Swelling behavior of a genetically engineered silk-elastinlike protein polymer hydrogel.
The influence of environmental conditions such as pH, temperature, and ionic strength on the equilibrium swelling ratio of physically crosslinked networks of a genetically engineered silk-elastinlike protein-based copolymer (SELP) with an amino acid repeat sequence of [(GVGVP)4GKGVP(GVGVP)3(GAGAGS)4]12 was investigated. The effects of gelation cure time and initial polymer concentration on the equilibrium swelling ratio and soluble fraction of the hydrogels were also studied. It was found that the soluble fraction linearly correlated with the initial polymer concentration at higher gelation times. Soluble fraction results suggest that final hydrogel water content may be controlled by both initial polymer concentration and gelation time. Equilibrium swelling studies demonstrated that these hydrogels are relatively insensitive to environmental changes such as pH, temperature, and ionic strength. Over the concentration range studied, it was found that an increase in gelation time at 37 degrees C resulted in lower hydrogel weight equilibrium swelling ratios, which corresponds to less soluble polymer released post-gelation. Together, these results have implications for the controlled delivery of bioactive agents from silk-elastinlike hydrogels.
Dinerman
Adam A
AA
Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 N. Pine Street, Baltimore, MD 21201, USA.
Cappello
Joseph
J
Ghandehari
Hamidreza
H
Hoag
Stephen W
SW
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D001704:Biopolymers; D004549:Elastin / Q000737:chemistry* / Q000235:genetics; D005349:Fibroins; D005353:Fibronectins; D005818:Genetic Engineering; D020100:Hydrogels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011108:Polymers / Q000737:chemistry*; D011993:Recombinant Fusion Proteins; D047011:Silk; D012995:Solubility; D013223:Statistics as Topic; D013696:Temperature; D013997:Time Factors
D001426:Bacterial Proteins; D001704:Biopolymers; D005353:Fibronectins; D020100:Hydrogels; D011108:Polymers; D011993:Recombinant Fusion Proteins; D047011:Silk; C089172:silk-like protein polymer; D004549:Elastin; D005349:Fibroins