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Abrantes, L. M., C. M. Cordas, and E. Vieil. "EQCM study of polypyrrole modified electrodes doped with Keggin-type heteropolyanion for cation detection." Electrochimica Acta. 47.9 (2002): 1481-1487. AbstractWebsite

The incorporation of a Keggin-type heteropolyanion, the phosphotungstate ([PW12O40](3-)), into polypyrrole has been achieved during the electrochemical preparation of the polymer films in aqueous solution. The redox behaviour of these modified electrodes is described by using cyclic voltammetry (CV) and electrochemical quartz crystal microbalance (EQCM). The data allowed to estimate the doping level that indicates the extent of the heteropolyanion insertion. It is found that the polymer films, in aqueous solution, exhibit sensibility to cations, namely to Na+. (C) 2002 Elsevier Science Ltd. All rights reserved.

Cordas, C. M., A. Tenreiro, and L. M. Abrantes EQCM study on the polytyramine modified electrodes for the preparation of biosensors. Eds. Y. G. Gogotsi, and I. V. Uvarova. Vol. 102. Nanostructured Materials and Coatings for Biomedical and Sensor Applications, 102., 2003. AbstractWebsite
Cordas, C. M., A. S. Viana, S. Leupold, F. P. Montforts, and L. M. Abrantes. "Self-assembled monolayer of an iron(III) porphyrin disulphide derivative on gold." Electrochemistry Communications. 5.1 (2003): 36-41. AbstractWebsite

A novel iron(III) porphyrin disulphide derivative have been successfully immobilised on gold surfaces by self-assembly. The redox response of the modified electrodes was compared with the obtained for a similar iron porphyrin in solution, confirming the immobilisation of the metalloporphyrin. The gravimetric data obtained by electrochemical quartz crystal microbalance (EQCM) during adsorption allowed an estimation of the electrode coverage, providing further evidence for the formation of the porphyrin SAM. The modified electrodes were also measured by conventional and imaging ellipsometry. The electrocatalytic activity of the two modified electrodes was tested for the reduction of the molecular oxygen. (C) 2002 Elsevier Science B.V. All rights reserved.

Auchere, F., R. Sikkink, C. Cordas, P. Raleiras, P. Tavares, I. Moura, and JJG Moura. "Overexpression and purification of Treponema pallidum rubredoxin; kinetic evidence for a superoxide-mediated electron transfer with the superoxide reductase neelaredoxin." Journal of Biological Inorganic Chemistry. 9.7 (2004): 839-849. Abstract
Cordas, C. M., AS Pereira, C. E. Martins, C. G. Timoteo, I. Moura, JJG Moura, and P. Tavares. "Nitric oxide reductase: Direct electrochemistry and electrocatalytic activity." Chembiochem. 7.12 (2006): 1878-1881. AbstractWebsite
Cordas, C. M., L. T. Guerra, C. Xavier, and JJG Moura. "Electroactive biofilms of sulphate reducing bacteria." Electrochimica Acta. 54.1 (2008): 29-34. AbstractWebsite

Biofilms formed from a pure strain of Desulfovibrio desulfuricans 27774 on stainless steel and graphite polarised surfaces were studied. The polarisation conditions applied were -0.4V vs. SCE for different times. A cathodic current related with the biofilms growth was observed with a maximum intensity of -270 mA m(-2) that remained stable for several days using graphite electrodes. These sulphate reducing bacteria biofilms present electrocatalytic activity towards hydrogen and oxygen reduction reactions. Electrode polarisation has a selective effect on the catalytic activity. The biofilms were also observed by scanning electronic microscopy revealing the formation of homogeneous films on the surfaces. (c) 2008 Elsevier Ltd. All rights reserved.

Cordas, C. M., I. Moura, and JJG Moura. "Direct electrochemical study of the multiple redox centers of hydrogenase from Desulfovibrio gigas." Bioelectrochemistry. 74.1 (2008): 83-89. AbstractWebsite

Direct electrochemical response was first time observed for the redox centers of Desulfovibrio gigas [NiFe]-Hase, in non-turnover conditions, by cyclic voltammetry, in solution at glassy carbon electrode. The activation of the enzyme was achieved by reduction with H(2) and by electrochemical control and electrocatalytic activity was observed. The inactivation of the [NiFe]-Hase was also attained through potential control. All electrochemical data was obtained in the absence of enzyme inhibitors. The results are discussed in the context of the proposed mechanism currently accepted for activation/inactivation of [NiFe]-Hases. (C) 2008 Elsevier B.V. All rights reserved.

