RRC ID 67966
Author Casolaro M, Bottari S, Ito Y.
Title Vinyl polymers based on L-histidine residues. Part 2. Swelling and electric behavior of smart poly(ampholyte) hydrogels for biomedical applications.
Journal Biomacromolecules
Abstract Hydrogels based on the uncharged N-isopropylacrylamide and the ionic ampholyte N-acryloyl-L-histidine showed a reversible multiple-responsive volume change and volume phase transition behavior in aqueous solution. The phase transition phenomenon was induced by the temperature, the pH, the salt-type concentration, and the electric potential. The kind of cation (Na+, K+, Cs+, Mg2+, Ca2+, Sr2+) and anion (Cl-, ClO4-, NO3-, SO4(2-)) strongly influenced the critical concentration that improved the phase separation of the gels. The volume of the collapsed gel can be hundred times smaller than that of the swollen one. The oscillatory swelling of the gels in response to temperature and pH (4 and 9) changes was fast and reversible, while the contractile behavior in the electric field showed response only at pH 9, i.e., when the amount of negative charges on the L-histidine residues predominated. The electrically induced anisotropic gel deswelling was attributed to the syneresis of water from the gel. The nontoxicity against the RAW264 cell line and the low osmotic pressure exhibited by the swollen gels make these compounds useful scaffolds for human organs. The ability to load and release an ionizable drug molecular model (ferulic acid) from the hydrogels was shown also at different pH values.
Volume 7(5)
Pages 1439-48
Published 2006-5-1
DOI 10.1021/bm0509671
PMID 16677025
MeSH Acrylamides Biocompatible Materials / chemical synthesis* Biocompatible Materials / chemistry Biopolymers / chemistry* Histidine* / chemical synthesis Histidine* / chemistry Hydrogels* Kinetics Microscopy, Electron, Scanning Molecular Conformation Thermodynamics Vinyl Compounds*
IF 6.092
Human and Animal Cells RAW 264(RCB0535)