Ferrocenes/ferrocenyls ferrocene methanol

This immunosensor-type assay uses ferrocene methanol as co-substrate (redox mediator) of glucose oxidase (GOD). The various steps of the assay, shown in Fig. 8.20, are as follows (1) Covalent immobilization of protein A on graphite-polystyrene screen-printed electrodes (SPEs) (2) Addition of the rabbit IgG to be quantified which is captured specifically by protein A (3) Addition of a biotinylated goat anti-rabbit antibody (4) Addition of avidin-GOD conjugate (5) Addition of glucose and ferrocene methanol (6) Measurement of catalytic current by flow injection immunoassay. The voltammetric current corresponds to the one-electron oxidation of the ferrocenyl group to ferricinium. The electrode can subsequently be regenerated up to 30 times. The feasibility of the assay has been demonstrated for the case of monoclonal mouse anti-human prolactin (PL) with a detection limit of 0.02 pg mL [90]. 

The synthesis of the unsymmetrical imidazolium salt 11 bearing a planar-chiral ferrocene was described by Bolm starting from (Rp)-[2-(trimethysilyl)-ferrocenyl] methanol 12 which afforded the salt in good yield after reaction with Ar,M-carbonyl diimidazole and methylation (Scheme 9) [18]. 

TLC has been carried out on silica gel G layers, using the solvents I benzene II benzene-ethanol (90 + 3) III benzene-ethanol (90 + 6) IV propane-1,2-diol-methanol (50 + 50) and V chlorobenzene-propane-1,2-diol-methanol (33 + 33 + 33). In this way, ferrocenyl-methanol, ferrocene ketones, esters, ethers and nitrogen-containing derivatives can be separated, whereas ferrocene and ferrocenyl-hydro-carbons migrate with the front n-hexane is suitable for separating these last named. 

The addition of dithiols to diolefins is a well-established method for the synthesis of polymers [26-28]. Reaction of l,T-dimercapto-ferrocene with norbomadiene in toluene in the presence of AIBN as initiator and heating to 70 °C yielded a yellow powder after precipitation in methanol. The GPC shows a homologous series of oligomers in which the first members were identified by FD-MS with mte = 682, 930, 1179. Instead of the expected alternating copolymers from ferrocene and norbomene, bridged by sulphur, only oligomers of ferrocenyl disulphides with norbomene or nortricyclyl end groups were detected (Scheme 15.7). 

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