Protein release kinetics additive effects

Nevertheless, it has been proved that the addition of PEG to the system produces a reduction of encapsulation efficiency for drugs and proteins, even when the appropriate fabrication technique is used. That reduced drug inclusion could be related to steric interference of drug/protein-polymer interaction by the PEG chains, but until now, the precise mechanism for this effect was not elucidated. Improved release kinetics... 

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