Direct electron transfer from modified glassy carbon electrodes carrying covalently immobilised mediators to a dissolved viologen accepting pyridine nucleotide oxidoreductase and dihydrolipoamide dehydrogenase

Cobalt Polypyridyl Complexes as Redox Mediators for Lipoamide Dehydrogenase

“…Few studies have been published using the second strategy and most of them only present the coupling of the redox mediator with LADH [20][21]. In a few instances, the coupling of LADH with other dehydrogenases (e.g., lactate and alcohol dehydrogenases) has been published [22][23]. The coupling of LADH to other dehydrogenases (e.g., over 200 possibilities) has not been fully exploited despite the fact that FAD/FADH 2 redox couple provides an excellent driving force for NADH electrochemical oxidation.…”

Cages on Surfaces: Thiol Functionalisation of CoIII Sarcophagine Complexes

“…Evidence for the introduction of the carboxymethyl substituent to give the compounds 2 and 3 was observed with peaks between δ ≈ 3.6 and 3.7 ppm in their 1 H NMR and two peaks at δ = 43.6, 52.5 (-CH 2 -) and δ = 172.5, 176.8 (C=O) ppm in their 13 C NMR spectra. The compounds 4, 7 and 8 displayed a single amide -NH-peak (δ = 7.9-8.0 ppm) in their 1 H NMR and a single C=O peak (δ ≈ 170 ppm) in their 13 C NMR spectra due to their CSA moieties.…”

“…Evidence for the introduction of the carboxymethyl substituent to give the compounds 2 and 3 was observed with peaks between δ ≈ 3.6 and 3.7 ppm in their 1 H NMR and two peaks at δ = 43.6, 52.5 (-CH 2 -) and δ = 172.5, 176.8 (C=O) ppm in their 13 C NMR spectra. The compounds 4, 7 and 8 displayed a single amide -NH-peak (δ = 7.9-8.0 ppm) in their 1 H NMR and a single C=O peak (δ ≈ 170 ppm) in their 13 C NMR spectra due to their CSA moieties. The compounds 5, 6, 9 and 10 displayed two peaks in both their 1 H NMR (δ = 7.8-8.2 ppm) and 13 C NMR (δ = 168.7-172.2 ppm) spectra, corresponding to the inequivalent NH and carbonyl centres of the amino acid (Gly or Ala) and CSA.…”

“…[13,20] Logically, it is more appropriate to use an electrophilic centre attached to the cage, because this property should be enhanced by the adjacent charge and indeed it is known that carboxymethyl derivatives of [Co(NH 2 ) 2 -sar] 3+ can be used efficiently in amide and peptide formation reactions. [21] [16] provided reactants to which standard peptide coupling methodologies could be applied to obtain derivatives incorporating cystamine residues as disulfide units linking two cages (Scheme 2).…”

“…[13] Amphiphilic cages [14,15] have also proved to have interesting biological properties, probably associated with their ability to be bound within membranes. [15] As a simple approach to the immobilisation of cage complexes on surfaces, we are currently exploring the use of the wellestablished surface chemistry of disulfides [1] to form monolayers of (sarcophagine)cobalt complexes on gold.…”