Lysozyme formulation

Figure 11 Release kinetics of enzymes released from ATRIGEL formulations ri.horseradish peroxidase O, trypsin O, lysozyme. Formulations consisted of PLA (inherent viscosity, 0.05), using polyvinylpyrrolidone and calcium phosphate as additives. Formulation solvent was NMP, and the protein load was 5%. Cumulative release profiles were generated in PBS, pH 7.4.

In order to make an effective use of the VB formulation we have to calibrate the relevant parameters using reliable experimental information. The most important task is to obtain the relevant a-. Since the a s represent the energy of forming the different configurations in the gas phase at infinite separation between the given fragments, it is natural to try to obtain them from gas-phase experiments. In the case of the catalytic reaction of lysozyme one can compile the relevant information from the available gas-phase experiments (Table 6.1) and use it to determine the a s. 

TABLE 14.4 Effect of Buffer Formulation the on Recovery of Protein from FFPE Lysozyme Tissue Surrogates... 

Remmele, R. L., Stushoff, Carpenter, J. F. Real-time spectroscopy analysis of lysozyme during Lyophilization structure-hydration behavior and influence of sucrose. American Chemical Society Symposium, Ser. 567 (Formulation and delivery of proteins and peptides) 1994. 1994 American Chemical Society... 

The three hydrolytic enzymes that have been discussed, a-chymo-trypsin, carboxypeptidase A, and lysozyme, cover a wide range of substrate types and mechanistic possibilities. Formulation of principles which might apply to enzymatic catalysis in general is difficult from such a small sampling, but certain features of the enzymatic and model reactions warrant some comment. 

It was emphasized by C. A. Vernon in the initial formulation of the lysozyme mechanism that the electrostatic stabilization of the oxocarbenium ion by Asp-52 is the most important catalytic factor.208 Theoretical calculations suggest that the activation energy for kcat is lowered by 32 kj/mol ( 8 keal/mol) by electrostatic stabilization.221 A high value for this is indicated by experiments show-... 

Sum) or hollow spherical particles (such as sodium chloride, mannitol, or tobramycin sulfate) are formed depending on the compound. Protein powders such as lysozyme or lactate dehydrogenase can also be produced by this process and can be stabilized through the use of sugars, buffers, and surfactant additives in the formulations. Depending on the solute and conditions of drying, the particles are crystalline in some cases and amorphous in others. ° ... 

Liao Y H, Brown M B, Martin G P (2004). Investigation of the stabilization of freeze-dried lysozyme and the physical properties of the formulations. Euro. J. Pharm. Bio-pharm. 58 15-24. 

There have been two different interpretations of the slow dynamics observed in the SD of the lysozyme hydration layer. The first attributes the intermediate time-scales (30 0 ps) to slow water. Bagchi and co-workers employed the dynamic exchange model to relate the observed slow dynamics to the timescale of the fluctuation of water in the hydration layer [11]. In an alternative interpretation. Song et al. used the formulation developed by Song and Marcus that relates the solvation time correlation function to the DR of the medium. They attributed the... 

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