Aggregation suppressing additive

Proteins are inherently nnstable and may produce degraded forms which are harmful when used in treatment of human diseases. On the other hand, protein-based therapeutic preparation are the fastest growing ikw drags nnder development. This calls for use of aggregation suppressing additives which rednce risk of instability. Theory of aggregation prevention and practical applications of preventive measnres are broadly discussed in this review. ... 

The 3-pyridinecarboxyaldehyde 58 is highly water soluble, and so the spontaneous cyanide addition to give racemic cyanohydrin cannot be suppressed unless the aqueous pH is lowered below 3.5, which is not tolerated by the enzymes. The only available option is to operate in a 100% organic solvent system. This was recently made possible by the availability of the cross linked enzyme aggregate particles (CLEAs), which can tolerate organic solvents [64]. The individual precipitated protein molecules are chemically bonded to one another through the formation... 

Hyperlayer-DEP-FFF has the advantage of making better use of the parabolic velocity profile of the fluid since flow at different heights in the channel is exploited as in steric-DEP-FFF the particles essentially stay in the layer near the channel wall. In addition, the hyperlayer mode minimizes the adhesion of the particles to the channel wall, which also suppresses the aggregation of cells into pearl-chains. 

The initial decrease of the apparent rate constants is due to the suppression of free ions in the system. Typically a 2- to 5-fold rate reduction is observed which corresponds to 50 to 80% population of free ions in the system (assuming similar reactivities of ions and ion pairs). The addition of larger amounts of salt has two effects. The first one is the entrapment of Lewis acid and reduction of the polymerization rate. The second effect, which increases the concentration of carbocations, is related to the formation of aggregates of anions (e.g., ionic triplets) as found for SnCI4 [39,269]. 

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