Cordas, C. M., N. M. T. Lourenco, P. Vidinha, CAM Afonso, S. Barreiros, L. P. Fonseca, and J. M. S. Cabral. "New conducting biomaterial based on Ion Jelly (R) technology for development of a new generation of biosensors." New Biotechnology. 25 (2009): S138-S139. AbstractWebsite
Cordas, C. M., J. Wilton, T. Cardoso, F. Folgosa, AS Pereira, and P. Tavares. "Electrochemical behaviour of Dps-a mini-ferritin." European Biophysics Journal with Biophysics Letters. 40 (2011): 181. AbstractWebsite
Folgosa, F., C. M. Cordas, J. A. Santos, AS Pereira, JJG Moura, P. Tavares, and I. Moura. "New spectroscopic and electrochemical insights on a class I superoxide reductase: evidence for an intramolecular electron-transfer pathway." Biochemical Journal. 438 (2011): 485-494. AbstractWebsite

SORs (superoxide reductases) are enzymes involved in bacterial resistance to reactive oxygen species, catalysing the reduction of superoxide anions to hydrogen peroxide. So far three structural classes have been identified. Class I enzymes have two ironcentre-containing domains. Most studies have focused on the catalytic iron site (centre II), yet the role of centre I is poorly understood. The possible roles of this iron site were approached by an integrated study using both classical and fast kinetic measurements, as well as direct electrochemistry. A new heterometallic form of the protein with a zinc-substituted centre I, maintaining the iron active-site centre II, was obtained, resulting in a stable derivative useful for comparison with the native all-iron from. Second-order rate constants for the electron transfer between reduced rubredoxin and the different SOR forms were determined to be 2.8 x 10(7) M(-1) . s(-1) and 1.3 x 10(6) M(-1) . s(-1) for SOR(Fe(IIII)-Fe(II)) and for SOR(Fe(IIII)-Fe(III)) forms respectively, and 3.2 x 10(6) M(-1) s(-1) for the SOR(Zn(II)-Fe(III)) form. The results obtained seem to indicate that centre I transfers electrons from the putative physiological donor rubredoxin to the catalytic active iron site (intramolecular process). In addition, electrochemical results show that conformational changes are associated with the redox state of centre I, which may enable a faster catalytic response towards superoxide anion. The apparent rate constants calculated for the SOR-mediated electron transfer also support this observation.

Cordas, C. M., P. Raleiras, F. Auchere, I. Moura, and JJG Moura. "Comparative electrochemical study of superoxide reductases." European Biophysics Journal with Biophysics Letters. 41.2 (2012): 209-215. AbstractWebsite

Superoxide reductases are involved in relevant biological electron transfer reactions related to protection against oxidative stress caused by reactive oxygen species. The electrochemical features of metalloproteins belonging to the three different classes of enzymes were studied by potentio-dynamic techniques (cyclic and square wave voltammetry): desulfoferrodoxin from Desulfovibrio vulgaris Hildenborough, class I superoxide reductases and neelaredoxin from Desulfovibrio gigas and Treponema pallidum, namely class II and III superoxide reductases, respectively. In addition, a small protein, designated desulforedoxin from D. gigas, which has high homology with the N-terminal domain of class I superoxide reductases, was also investigated. A comparison of the redox potentials and redox behavior of all the proteins is presented, and the results show that SOR center II is thermodynamically more stable than similar centers in different proteins, which may be related to an intramolecular electron transfer function.

