title: Sol-gel materials as efficient enzyme protectors: preserving the activity of phosphatases under extreme ph conditions.
abstract: By entrapment in (surfactant modified) silica sol-gel matrixes, alkaline phosphatase (AlP) -- naturally with optimum activity at pH 9.5 -- was kept functioning at extreme acidic environments as low as pH 0.9, and acid phosphatase (AcP) -- naturally with optimum activity at pH 4.5 -- was kept functioning at extreme alkaline environments, up to pH 13.0. Propositions are offered as to the origin of the ability of the matrixes to provide such highly efficient protection and as to the origin of the synergetic enhancing effect when both the silica and the surfactants are used as a combined entrapping environment. It was found that the protectability of the enzymes against harsh pH values is dependent on the nature of the surfactant.
authors.affiliation: Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: Hagit
authors.initials: H
authors.lastname: Frenkel-Mullerad
authors.forename: David
authors.initials: D
authors.lastname: Avnir
mesh_terms: D000135:Acid Phosphatase / Q000737:chemistry* / Q000378:metabolism*; D000469:Alkaline Phosphatase / Q000737:chemistry* / Q000378:metabolism*; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D004143:Dioctyl Sulfosuccinic Acid / Q000737:chemistry; D005782:Gels; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D012822:Silicon Dioxide / Q000737:chemistry; D012996:Solutions; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D002593:Cetrimonium Compounds; D005782:Gels; D012996:Solutions; D013501:Surface-Active Agents; D004143:Dioctyl Sulfosuccinic Acid; D012822:Silicon Dioxide; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D000077286:Cetrimonium