title: Enhancing the reusability of endoglucanase-gold nanoparticle bioconjugates by tethering to polyurethane microspheres.
abstract: The synthesis of polyurethane microsphere-gold nanoparticle "core-shell" structures and their use in the immobilization of the enzyme endoglucanase are described. Assembly of gold nanoparticles on the surface of polymer microspheres occurs through interaction of the nitrogens in the polymer with the nanoparticles, thereby precluding the need for modifying the polymer microspheres to enable such nanoparticle binding. Endoglucanse could thereafter be bound to the gold nanoparticles decorating the polyurethane microspheres, leading to a highly stable biocatalyst with excellent reuse characteristics. The immobilized enzyme retains its biocatalytic activity and exhibits improved thermal stability relative to free enzyme in solution. The high surface area of the host gold nanoparticles renders the immobilized enzyme "quasi free", while at the same time retaining advantages of immobilization such as ease of reuse, enhanced temporal and thermal stability, etc.
authors.affiliation: Materials Chemistry, Biochemical Sciences, and Polymer Chemistry Divisions, National Chemical Laboratory, Pune 411 008, India.
authors.forename: Sumant
authors.initials: S
authors.lastname: Phadtare
authors.forename: Santosh
authors.initials: S
authors.lastname: Vyas
authors.forename: Dnyaneshwar V
authors.initials: DV
authors.lastname: Palaskar
authors.forename: Anil
authors.initials: A
authors.lastname: Lachke
authors.forename: Parshuram G
authors.initials: PG
authors.lastname: Shukla
authors.forename: Swaminathan
authors.initials: S
authors.lastname: Sivaram
authors.forename: Murali
authors.initials: M
authors.lastname: Sastry
mesh_terms: D000327:Adsorption; D002384:Catalysis; D002480:Cellulase / Q000737:chemistry* / Q000648:ultrastructure*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D004789:Enzyme Activation; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D017743:Equipment Reuse; D006046:Gold / Q000737:chemistry*; D008422:Materials Testing; D008863:Microspheres; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011140:Polyurethanes / Q000737:chemistry*; D011485:Protein Binding
chemical_list: D020099:Coated Materials, Biocompatible; D004800:Enzymes, Immobilized; D011140:Polyurethanes; D006046:Gold; D002480:Cellulase