Calado, L. M., C. M. Cordas, and J. P. Sousa. "Acemetacin and indomethacin detection using modified carbon microelectrodes." Analytical and Bioanalytical Electrochemistry. 5.6 (2013): 665-671. AbstractWebsite
Cordas, C. M., A. G. Duarte, JJG Moura, and I. Moura. "Electrochemical behaviour of bacterial nitric oxide reductase - Evidence of low redox potential non-heme FeB gives new perspectives on the catalytic mechanism." Biochimica et Biophysica Acta - Bioenergetics. 1827.3 (2013): 233-238. AbstractWebsite
Cordas, Cristina M., Americo G. Duarte, Jose J. G. Moura, and Isabel Moura. "Electrochemical behaviour of bacterial nitric oxide reductase-Evidence of low redox potential non-heme Fe-B gives new perspectives on the catalytic mechanism." Biochimica Et Biophysica Acta-Bioenergetics. 1827.3 (2013): 233-238. Abstract
Dall'Agnol, L. T., C. M. Cordas, and JJG Moura. "Influence of respiratory substrate in carbon steel corrosion by a Sulphate Reducing Prokaryote model organism." Bioelectrochemistry. 97 (2014): 43-51. AbstractWebsite
Duarte, A. G., C. M. Cordas, JJG Moura, and I. Moura. "Steady-state kinetics with nitric oxide reductase (NOR): New considerations on substrate inhibition profile and catalytic mechanism." Biochimica et Biophysica Acta - Bioenergetics. 1837.3 (2014): 375-384. AbstractWebsite
Santos, T. C., A. R. De Oliveira, J. M. Dantas, C. A. Salgueiro, and C. M. Cordas. "Thermodynamic and kinetic characterization of PccH, a key protein in microbial electrosynthesis processes in Geobacter sulfurreducens." Biochimica et Biophysica Acta - Bioenergetics. 1847.10 (2015): 1113-1118. AbstractWebsite
Carvalho, R. N. L., R. M. Almeida, JJG Moura, N. T. Lourenço, L. J. P. Fonseca, and C. M. Cordas. "Sandwich-Type Enzymatic Fuel Cell Based on a New Electro-Conductive Material - Ion Jelly." ChemistrySelect. 1.20 (2016): 6546-6552. AbstractWebsite
Matias, S. C., N. M. T. Lourenço, L. J. P. Fonseca, and C. M. Cordas. "Comparative Electrochemical Behavior of Cytochrome c on Aqueous Solutions Containing Choline-Based Room Temperature Ionic Liquids." ChemistrySelect. 2.27 (2017): 8701-8705. AbstractWebsite
Ramos, S., R. M. Almeida, C. M. Cordas, JJG Moura, S. R. Pauleta, and I. Moura. "Insights into the recognition and electron transfer steps in nitric oxide reductase from Marinobacter hydrocarbonoclasticus." Journal of Inorganic Biochemistry. 177 (2017): 402-411. AbstractWebsite
Samhan-Arias, A. K., S. Fortalezas, C. M. Cordas, I. Moura, JJG Moura, and C. Gutierrez-Merino. "Cytochrome b5 reductase is the component from neuronal synaptic plasma membrane vesicles that generates superoxide anion upon stimulation by cytochrome c." Redox Biology. 15 (2018): 109-114. AbstractWebsite
Rebocho, S., C. M. Cordas, R. Viveiros, and T. Casimiro. "Development of a ferrocenyl-based MIP in supercritical carbon dioxide: Towards an electrochemical sensor for bisphenol A." Journal of Supercritical Fluids. 135 (2018): 98-104. AbstractWebsite
Rosa, V., A. P. S. Gaspari, F. Folgosa, C. M. Cordas, P. Tavares, T. Santos-Silva, S. Barroso, and T. Avilés. "Imine ligands based on ferrocene: Synthesis, structural and Mössbauer characterization and evaluation as chromogenic and electrochemical sensors for Hg2+." New Journal of Chemistry. 42.5 (2018): 3334-3343. AbstractWebsite
Gomes, F. O., L. B. Maia, C. Cordas, C. Delerue-Matos, I. Moura, JJG Moura, and S. Morais. "Nitric Oxide Detection Using Electrochemical Third-generation Biosensors – Based on Heme Proteins and Porphyrins." Electroanalysis. 30.11 (2018): 2485-2503. AbstractWebsite
Samhan-Arias, A. K., L. B. Maia, C. M. Cordas, I. Moura, C. Gutierrez-Merino, and JJG Moura. "Peroxidase-like activity of cytochrome b5 is triggered upon hemichrome formation in alkaline pH." Biochimica et Biophysica Acta - Proteins and Proteomics. 1866.2 (2018): 373-378. AbstractWebsite