Particle size distribution, protein

Petanate, A.M. and Glatz, C.E., 1983. Isoelectric precipitation of soy protein. I. Factors affecting particle size distributions. II. Kinetics of protein aggregate growth and breakage. Biotechnology and Bioengineering, 25, 3049. 

Resin evaluation of both new and used resins (titration of total binding sites, total protein capacity, flow vs. pressure, particle size distribution, total organic carbon removed by cleaning procedures, and microbial and endotoxin analysis)... 

The bar charts in Figs. 27.5 and 27.6 illustrate particle size distribution before and after samples centrifugation. After centrifugation an average size of silver particles in the samples, containing 10, 15 and 50 pg/ml of protein A, is close to 5-8 nm. In the samples, containing protein in concentrations 70 or 100 pg/ml the prevailing Ag particle size is 2-3 nm. The results of electrochemical assay demonstrate that the... 

Protease-resistant isoform of a host-encoded protein Particle size distribution analyser... 

The range of the (molecular) size of the analytes usually exceeds that which can be determined by classical laboratory analytical methods such as size exclusion chromatography, etc. [351]. Reports on investigated substances are widespread and cover applications such as the separation and characterization of proteins [450] and enzymes [240, 241], of viruses [132], the separation of human and animal cells [50, 51], the isolation of plasmid DNA [367], and the molecular weight and particle size distribution of polymers [216,217]. The approach is relatively new in biotechnology therefore, practical experiences are not yet abundant. Langwost et al. [229] have provided a comprehensive survey of various applications in bio-monitoring. 

It is claimed that commercially-available ultrasound equipment can measure the following quality parameters of dairy products levels of solids, solids non-fat (SNF), protein, water and fat solid fat content (SFC), colloidal stability, gelation point, adulteration with oil, particle size, particle size distribution, oil composition, protein denaturation and fat oxidation. This incomplete list represents an impressive contribution towards the solution of food quality measurement although the present authors are slightly skeptical regarding some of these claims. In this review only those applications will be addressed which are regarded as robust. 

Production and processing will determine the properties of particles and powder, such as particle size distribution, shape, surface properties and moisture content. They will also influence ingredient functionality, for example, higher temperatures may cause denaturation of proteins and coating may prevent the ingredient functionality from being destroyed by oxidation. 

Athalye AM, Gibbs SJ, and Lightfoot EN. Predictability of chromatographic protein separations Study of size-exclusion media with narrow particle size distributions. J. Chromatogr. A 1992 589 71-85. 

Mass Transfer Properties. The particle size distribution of Interest In medical devices Is extremely wide, ranging from urea and electrolytes (<1 nm diameter) In hemodialysis to platelets and red cells (3 to 8 ym diameter) In plasmapheresis. Between these extremes, molecular size ranges can be defined that roughly delineate filters suitable for hemodialysis and hemofiltration (that Is, Impermeable to albumin), protein separation (that Is, albumin permeable, IgM Impermeable) and microfiltration (that Is, retentive to platelets and red cells). The lower end of these size distributions Is Indicated In Figure 1. 

Fisher, R. R. 1987. Protein precipitation with acids and polyelectrolytes The effects of reactor conditions and models of the particle size distribution. Ph.D. Thesis. Iowa State University, 165 pp. 

Note The validity of Eq. (5.11) may be questioned for such a strongly bimodal particle size distribution. Another approach is first to calculate the viscosity of the protein solution (with q> — 0.4 and /rel — 4.7. Subsequently, this value is taken for rjs in Eq. (5.11) for the emulsion (with tp = 0.5 and [Pg.122]

The particles may be inhomogeneous. They may be hollow or have a more intricate internal structure. If the inhomogeneity varies among particles, a particle size distribution is insufficient to characterize the dispersion. For instance, the mass average diameter and the volume average diameter may be markedly different this is illustrated by several spray-dried powders, where some of the particles have large vacuoles, while others have not. If the oil droplets in an emulsion are coated with a thick layer of protein, the smallest droplets contain far more protein per unit amount of oil than the largest ones, as illustrated in Table 9.3. 

Figure 4.15 Particle size distribution of protein aggregate in a continuous stirred-tank reactor comparison of model with experimental data. 0.15kg/m A, 300kg/m O, 25.00kg/m. [From The Formation and Growth of Protein Precipitates in a Continuous Stirred-Tank Reactor, C.E. Glatz, M. Hoare, and J. Landa-Vertiz (1987), AIChE J. 32(7), pp. 1196-1204. Reproduced by permission of the American Institute of Chemical Engineers. 1987 AIChE.]...

Precipitation Simple and convenient operation high yield Poor particle size control irregular-shaped particles broad size distribution protein denaturation difficult to handle multicomponents... 

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