Universal enzyme immobilisation within hierarchically-assembled magnetic scaffolds
Immobilisation is often a necessary step in making industry-ready enzymes from a process-stability and cost-effectiveness standpoint but is often hit or miss.. We describe a universal method using hierarchical magnetic materials to optimize the activity, stability and loadings of any enzymes. The immobilisation of 7 enzymes from different classes was demonstrated with mass-loadings up to 28% by mass. The enzymes were magnetically stabilised and assembled onto high-magnetic susceptibility scaffolds (6.14×10-4 m3/kg). Upon immobilisation, the efficiencies (kcat/Km) of the enzymes were fully retained andeven enhanced in the case of glucose oxidase, glucose isomerase and catalase. The inhibition of horseradish peroxidase was lowered by 22-fold once immobilised. Magnetic-driven processing, i.e. the use of external electromagnets to process and control the magnetic carriers during batch reactions, was successfully demonstrated; the immobilised enzymes performed as well as the free enzymes or even surpassed them in the case of the peroxidase.
With the progresses in bioengineering and bioprocessing over the last decades, enzymes have successfully been used for the biocatalytic production of active pharmaceutical ingredients (APIs) and chemicals. The most important aspect of biocatalysis for drug manufacturing is the high selectivity of the reaction performed by enzymes as a result of stereoselectivity (producing only one chiral form of an isomer), regioselectivity (acting on specific site of the substrate), and chemoselectivity (acting exclusively on one functional group of the substrate) (1).
Additionally, enzymes have high reaction rates under mild temperatures, pressures and pHs, which allow for easily implemented and scalable processes. Due to high yields and high purity, biocatalysis obviates many synthetic steps, eliminates complex post-synthesis purification steps, and improves the efficiency in the use of the raw ingredients (Efactor) (2). Consequently, biocatalysis reduces waste and environmental impacts of chemical manufacturing (3).
To make biocatalysts more ubiquitous in the tool box of chemical engineers, wild-type or bioengi ...