Hydrogel composites with temperature induced phase transition for biocatalysis

Abstract

BACKGROUND: This paper focuses on the development of temperature induced phase transition hydrogels based on poly(Nisopropylocrylamide (PNIPA) copolymers and their application as an immobilization matrix for biocatalysts.

Immobilization of Water-Soluble HRP within Poly-N-isopropylacrylamide Microgel Particles for Use in Organic Media

“…In other studies, lysozyme and trypsin were immobilized within p-NIPAM microgel particles with a diameter of between 50 and 80 μm where the location of the enzymes within the polymer structure was detectable by confocal laser scanning microscopy (CLSM). − Although enhanced activity is reached, the described studies investigated the activity exclusively in water. Another study presents the immobilization of lipase within p-NIPAM macrogels, leading to enhanced activity in organic solvents . To benefit from the low polydispersity and the high surface-to-volume ratio, it is more efficient to use smaller p-NIPAM particles.…”

“…Another study presents the immobilization of lipase within p-NIPAM macrogels, leading to enhanced activity in organic solvents. 28 To benefit from the low polydispersity and the high surface-to-volume ratio, it is more efficient to use smaller p-NIPAM particles. In previous studies, the enzyme lipase B from Candida antarctica (CalB) was immobilized within p-NIPAM microgel particles by exchanging water for an organic solvent.…”

Immobilization of lipase B within micron-sized poly-N-isopropylacrylamide hydrogel particles by solvent exchange

“…The immoblized amount of enzyme at different temperatures, the enzyme distribution within the polymer particles, the activity at different reaction temperatures and the reusability of the system applying CLSM and gas chromatography were investigated. In the literature, the usage of immobilized systems in organic solvents was either shown for macrogels with no enhanced specific activity [26][27][28] or for reversed micelles where the location of the enzyme was not invetsigated. 29 In the present paper the location of the enzyme CalB was determined and an enhanced activity in organic solvents is reached.…”

Responsive microgels and microgel assemblies in biocatalytic applications

“…However, a reversible binding alternative can facilitate enzyme loading and unloading during the swelling and deswelling of the polymer with LCST, and the reverse applies for UCST polymer. 82 This makes it easier to separate products from enzymes. One such method employs thermoresponsive moietyfunctionalized microgel to facilitate mass diffusion of substrate and product across the immobilized enzyme inside the gel particle by ramping up the temperature.…”