“…The covalent chemical conjugation of biomolecules to hydrophilic polymers (PEG) by PEGylation is a widely used technology to provide a slow release of biotherapeutic drugs over time. In PEGylation, the linker-functionalized PEG polymer conjugated with the reactive side chains of proteins or peptides ( Pak and Finn, 2013 ). PEGylated proteins have gained increased interest owing to the decreased immunogenicity, low dose frequency and longer circulation half-life compared to the non-pegylated proteins.…”