Enzyme immobilisation: Typically, 10 mg NH2-coated ProntoSIL was suspended in ethanol (1 ml) followed by addition of the HaloTag TM -targeting chloroalkane linker (S1, for structure, see ESI Fig. (104 µl, 100 mM stock solution in ethanol) and trimethylamine (5.0 µl). After incubation at rt for 16 h at 1200 rpm shaking, the particles were centrifuged and washed with ethanol (3 × 1 ml). Linker loading was determined afterward by Kaiser Test (for detailed information, see ESI section S4.2). For reactor runs using particles without a linker the same strategy was used. However, only ethanol was added instead of the HaloTag TM -targeting chloroalkane linker S1 solution. Finally, CiVHPOHalo (15.9 µl, 3.142 µg/µl stock solution) and buffer (484 µl, containing 50 mM Tris pH 6.0 and 100 µM Na3VO4) were added to the particles, and the mixture was incubated at rt for 1 h at 1000 rpm shaking. The particles were washed with MES buffer (3 × 1 ml). Interestingly, after immobilisation, a good retention of 68% of the initial activity for CiVHPOHalo on ProntoSIL was observed (for detailed information, see ESI Fig. ).