A simple flow-through reactor system is prepared by covalent linking of a biomolecule on the inner surface of a polyvinyl chloride (PVC) tube. This is achieved by introducing an active functional group oil the surface of an inert PVC tube through 1-fluoro-2-nitro-4-azidobenzene (FNAB), a precursor of highly reactive nitrene, which can insert to any C-H bond. CCl4 lacking C-H bond is taken as a solvent for loading FNAB solution into the tube. FNAB loaded tube is then allowed to expose to sunlight for 20 min during which azido group of FNAB generates nitrene and attaches itself to PVC tube through insertion reaction. Invertase is immobilized in the activated PVC tube at 50 degrees C in 45 min. Invertase embedded-PVC tube is used as a flow-through reactor to convert sucrose to invert Sugar. The flow-through reactor converted Sucrose into invert Sugar with 97% yield as shown by HPLC analysis. The reactor is reused for eight cycles with 17% loss of its initial activity. The reactor system is cheap as PVC tube is working both as a carrier of biomolecule and a reaction vessel. This reactor system overcomes the problem of back pressure and can be used for any enzymatic conversion in a flow-through system. (C) 2008 Elsevier Inc. All rights reserved.