dc.contributor.author |
Nadia, Rasool |
|
dc.date.accessioned |
2017-12-04T07:35:09Z |
|
dc.date.accessioned |
2020-04-15T03:54:19Z |
|
dc.date.available |
2020-04-15T03:54:19Z |
|
dc.date.issued |
2013 |
|
dc.identifier.uri |
http://142.54.178.187:9060/xmlui/handle/123456789/11664 |
|
dc.description.abstract |
A novel method was developed to synthesize switchable pH responsive hydrogel
from natural and synthetic polymers. Blends of CM-chitosan and carrageenan were
reacted with acrylic acid and in situ crosslinked with vinyltriethoxy silane (VTESi). This
crosslinker is used for the first time for this type of blends. Three sets of polymeric
hydrogels were prepared in this work. Polymerization steps involve initiation,
propagation, copolymerization and crosslinking reactions. During the process of
polymerization, peroxide was broken into radicals, which attack other molecules and
monomers present in the reactor to convert them into radicals. These resultant radicals
combine with each other to produce stable molecules which upon crosslinking through a
process of condensation lead to the formation of network structure having hydrogels
properties. These hydrogels are then characterized by using various techniques.
Structural and thermal analysis confirmed the presence of crosslinking within hydrogel.
Dynamics of water vapor sorption was also done to show the extent and rate of
vapor uptake of prepared hydrogels. Similarly swelling study in water gave a clear
picture about the effect of concentration of monomer and crosslinking agent on swelling
ability of hydrogel. Swellings in buffered, non-buffered and ionic environment exhibited
a variety of behavior. Temperature was found to be favorable for swelling but only to a
specific extent.
All the developed hydrogels showed switchable response against change in pH of
the external media. These hydrogel showed low swelling at low and high pH and
maximum swelling was observed at neutral pH. This pH response and biocompatible
nature of the incorporated component made it a good candidate for drug delivery
application. These hydrogels were loaded with insulin and its in-vitro release study
showed very interesting results. A very low release of insulin was observed at low pH
and consistent release was observed at neutral pH. Further studies on these systems will
provide another biotechnological material for gastrointestinal delivery for drugs. |
en_US |
dc.description.sponsorship |
Higher Education Commission, Pakistan. |
en_US |
dc.language.iso |
en |
en_US |
dc.publisher |
Quaid-i-Azam University Islamabad, Pakistan |
en_US |
dc.subject |
Natural Sciences |
en_US |
dc.title |
STUDY OF POLYMERIC HYDROGELS AS NOVEL BIOTECHNOLOGICAL MATERIALS |
en_US |
dc.type |
Thesis |
en_US |