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Intact photosensitive cyclometalated [Ru.sup.II] derivatives of 2-phenylpyridine or N,N-dimethylbenzylamine cis-[Ru-(C~N) (LL)[X.sub.2]] [PF.sub.6][C~N : o-[C.sub.6][H.sub.4]-py or o-[C.sub.6][H.sub.4]C[H.sub.2]N[Me.sub.2]; LL = 1,10-phenanththroline (phen), 2,2'-bipyridine (bpy), or 4,4'-[Me.sub.2]-2,2'-bipyridine ([Me.sub.2]bpy); X = MeCN or pyridine (py)] are efficient mediators of glucose oxidase (GO) from Aspergillus niger and horseradish peroxidase (HRP). Their redox potentials in an aqueous buffer are in the range 0.15-0.35 V versus SCE, and the rate constants for the oxidation GO(red) (where red indicates reduced) by the electrochemically generated [Ru.sup.III] species equal (1.7-2.5) x [10.sup.6] [M.sup.-1] [s.sup.-1] at pH 7 and 25[degrees]C. The redox potentials of all complexes decrease cathodically by 0.4-0.6 V upon irradiation by visible light because of the photoinduced solvolysis of acetonitrile or py ligands. These in situ generated species display an even better mediating performance with HRP, although their behavior toward GO is different. The loading of a ruthenium unit into the protein interior brings about large catalytic currents in a self-assembled system GO--Ru--D-glucose. The estimated rate constant for intramolecular electron transfer from FAD[H.sub.2] of the active site at [Ru.sup.III], [k.sub.intra], equals 4.4 x [10.sup.3] [s.sup.-1]]. This suggests that the distance between the redox partners is around 19 [Angstrom]. The value of 21 [Angstrom] was obtained through the docking analysis of a possible closest-to-FAD localization of a Ru-containing fragment derived from the irradiated complex cis-[Ru(o-[C.sub.6][H.sub.4]-py)-(phen) [(MeCN).sub.2]][PF.sub.6]. The operational stability of the GO-Ru assemblies depends on the nature of complex used, the highest being observed for cis-[Ru(o-[C.sub.6][H.sub.4]-py)([Me.sub.2]bpy)[(MeCN).sub.2]][PF.sub.6] (2). UV--vis studies of interaction of 2 with GO revealed photomechanical oscillations in the system GO--Ru--D-glucose. When irradiated complex 2 is mixed with GO and D-glucose, the absorbance at 510 nm increases because of the enzymatic reduction of [Ru.sup.III] to [Ru.sup.II]. The absorbance drops rapidly and then increases as in the first cycle after shaking the reaction solution. Many cycles are possible, and the rate of absorbance increase does not depend on a cycle number. A plausible mechanism of the oscillations is presented.

The reaction of amylose with NaH and FcC[H.sub.2]N[[Me.sub.3].sup.+][I.sup.-] in dimethyl sulfoxide brought about a redox-labeled polymer with a low degree of modification, viz. 1 ferrocene residue per 60 glucose units. The preparation, (0.017ferrocene)amylose, displays one-electron irreversible behavior at a pyrographite electrode in terms of the Delahay formalism, the formal redox potential E [degree] [prime] being equal to 0.38 V at pH 6 and 40 [degrees] C versus SCE. Specific to amylose enzymes endo-depolymerases, which carry out random hydrolysis, accept the labeled amylose providing a significant increase in the peak current on cyclic voltammograms. The absence of potential drifts suggests that the effect is due an increase in the diffusion coefficients of the amylose fragments in the course of enzymatic digestion of (0.017ferrocene)amylose. This proposal was confirmed by the simulation of experimental cyclic voltammograms. Several practical applications of the results of this study for electro-chemical assaying the amylolytic activity and evaluation of the mechanisms of the enzymatic catalysis by amylases have been demonstrated.