Highly active engineered-enzyme oriented monolayers: formation, characterization and sensing applications.

Background: The interest in introducing ecologically-clean, and efficient enzymes into modern industry has been growing steadily. However, difficulties associated with controlling their orientation, and maintaining their selectivity and reactivity is still a significant obstacle. We have developed precise immobilization of biomolecules, while retaining their native functionality, and report a new, fast, easy, and reliable procedure of protein immobilization, with the use of Adenylate kinase as a model system.

Reactions of the transient species Cr(CO)5(cyclohexane) with C4HnE (n=4, 8; E=O, NH, S) studied by time-resolved IR absorption spectroscopy.

Time-resolved IR absorption spectroscopy is used to investigate substitution of the cyclohexane (CyH) molecule of the photolytically generated alkane-solvated transient intermediate Cr(CO)5(CyH) by heterocyclic ligands C4HnE (n=4, 8; E=O, NH, S). From the concentration and temperature dependences of the pseudo-first order rate constants, we obtain activation parameters for the reactions, and find that they are consistent with an associative (A) or interchange (I) mechanism. As was the case with ligand substitution reactions at W(CO)5(CyH), a ligand's reactivity depends both on its electron-donating ability and on its polarizability.