Silk Fibroin as an Organic Polymer for Controlled Drug Delivery

Journal Article · Sun Jan 01 04:00:00 EST 2006 · J. Controlled Release

DOI:https://doi.org/10.1016/j.jconrel.2005.12.009· OSTI ID:914328

Hofmann, S; Wong Po Foo, C; Rossetti, F; Textor, M; Vunjak-Novakovic, G; Kaplan, D; Merkle, H; Meinel, L

The pharmaceutical utility of silk fibroin (SF) materials for drug delivery was investigated. SF films were prepared from aqueous solutions of the fibroin protein polymer and crystallinity was induced and controlled by methanol treatment. Dextrans of different molecular weights, as well as proteins, were physically entrapped into the drug delivery device during processing into films. Drug release kinetics were evaluated as a function of dextran molecular weight, and film crystallinity. Treatment with methanol resulted in an increase in {beta}-sheet structure, an increase in crystallinity and an increase in film surface hydrophobicity determined by FTIR, X-ray and contact angle techniques, respectively. The increase in crystallinity resulted in the sustained release of dextrans of molecular weights ranging from 4 to 40 kDa, whereas for less crystalline films sustained release was confined to the 40 kDa dextran. Protein release from the films was studied with horseradish peroxidase (HRP) and lysozyme (Lys) as model compounds. Enzyme release from the less crystalline films resulted in a biphasic release pattern, characterized by an initial release within the first 36 h, followed by a lag phase and continuous release between days 3 and 11. No initial burst was observed for films with higher crystallinity and subsequent release patterns followed linear kinetics for HRP, or no substantial release for Lys. In conclusion, SF is an interesting polymer for drug delivery of polysaccharides and bioactive proteins due to the controllable level of crystallinity and the ability to process the biomaterial in biocompatible fashion under ambient conditions to avoid damage to labile compounds to be delivered.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 914328
• Report Number(s): BNL--78896-2007-JA
• Journal Information: J. Controlled Release, Journal Name: J. Controlled Release Journal Issue: 1-2 Vol. 111
• Country of Publication: United States
• Language: English

Related Subjects

10 SYNTHETIC FUELS
AQUEOUS SOLUTIONS
DEXTRAN
DRUGS
ENZYMES
KINETICS
LYSOZYME
METHANOL
MOLECULAR WEIGHT
ORGANIC POLYMERS
PEROXIDASES
POLYMERS
POLYSACCHARIDES
PROCESSING
PROTEINS
national synchrotron light source