Kito-10 Thiolated Chitosan available from PolySciTech: Akina, Inc.
The Polyscitech division of
Akina, Inc. (www.polyscitech.com) now
provides thiolated chitosan as an iminothiolane conjugate (Kitopure: Kito-10).
This pH sensitive and bioadhesive polysaccharide has loose thiol units
available which can form disulfide bonds under appropriate conditions thereby
creating a gel for drug delivery or cell-scaffolding applications.
Additionally, this polymer improves bioavailability. Read more about this class
of polymers here: Sreenivas, S. A., and K. V. Pai. "Thiolated chitosans:
novel polymers for mucoadhesive drug delivery–a review." Tropical Journal
of Pharmaceutical Research 7, no. 3 (2008): 1077-1088. http://www.ajol.info/index.php/tjpr/article/view/14694
“Abstract: Chitosan
is a natural polycationic copolymer consisting of glucosamine and
N-acetylglucosamine units. The polymer has valuable properties as a biomaterial
because it is considered to be biocompatible, biodegradable and non-toxic. The
purpose of this review article is to provide detailed information about
thiolated chitosans which are gaining popularity because of their high
mucoadhsiveness and extended drug release properties. The derivatization of the
primary amino groups of chitosan with coupling reagents bearing thiol functions
leads to the formation of thiolated chitosans. Various properties of chitosan
are improved by the immobilization of thiol groups. Due to the formation of
disulfide bonds with mucus glycoproteins, mucoadhesiveness is augmented. The permeation
of paracellular markers through mucosa can be enhanced by utilizing thiolated
instead of unmodified chitosan. Moreover, thiolated chitosans display in situ
gelling features due to the pH-dependent formation of inter- as well as
intra-molecular disulfide bonds. This latter process provides, strong cohesion
and stability of carrier matrices, being based on thiolated chitosans. The in
situ gel formation within the pH range of 5 to 6.8 makes the application of
thiolated chitosans on vaginal, nasal and ocular mucosa also possible.
Thiolated chitosans can guarantee prolonged controlled release of embedded
therapeutic ingredients. Keywords: Thiolated chitosan,Thiomers, Mucoadhesion,
Permeation enhancement, In situ gelation”
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