Enzyme functionalized solution blown nonwovens

Abstract

ASADUZZAMAN, FNU. Enzyme Functionalized Solution Blown Nonwovens. (Under the direction of Dr. Sonja Salmon). This Ph. D. dissertation presents the innovation and development of a new category of functional materials that uses a solution blown spinning (SBS) process to produce novel, useful biocatalytic functionalized nonwovens. SBS is a rapid, mild nanofiber formation process that is not limited to thermal-plastic polymers or high dielectric constant solvent-soluble polymers. With the SBS technique, it was possible to achieve single-step enzyme immobilization into polymeric carriers from enzyme-compatible polymer solutions. The goals of this research were to explore techniques for preparing polymer-solvent-enzyme compatible triads, optimize solution spinning processes for producing enzyme functionalized solution blown nonwovens (EFSBN), and validate the anticipated application features of EFSBN.Chapter 1 is a review of the literature to assess the potential for compatible polymer-solventenzyme triads for co-immobilization solution processing to increase immobilization yield and reduce immobilization complexity. The particular focus is to produce enzyme compatible polymer solutions in an organic solvent for solution blown spinning process where in-situ fiber formation and enzyme immobilization happen. In-situ co-immobilization is one of the promising methods in enzyme immobilization due to its high enzyme loading, versatility, and single-step fabrication processability. However, the stability and compatibility of enzymes in polymer solutions (especially organic solvent-soluble polymer solutions) are challenging. Enzymes may denature in the presence of organic solvents or at elevated temperatures, limiting how enzymes can be combined with organic solvent-soluble polymers. This chapter discusses strategies for producing compatible polymer-solvent-enzyme triads that span aqueous and non-aqueous fabrication requirements.Chapter 2 reports the novel production of unique enzyme functionalized solution blown nonwoven (EFBSN) webs from aqueous soluble polyethylene oxide (PEO) polymer solution by the solution blow spinning method. Protease co-immobilization via entrapment in PEO nanofibers by solution blowing was demonstrated as a simple and efficient process for loading a broad concentration range of enzymes. The rapidly water-soluble and non-dusting EFSBN solid materials preserve a high enzyme activity level over long periods of ambient storage without adding a stabilizer and are easy to handle, making EFSBNs a potential alternative format for delivering enzymes in products that require fast-dissolving solid formulations, like detergents.Chapter 3 reveals an approach to produce an enzyme (CALB) compatible polycaprolactone (PCL)chloroform solution for enzyme co-immobilization via entrapment in PCL nanofibers. CALB enzymes survived in the microemulsion (water-in-oil) of the PCL-chloroform-CALB compatible triad and retained around half of their initial activity after solution blow spinning. These novel CALB-loaded-EFSBN-PCL ...