|
Abstract: PEGylation is an important application
of polyethylene glycol (PEG), a highly investigated
polymer. It involves the covalent attachment of PEG to
drugs to solve many tribulations associated with
proteinous and non-proteinous drugs. A stable bond is
formed between PEG polymer and drug of choice.
PEGylation is necessary for the reasons such as
increasing the solubility, stability, circulation
half-life, for minimizing the rapid kidney clearance,
for achieving the controlled release, etc. Advanced
PEGylation overcomes the drawbacks of the earlier
technology. Four types of bioconjugates of PEG comprise
conjugation with peptides and proteins, with lipids,
with low molecular weight drugs and with biological
macromolecules. PEGylation is widely applied in various
fields viz. medical, diagnostic, synthesis of peptides
and carrying out some organic synthetic reactions.
Introduction
PEG is a highly investigated polymer and finds its many
applications for pharmaceutical purposes. One of the
very interesting applications in drug profile
modification is PEGylation. It involves the covalent
attachment of PEG to drugs to solve many issues faced by
protein and nonprotein drugs. PEGylation was first
described in the 1970’s by Davies and Abuchowsky and
reported in two key papers on albumin and catalase
modification.
Properties of PEG
Polyethylene glycol has the general formula
HO-(CH2-CH2-O) n–CH2-OH with the typical molecular
weight ranging into 500-20000. PEG is nontoxic,3
non-immunogenic or poorly immunogenic. It can be used to
precipitate proteins and nucleic acids. It forms
two-phase system with an aqueous solution of other
macromolecules, such as dextran or concentrated salt
solutions. PEG’s covalent coupling with proteins,
peptides exhibit following properties: Renders protein
non-immunogenic and tolerogenic, prolongs the clearance
time in vivo when conjugated with drugs, it alters the
pharmacokinetics of various drugs, stabilize the
physiological function of proteins and bioactive
substances, separates biological macromolecules,
membranes, cell particles.
What is Pegylation?
PEGylation is the technique that involves the
modification of a protein, peptide or nonpeptide
molecule (drug) by covalent attachment of one or more
PEG molecules for the purpose of enhancing therapeutic
value. Advanced PEGylation10 involves attaching
specific, modified polyethylene glycol (PEG) polymers to
biomolecules. The difference between old PEGylation and
new or advanced PEGylation are summarized in the Table
1.
For full text of this article contact the publisher on
info@kppub.com
|
The above content is an
abstract only. For the full Article please contact:
KONGPOSH Publications Pvt. Ltd.
ICS House, C-19, Commercial Complex, SDA, Opp. IIT Gate,
New Delhi, India -110016
Tel.: 26855839, 20057149, Fax: 91-11-26855876
Email:
info@kppub.com /
fpc@vsnl.com, Website:
http://www.kppub.com |
