10 Biomedical Applications of Chitosan
The vast commercial potential for applications using chitin and chitosan
biopolymers has only recently been understood by the scientific community.
Commercial uses for chitin and chitosan for biomedical applications include
pharmaceuticals and other aspects of health care such as wound care products,
medical implants, etc. Applications that take advantage of the biocompatibility and
bioactivity of chitin and chitosan represent the numerous useful applications of
these biopolymers. For instance, chitosan prevents the formation of scar tissue by
inhibiting the formation of fibrin strands in wounds. As a consequence of this
property, chitosan, along with chitin, can be used to form sutures, dressings, and
other healing agents with properties not found in competing products. In addition,
because lysozyme present in wounds breaks down chitin, the need to remove
sutures and wound dressings made of chitin after application is avoided. Further,
the advent of nanotechnology widens the scope for using chitin and chitosan as
wound dressing materials.
Recently, biopolymer-based nanomaterials in the form of microgels, nanogels,
and nanoparticles have received a great deal of interest in tissue engineering
and drug delivery applications [225–227]. The ability of nanoparticles to manipulate
the molecules and their structures has revolutionized the conventional DDS.
Chitosan is an excellent biopolymer for preparation of micro- and nanoparticles
[228]. Chitosan nanoparticles, because of their biodegradability, biocompatibility,
better stability, low toxicity, and simple and mild preparation methods, offer a
valuable tool for developing novel DDSs. Li et al. [229] reported an innovative
smart DDS based on magnetic and fluorescent multifunctional chitosan
nanoparticles, which combined magnetic targeting, fluorescent imaging, and
stimulus-responsive drug release properties into one DDS. Water-soluble superparamagnetic Fe 3 O 4 nanoparticles, CdTe QDs and pharmaceutical drugs were simultaneously incorporated into chitosan nanoparticles by crosslinking the composite
particles with glutaraldehyde. The system showed superparamagnetic and strong
fluorescent properties, and was used as a controlled drug release vehicle, which
showed pH-sensitive drug release for a prolonged period of time. In another study,
Wilson et al. [230] demonstrated tacrine-loaded chitosan nanoparticles prepared by
spontaneous emulsification. The prepared particles showed good drug-loading
capacity. The in vitro release studies showed an initial burst release followed by a
continuous and slow release of the drug. Coating of nanoparticles with Polysorbate
80 slightly reduced the drug release from the nanoparticles. The chitosan
nanoparticles have also been reported to have major applications in parentral drug
delivery, per-oral administration of drugs, nonviral gene delivery, vaccine delivery,
ocular drug delivery, electrodeposition, brain-targeting drug delivery, stability
improvement, mucosal drug delivery, controlled drug delivery of drugs, tissue
engineering and for the effective delivery of insulin [231]. Recently, chitosanbased nanoparticles for oral controlled delivery of insulin and other therapeutic
agents have been reviewed elsewhere [232]. A snapshot of chitosan-based
nanomaterials and their biomedical applications is shown in Table 9.
120
J. Dutta
The vast commercial potential for applications using chitin and chitosan
biopolymers has only recently been understood by the scientific community.
Commercial uses for chitin and chitosan for biomedical applications include
pharmaceuticals and other aspects of health care such as wound care products,
medical implants, etc. Applications that take advantage of the biocompatibility and
bioactivity of chitin and chitosan represent the numerous useful applications of
these biopolymers. For instance, chitosan prevents the formation of scar tissue by
inhibiting the formation of fibrin strands in wounds. As a consequence of this
property, chitosan, along with chitin, can be used to form sutures, dressings, and
other healing agents with properties not found in competing products. In addition,
because lysozyme present in wounds breaks down chitin, the need to remove
sutures and wound dressings made of chitin after application is avoided. Further,
the advent of nanotechnology widens the scope for using chitin and chitosan as
wound dressing materials.
Recently, biopolymer-based nanomaterials in the form of microgels, nanogels,
and nanoparticles have received a great deal of interest in tissue engineering
and drug delivery applications [225–227]. The ability of nanoparticles to manipulate
the molecules and their structures has revolutionized the conventional DDS.
Chitosan is an excellent biopolymer for preparation of micro- and nanoparticles
[228]. Chitosan nanoparticles, because of their biodegradability, biocompatibility,
better stability, low toxicity, and simple and mild preparation methods, offer a
valuable tool for developing novel DDSs. Li et al. [229] reported an innovative
smart DDS based on magnetic and fluorescent multifunctional chitosan
nanoparticles, which combined magnetic targeting, fluorescent imaging, and
stimulus-responsive drug release properties into one DDS. Water-soluble superparamagnetic Fe 3 O 4 nanoparticles, CdTe QDs and pharmaceutical drugs were simultaneously incorporated into chitosan nanoparticles by crosslinking the composite
particles with glutaraldehyde. The system showed superparamagnetic and strong
fluorescent properties, and was used as a controlled drug release vehicle, which
showed pH-sensitive drug release for a prolonged period of time. In another study,
Wilson et al. [230] demonstrated tacrine-loaded chitosan nanoparticles prepared by
spontaneous emulsification. The prepared particles showed good drug-loading
capacity. The in vitro release studies showed an initial burst release followed by a
continuous and slow release of the drug. Coating of nanoparticles with Polysorbate
80 slightly reduced the drug release from the nanoparticles. The chitosan
nanoparticles have also been reported to have major applications in parentral drug
delivery, per-oral administration of drugs, nonviral gene delivery, vaccine delivery,
ocular drug delivery, electrodeposition, brain-targeting drug delivery, stability
improvement, mucosal drug delivery, controlled drug delivery of drugs, tissue
engineering and for the effective delivery of insulin [231]. Recently, chitosanbased nanoparticles for oral controlled delivery of insulin and other therapeutic
agents have been reviewed elsewhere [232]. A snapshot of chitosan-based
nanomaterials and their biomedical applications is shown in Table 9.
120
J. Dutta