Intensification of continuous enzyme-catalyzed furfurylamine synthesis from bio-based furfural using microreactor and deep eutectic solventsBožinović, Marko (Avtor) Damjanović, Anja (Avtor) Seručnik, Mojca (Avtor) Cvjetko Bubalo, Marina (Avtor) Žnidaršič Plazl, Polona (Avtor) furfurylaminebiomass valorizationdeep eutectic solventsgreen chemistrymicroreactorflow chemistryFurfurylamine (FA) is an important biomass-derived intermediate with broad applications across many industries. Although biocatalytic routes provide a sustainable alternative to conventional synthesis, their industrial implementation is often limited by low substrate loadings and excessive amine donor requirements. In this study, an intensified continuous-flow biocatalytic process for FA synthesis from furfural (FUR) was developed through the integrating of enzyme N-His6-ATA-wt immobilization on magnetite nanoparticles, reaction medium engineering using deep eutectic solvents (DESs), and microreactor technology. A series of aqueous DESs solutions was systematically screened to improve substrate solubility while preserving enzymatic activity, leading to 49.17 wt% betaine–propylene glycol (1:3) DES in potassium phosphate buffer (pH 6.5, 100 mM), Bet:PG49.17, as the optimal reaction medium. The solubility of the less soluble substrate, (S)-(−)-α-methylbenzylamine (MBA), increased 8.33-fold in Bet:PG49.17 compared to the buffer, while enzymatic activity was fully retained relative to the buffer system (98.98%). Enzyme shelf-life studies demonstrated that the immobilized enzyme exhibited significantly enhanced long-term stability in the DES-containing medium at 25 °C, with a 4.55-fold increase in half-life compared to the immobilized enzyme in buffer. FUR bioamination conducted with an equimolar ratio of the amine donor at a concentration of 100 mM, using enzyme immobilized in a magnetic field-assisted microreactor, achieved a gross yield 87.50% and a space–time yield of 6.43 g/(L h). Moreover, permeation of volatile components through the reactor material enabled in situ removal of inhibitory coproducts, acetophenone, preventing its accumulation and affecting the preserving enzyme activity and in situ removal of the unreacted substrates.20262026-05-07 12:41:02Neznano182334sl