Poly(2‐ethyloxazoline) as matrix for highly active electrospun enzymes in organic solvents

Abstract

Nanofibers are advantageous carriers for biocatalysts, because they show lower diffusion limitations due to their high surface/volume ratio. Only a few samples are known where enzymes are directly spun into nanofibers, mostly because there are not many suited polymer carriers. In this study, poly(2-ethyloxazoline) (PEtOx) was explored regarding its usefulness to activate various enzymes in organic solvents by directly electrospinning them from aqueous solutions containing the polymer. It was found that the concentration of PEtOx in the spinning solution and also the swellability of the fibers play a great role in the activity of the enzymes in organic solvents. Using electrospun lipase B from Candida antarctica (CaLB) under optimized conditions revealed a higher carrier activity than the commercial Novozyme 435 with 10 times less immobilized protein. The electrospinning of PEtOx/CaLB fibers onto a stirrer is used to realize a biocatalytic stirrer for organic solvents. Biotechnol. Bioeng. 2017;114: 39-45. © 2016 Wiley Periodicals, Inc.

Processing of (Co)Poly(2-oxazoline)s by Electrospinning and Extrusion from Melt and the Postprocessing Properties of the (Co)Polymers

“…The literature data on the formation of non-woven fibrous mats based on POx is limited, and it mainly concerns the electrospinning of commercially available poly(2-ethyl-2-oxazoline) (PEtOx) of high molar mass and broad dispersity (Aquazol®) [38][39][40][41][42][43]. The first study on the optimisation of electrospinning conditions of an aqueous solution of PEtOx (M w of~500,000 g/mol) was described by Buruaga et al [38].…”

“…In turn, George et al [39] obtained ultrafine fibres of cobalt oxide (Co 3 O 4 ) by combining the electrospinning method with high-temperature calcination from the precursor of PEtOx (M w of~500,000 g/mol)/cobalt acetate tetrahydrate in water. High molar mass PEtOx was also used as a potential carrier for the electrospinning of enzymes [40]. Optimisation of the process demonstrated that enzymes were more active after spinning with polymer than spinning alone.…”

Enzyme-induced mineralization of hydrogels with amorphous calcium carbonate for fast synthesis of ultrastiff, strong and tough organic–inorganic double networks

“…Higher temperatures of up to 60°C are possible, but the process becomes diffusion controlled and leads to inhomogeneously mineralized materials. Thus, the 400-500 lm thick films prepared in this work cannot be mineralized faster, but this might not be true for smaller structures, such as enzyme-loaded microparticles [55,56], fibers [57], or thin films [58], which might lead to new materials with interesting mechanical and optical properties. This will be addressed in future studies.…”

Poly(2‐oxazoline)s terminated with 2,2′‐imino diacetic acid form noncovalent polymer–enzyme conjugates that are highly active in organic solvents

“…CT could be activated by a factor of up to 1,000 when solubilized by AOT in organic solvents (Paradkar & Dordick, ), while the activation of this enzyme immobilized on nanoporous silica glass in hexane reached a 110‐fold activity (P. Wang, Dai, Waezsada, Tsao, & Davison, ). CT entrapped in electrospun nanofibers was found to be 400 times more active than the suspended enzyme powder (Plothe et al, ). The best activation of CT found in this study was 250, which is in the order of magnitude of the best‐achieved activations of this enzyme.…”