Biomedical Engineering Reference
In-Depth Information
Tabl e 2
Examples of drug delivery systems prepared using supercritical fluid impregnation
method
Impregnated bioactive
solute
Impregnated polymer
Application
Reference
Poly(vinylpyrrolidone)
Ibuprofen
Antiinflammatory DDS
[
61
]
Poly(vinylpyrrolidone)
Indomethacin
Improve drug
availability
[
66
]
Chitosan thermosets
Indomethacin
Improve drug
availability
[
67
]
Poly(vinylpyrrolidone)
Ketoprofen
Improve oral
availability
[
68
]
Poly(sebacic anhydride),
Indomethacin
Implant device
[
69
]
Porous methacrylate system
Chlorhexidine
diacetate
Dental materials
[
70
]
Chitosan derivatives
(N-carboxymethyl
chitosan, N-carboxybutyl
chitosan and N-succinyl
chitosan)
Flurbiprofen and
timolol maleate
Ophthalmic DDS
[
44
]
Hydroxypropylmethyl
cellulose
Indomethacin
DDS using highly
water swelled gel
system
[
71
]
Poly(e-caprolactone) blends
Timolol maleate
Ophthalmic DDS
[
63
]
Poly(vinylpyrrolidone)
Piroxicam
Antiinflammatory DDS
[
72
]
Poly(methyl methacrylate)
Triflusal
Implant carrier as
antiinflammatory
DDS
[
73
]
Commercial silicone-based
hydrogel contact lenses
Acetazolamide and
timolol maleate
Ophthalmic DDS
[
64
]
Commercial contact lenses
(nelfilcon A, omafilcon
A, methafilcon A and
hilafilcon B)
Flurbiprofen and
timolol maleate
Ophthalmic DDS
[
65
]
N-carboxybutyl chitosan and
agarose
Quercetin and thymol
Topical wound
dressing
[
45
]
Biopolymer substrate materials were prepared in the shape of films and as foams
in order to understand how their different physical-chemical characteristics may
influence their final loading, release and barrier properties. The advantages of using
chitosan and agarose based biomaterials as support for the wound dressing materials
were previously mentioned and justified. Quercetin and thymol were chosen mainly
due to their important biological activities that can contribute to enhance the wound
healing process as will be described in what follows.
The potential of polyphenols or flavonoids as antioxidant natural based com-
pounds is well studied and demonstrated [
76
-
78
]. All flavonoids have the same
basic chemical structure - a three-ringed molecule with hydroxyl (OH) groups
attached but depending on the type and number of other substitutions more than
4,000 flavonoids, with different activities can be obtained. Quercetin, one of the
