small biomass particles are used that are heated up very rapidly in a small reactor, which ensures that transport effects are virtually excluded from the kinetic release effects. Since ammonia is released in very small quantities it is quite hard to detect. Therefore, we first measure CO release, which is easier. In the second part we investigate the propagation of a conversion front in biomass layers. Here we perform experiments and try to establish a modeling approach for the propagation by analytical and numerical approaches. In the third part the gas-phase conversion processes are described in terms of... 

Connaughton DF, Stedinger JR, Lion LW, Shuler ML (1993) Description of time varying desorption kinetics release of naphthalene from contaminated soils. Environ Sci Technol 27 2397... 

Soo et al. (2002) studied tliB vitro release of hydrophobic Luorescent probes from PEO-b PCL micelles. Micelle solutions were placed in dialysis bags (MWCO 50,000) in a stirred water bath with a constant overLow of distilled water. This maintained the release environment at near perfect sink conditions, so the limited solubility ofthe probes in the medium did not affect release kinetics. Release was determined by removing aliquots ofthe dialysis bag contents and measuring Luorescently. Soo et al. found an initial burst release of probe followed by slow diffusional release. For the probes studies, benzopyrene and Cell-Tracker-CM-Dil, diffusion constants were ofthe order 10"15 cnnP/s. 

As previously indicated, intraocular sustained-release delivery systems are of two types. In matrix systems, the drug is homogeneously dispersed inside the matrix material, and slow diffusion of the drug through the polymatrix material provides sustained release of the drug. The kinetic release of drug in matrix systems is not... 

Fig. 22.6 a Dissolution curves of free ATV and loaded ATY into different mesoporous structures (simulated Intestine fluid, SIF, performed under sink conditions), b Kinetic release curve of different particles to SIF ratio. Varied amount of NFM-l-ATV was added into 500mL SIF, respectively, corresponding to a series of particles-to-SlF ratio 20, 40, 80 and 160mg/L. c ATV plasma concentration, Sprague Dawley rats were administered with Omeprazole (lOOmg/kg) 8 h prior to the administration of free atazanavir and NFM-1 Silica loaded with atazanavir (lOmg/Kg)... 

M.G. Albu, M.V. Ghica, A. Ficai, I. Titorencu, and L.Popa, The influence of freeze drying process on porosity and kinetics release of collagen-doxycychne matrices. Proceedings of 3rd International Conference on Advanced Materials and Systems, ISBN 2068-0783, Bucharest, Romania, Sept, 2010. 

The results of this study indicate that cell transfection, with subsequent amperometric detection of exocytosis, allows valid and efficient analysis of the roles of specific proteins on the quantitative and kinetic release aspects of individual exocytotic events. Studies utilizing this combined methodology, therefore, hold the potential to provide a powerful tool for the future analysis of other components of the exocytotic machinery. 

However, the first reaction can be distinguished from the dissociative ionization processes because its TOP peak is expected to be narrow, whereas the latter two reactions will impart kinetic energy to their fragments and thus result in broadened TOP peaks. This is illustrated in Pigure 4. The narrow peak with a width of 34 ns is due to reaction [18], while the broad peak with a width of 160 ns is due to the dissociative processes. By this approach, an onset of 13.03 eV for the ArCO" ion from ArCO could be measured. In addition, by measuring the width of the broad peak as a function of the cluster ion energy, it was possible to extrapolate the kinetic release in the second reaction down to the threshold (as shown in Pigure 5). 

Jimenez-Kairuz, A.F., Allemandi, D.A., Manzo, R.H. Equilibrium properties and mechanism of kinetic release of metoclopramide from carbomer hydrogels. Int. J. Pharm. 250(1), 129-136 (2003)... 

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