title: Stable encapsulation of active enzyme by application of multilayer nanofilm coatings to alginate microspheres.
abstract: In an effort to improve the stability for long-term biosensor use, layer-by-layer self-assembly was explored as a potential technique to provide a diffusion barrier to encapsulated glucose oxidase inside alginate microspheres (<5 microm), fabricated using an emulsification technique. The total loss of encapsulated enzyme was reduced to less than 25 and 15% with the application of single PAH/PSS and crosslinked PAH/PAA coatings, respectively, in comparison to at least a 45% loss observed with uncoated and PDDA/PSS-coated microspheres. Furthermore, it was found that enzyme within PAH/PSS- and crosslinked PAH/PAA-coated spheres retained more than 84 and 60% of initial activity, respectively, after three months, whereas uncoated and PDDA/PSS-coated microspheres retained less than 20%.
authors.affiliation: Biomedical Engineering and Institute for Micromanufacturing, Louisiana Tech University, Ruston, LA 71272, USA.
authors.forename: Rohit
authors.initials: R
authors.lastname: Srivastava
authors.forename: Jonathan Q
authors.initials: JQ
authors.lastname: Brown
authors.forename: Huiguang
authors.initials: H
authors.lastname: Zhu
authors.forename: Michael J
authors.initials: MJ
authors.lastname: McShane
mesh_terms: D000464:Alginates / Q000737:chemistry*; D001234:Aspergillus niger / Q000201:enzymology*; D015374:Biosensing Techniques / Q000379:methods; D004800:Enzymes, Immobilized / Q000737:chemistry; D005656:Fungal Proteins / Q000737:chemistry*; D005949:Glucose Oxidase / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D008863:Microspheres; D036103:Nanotechnology / Q000379:methods
chemical_list: D000464:Alginates; D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D005949:Glucose Oxidase