Biomedical Engineering Reference
In-Depth Information
and cationic groups can avoid the use of toxic cross-linkers and organic solvents. Ionotropic gela-
tion method using small molecular weight counterions such as sodium tripolyphosphate and sodium
citrate can be employed for the preparation of chitosan particles.
7.4.4.2.5
Thermal Denaturation
A number of water-soluble proteins denature when heated since they are heat-sensitive. The dena-
turation process causes protein chains to unfold and become chemically cross-linked. This property
can be properly modulated to form protein microsphere. BSA microspheres are usually prepared
by this technique.
7.5 CONCLUDING REMARKS
Several promising approaches are being developed to improve the effi cacy of oral peptide-delivery
systems. Polymeric particulate systems undoubtedly have enormous potential toward developing
oral drug-delivery systems. Some of these carriers have been shown effi ciency in improving the bio-
availability of peptides and proteins either by transporting directly through the intestinal epithelium
or by enhancing the permeability of the mucosal barriers. In spite of their advantages and shortcom-
ings, polymeric systems continue to be the most promising systems for developing oral formulations
for therapeutic peptides. However, most of these studies are still in preclinical phase, and more
intense research is required in this direction to make a marketable oral protein formulation.
Another major aspect is that current encapsulation technologies are far from being optimal for a
good manufacturing practice (GMP) environment and for making marketable products at industrial
scale. Therefore, efforts are currently devoted to developing novel technologies of microencapsula-
tion that can be readily scaled up.
More intense and innovative research is required in the area of polymer drug-delivery sys-
tems to render them as a possible solution to the problems associated with protein pharmaceuticals.
A better understanding of the mechanisms of action of these novel vehicles will provide a basis for
their further optimization, thus opening more exciting opportunities for improving the administra-
tion of macromolecules. A positive outcome in this direction will have a direct impact in the society
and may help in alleviating human sufferings to a large extent.
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