Characterization of polymeric cocrystals
Abstract
Many challenges arise during the development of new drug carriers. The carrier must meet safety, solubility, and controlled release requirements. Synthetic polymers are being used for delivering drugs, but the possibility of side effects imposes restrictions on acceptable doses of such materials. In order to overcome this limitation, a new drug carrier system that is safe to handle and has virtually no side effects is very much in need. In this regard, naturally available biopolymers serve as potential alternatives. Though several studies concerning natural bio-macromolecules are currently available, there is one serious drawback as many of them are not sufficiently stable during the drug delivery process. Thus, a biopolymer system having a stable crystal structure/network would be a favorable choice. This work details the use of sodium iota-carrageenan fibers as feasible drug carriers. The carrageenan network consists of three-fold double helices having a rigid core structure. In addition, there are pockets of free space around 5 – 8 Å in between a pair of helices that can be utilized to entrap small drug molecules. X-ray fiber diffraction analyses have demonstrated the crystalline nature of the fibers even after incorporating the drug molecule in the carrageenan network. Further, the study has revealed altered unit cell parameters for the complexes suggesting the co-crystallization of the drug molecule in the carrageenan lattice. Modulated differential scanning calorimetry results showed the ability of the polysaccharide network to protect the host drug molecule from thermal deterioration. In the case of high melting point drugs the cocrystals display a decreased temperature at which the drugs melt bringing the potential benefit of increased aqueous solubility for poorly soluble drug molecules. Rheological data indicated significant differences among the cocrystals upon re-hydration and solubilization. The drug release profile from the cocrytal matrix indicated the potential for utilization of the iota-carrageenan fibers as controlled delivery vehicles. Overall, the present research demonstrates the development of a novel drugs carrier using a GRAS excipient that is an inexpensive and non-toxic food hydrocolloid.
Degree
M.S.A.B.E.
Advisors
Janaswamy, Purdue University.
Subject Area
Food Science|Agricultural engineering
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