title: Fabrication of gold nanoparticle assembled polyurethane microsphere template in trypsin immobilization.
abstract: The separation, reusability and high catalytic activity of bioconjugate remain challenging task in proteins bound gold nanoparticles. A facile synthetic route for the fabrication of gold nanoparticle assembled polyurethane microsphere template and immobilization of trypsin on gold/polyurethane surface to form trypsin-nanogold-polyurethane bioconjugate was developed. The bioconjugate was characterized by X-ray diffraction, Field emission scanning electron microscopy, Transmission electron microscopy, UV-visible, Fourier transform infrared, Fluorescence and Circular dichroism spectroscopy. The catalytic studies confirmed retention of approximately 40% of its original activity even after eight consecutive reaction cycles. The bioconjugate is also very effective for its separation from the reaction medium and exhibited significant enhanced stability over a wide range of pH and temperature compared to free trypsin. These findings clearly demonstrate that trypsin immobilized gold nanoparticle assembled polyurethane microsphere acts as an excellent recyclable biocatalyst with enzyme-specific biocompatibility.
authors.affiliation: Inorganic Materials and Nanocomposite Laboratory, Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India.
authors.forename: Moumita
authors.initials: M
authors.lastname: Kotal
authors.forename: Suneel K
authors.initials: SK
authors.lastname: Srivastava
authors.forename: Tapas K
authors.initials: TK
authors.lastname: Maiti
mesh_terms: D019149:Bioreactors; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D017743:Equipment Reuse; D006046:Gold / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D053768:Metal Nanoparticles / Q000737:chemistry*; D008863:Microspheres; D058726:Nanoconjugates / Q000737:chemistry*; D011140:Polyurethanes / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared; D014357:Trypsin / Q000737:chemistry* / Q000378:metabolism
chemical_list: D004800:Enzymes, Immobilized; D058726:Nanoconjugates; D011140:Polyurethanes; D006046:Gold; D014357:Trypsin