Competitive binding assays utilizing concanavalin A (ConA) have the potential to be the basis of improved continuous glucose monitoring devices. However, the efficacy and lifetime of these assays have been limited, in part, by ConA's instability due to its thermal denaturation in the physiological environment (37 °C, pH 7.4, 0.15 M NaCl) and its electrostatic interaction with charged molecules ...

While an effective non-viral gene carrier, 25 kDa branched polyethylenimine (PEI) is cytotoxic, and decreasing its toxicity while maintaining its functionality is vital. Conjugation of carriers with polyethylene glycol (PEG) is a common approach to decreasing toxicity and improving biodistribution; however, the effect of PEGylation on PEI transfection efficacy is contradictory at present. The a...

The practice of covalent coupling of poly(ethylene glycol) to pharmaceutical proteins, commonly named PEGylation, is now regarded as an extremely useful procedure to overcome certain problems faced in the development and use of protein drugs. The continuing interest in PEGylation is well documented by the number of papers and patents that have appeared since the discovery of this methodology by...

Polyethylene glycol (PEG) was genetically incorporated into a polypeptide. Stop-anticodon-containing tRNAs were acylated with PEG-containing amino acids and were then translated into polypeptides corresponding to DNA sequences containing the stop codons. The molecular weights of the PEG used were 170, 500, 700, 1000, and 2000 Da, and the translation was confirmed by mass spectrometry. The PEG i...

The effect of NAb’s and glycosylation/PEGylation for the pharmacodynamics and pharmacokinetics of IFN-beta have been reviewed with more recent developments. The issue of both NAb’s and glycoslation with current pharmacokinetics in particular, and the issues with current models of NAb’s highlighted. This case study shows how the latest research particularly PEGylation can significantly improve t...

Currently, there are more than 35 US FDA-approved NPs utilizing PEG in their biomedical applications. PEGylation, which is the addition of PEG to the NP formulation, provides immunity from the hostile biological environment. The ‘stealth’ property, further confers on the PEG-NP formulation benefits that are not normally provided by other polymers. This mini-review briefly describes the mechanis...

This study evaluates the influence of particle size, PEGylation, and surface coating on the quantitative biodistribution of near-infrared-emitting quantum dots (QDs) in mice. Polymer- or peptide-coated 64Cu-labeled QDs 2 or 12 nm in diameter, with or without polyethylene glycol (PEG) of molecular weight 2000, are studied by serial micropositron emission tomography imaging and region-of-interest...

Enzymatic approaches of protein PEGylation are widening their applications thanks to the advantageous obtainment of homogeneous mono-PEGylated isomers. Microbial transglutaminase (mTGase) is an enzyme that, in nature, forms protein cross-linkings between side chains of Gln and Lys residues. For protein PEGylation, mTGase allows site-specific modification with PEG-NH2 at precise glutamines of th...

Proteins that are modified by chemical conjugation require at least two separate purification processes. First the bulk protein is purified, and then after chemical conjugation, a second purification process is required to obtain the modified protein. In an effort to develop new enabling technologies to integrate bioprocessing and protein modification, we describe the use of disulfide-bridging ...

The bacterial plasminogen-activator staphylokinase (Sak) is a promising thrombolytic agent for treating acute myocardial infarction. To effectively reduce the immunogenicity of Sak while maintaining its fibrinolytic activity, site-specific PEGylation was performed in the present study. The chemoselective cysteine PEGylation site was selected within an immunodominant region (amino acid residues ...