Developing enzyme immobilization with aluminium-coated and gold-coated membranes

Sample pretreatment methods such as membrane filtration and enzymatic digestion show high separation efficiency and biogenic matter purification efficiency for microplastic particles, although the whole sample preparation process is time- and money-consuming. In this work, enzymes, e.g. cellulase and laccase, were immobilized on the aluminium-coated and gold-coated polyester membranes, aiming for the simultaneous digestion and separation of organic matter from microplastic particles for their further qualitative and quantitative analyses. The immobilization process has been successfully performed for both analyzed enzymes and matrices. Membrane morphology analysis confirmed significant changes in the surface topography and parameters upon enzyme immobilization. However, only laccase immobilized on aluminium-coated membranes showed satisfactory results, having regard to retained enzyme activity. This research is expected to open the doors for the preparation and utilization of membranes containing immobilized enzymes in the efficient and fast pretreatment of microplastic particles from water samples. • Enzyme immobilization on gold- and aluminium-coated membranes was performed • Successful protein deposition on the membranes was verified with various techniques • High immobilization efficiency was paired with high activity only for Laccase/Al-PE • Water flux for the membranes decreased from 21% to 50% upon immobilization