title: Volume change of double cross-linked poly(aspartic acid) hydrogels induced by cleavage of one of the crosslinks.
abstract: In the present paper we report for the first time the development of redox-responsive biocompatible polymer gels. Double cross-linked poly(aspartic acid) hydrogels were prepared using two different cross-linking agents simultaneously. One of the cross-linkers was diaminobutane (DAB), the other cystamine (CYS). The relative amounts of DAB and CYS molecules were varied over a wide range while the total amount of cross-linker molecules (DAB+CYS) was kept constant. DAB provides stable cross-links, whereas CYS contains disulfide bonds, which can be broken by reduction. The cleavage of disulfide cross-links results in enhanced swelling and a significant decrease in the elastic modulus of the gels. These novel types of stimuli-responsive gels are promising candidates for new swelling controlled release matrices.
authors.affiliation: Department of Biophysics and Radiation Biology, Semmelweis University, Laboratory of Nanochemistry, Nagyvaradter 4, Budapest H-1089, Hungary. mikloszrinyi@gmail.com
authors.forename: Miklos
authors.initials: M
authors.lastname: Zrinyi
authors.forename: Tamas
authors.initials: T
authors.lastname: Gyenes
authors.forename: David
authors.initials: D
authors.lastname: Juriga
authors.forename: Ji-Heung
authors.initials: JH
authors.lastname: Kim
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000737:chemistry; D002073:Butanes / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000737:chemistry*; D003538:Cystamine / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry; D055119:Elastic Modulus; D020100:Hydrogels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D016018:Least-Squares Analysis; D008970:Molecular Weight; D010084:Oxidation-Reduction; D010316:Particle Size; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry*; D012996:Solutions; D017550:Spectroscopy, Fourier Transform Infrared; D013314:Stress, Mechanical; D013816:Thermodynamics; D014783:Viscosity
chemical_list: D002073:Butanes; D003432:Cross-Linking Reagents; D004220:Disulfides; D020100:Hydrogels; D010455:Peptides; D012996:Solutions; C017645:polyaspartate; C025252:poly-DL-succinimide; D001224:Aspartic Acid; C046888:butane; D003538:Cystamine