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Electrochemistry of organometallic lyotropic chromonic liquid crystals (2012)
Journal Article
Halls, J. E., Bourne, R. W., Wright, K. J., Partington, L. I., Tamba, M. G., Zhou, Y., Ramakrishnappa, T., Mehl, G. H., Kelly, S. M., & Wadhawan, J. D. (2012). Electrochemistry of organometallic lyotropic chromonic liquid crystals. Electrochemistry communications, 19(1), 50-54. https://doi.org/10.1016/j.elecom.2012.02.032

Two aqueous lyotropic chromonic liquid crystals made from nickel(II) or copper(II) phthalocyananine tetrasulfonic acid tetrasodium salt are prepared with characterisation through optical polarising microscopy, X-ray diffraction and conductivity. Thes... Read More about Electrochemistry of organometallic lyotropic chromonic liquid crystals.

Concentration-dependent diffusion coefficients of tert-butylferrocene within dodecyltrimethylammonium chloride/brine liquid crystals (2012)
Journal Article
Halls, J. E., Altalhi, A. A., De Abreu, F. C., Goulart, M. O., & Wadhawan, J. D. (2012). Concentration-dependent diffusion coefficients of tert-butylferrocene within dodecyltrimethylammonium chloride/brine liquid crystals. Electrochemistry communications, 17, 41-44. https://doi.org/10.1016/j.elecom.2012.01.013

The title lyotropic liquid crystal is examined as a framework to investigate long-range charge transfer, using tert-butylferrocene (tBuFc) as model hydrophobic system. It is found that the apparent one-dimensional diffusion coefficient depends on the... Read More about Concentration-dependent diffusion coefficients of tert-butylferrocene within dodecyltrimethylammonium chloride/brine liquid crystals.

Voltammetric Immunoassay for the Detection of Protein Biomarkers (2012)
Journal Article
Haswell, S. J., Dou, Y.-H., Wadhawan, J., & Greenman, J. (2012). Voltammetric Immunoassay for the Detection of Protein Biomarkers. Electroanalysis, 24(2), 264-272. https://doi.org/10.1002/elan.201100676

A strategy for a fast (ca. 20 min), specific, electrochemical immunoassay for the cardiac biomarker creatine kinase (CK) and the human cytokine interleukin 10 (IL10) has been developed in this paper. The polyaniline modified gold surface formed from... Read More about Voltammetric Immunoassay for the Detection of Protein Biomarkers.

Electrochemical estimation of diffusion anisotropy of N,N,N′,N′-tetramethyl-para-phenylenediamine within the normal hexagonal lyotropic mesophase of triton X 100/light water: when can the effects of cross-pseudophase electron transfer be neglected for partitioned reagents? (2011)
Journal Article
Halls, J. E., Lawrence, N. S., & Wadhawan, J. D. (2011). Electrochemical estimation of diffusion anisotropy of N,N,N′,N′-tetramethyl-para-phenylenediamine within the normal hexagonal lyotropic mesophase of triton X 100/light water: when can the effects of cross-pseudophase electron transfer be neglected for partitioned reagents?. Journal of Physical Chemistry B, 115(20), 6509-6523. https://doi.org/10.1021/jp201806f

The H1 lyotropic liquid crystalline phase of Triton X 100 with aqueous 0.1 M potassium chloride is examined as a medium in which to determine the axiosymmetric anisotropy in the diffusion flux of N,N,N′,N′-tetramethyl-para-phenylenediamine using elec... Read More about Electrochemical estimation of diffusion anisotropy of N,N,N′,N′-tetramethyl-para-phenylenediamine within the normal hexagonal lyotropic mesophase of triton X 100/light water: when can the effects of cross-pseudophase electron transfer be neglected for partitioned reagents?.

Electron hopping rate measurements in ITO junctions: charge diffusion in a layer-by-layer deposited ruthenium(II)-bis(benzimidazolyl)pyridine-phosphonate- TiO2 film (2011)
Journal Article
Cummings, C. Y., Wadhawan, J. D., Nakabayashi, T., Haga, M. A., Rassaei, L., Dale, S. E., Bending, S., Pumera, M., Parker, S. C., & Marken, F. (2011). Electron hopping rate measurements in ITO junctions: charge diffusion in a layer-by-layer deposited ruthenium(II)-bis(benzimidazolyl)pyridine-phosphonate- TiO2 film. Journal of Electroanalytical Chemistry, 657(1-2), 196-201. https://doi.org/10.1016/j.jelechem.2011.04.010

Focused ion beam (FIB) machining allowed a sub-micron trench to be cut through tin-doped indium oxide (ITO) film on glass to give a generator - collector junction electrode with narrow gap (ca. 600 nm). A layer-by-layer deposited film composed of a d... Read More about Electron hopping rate measurements in ITO junctions: charge diffusion in a layer-by-layer deposited ruthenium(II)-bis(benzimidazolyl)pyridine-phosphonate- TiO2 film.

Biphasic voltammetry of N, N, N ', N '-tetraphenyl-para-phenylenediamine microdroplets, microparticles and microparticle suspensions (2011)
Journal Article
Halls, J. E., & Wadhawan, J. D. (2011). Biphasic voltammetry of N, N, N ', N '-tetraphenyl-para-phenylenediamine microdroplets, microparticles and microparticle suspensions. Electroanalysis, 23(4), 997-1006. https://doi.org/10.1002/elan.201000633

The aqueous biphasic voltammetry of the title compound is examined when it is immobilised on an electrode surface either when dissolved in an array of nitrobenzene droplets, in the form of solid microparticles, or when an electrode is immersed into a... Read More about Biphasic voltammetry of N, N, N ', N '-tetraphenyl-para-phenylenediamine microdroplets, microparticles and microparticle suspensions.

Viability of plant spore exine capsules for microencapsulation (2010)
Journal Article
Barrier, S., Diego-Taboada, A., Thomasson, M. J., Madden, L., Pointon, J. C., Wadhawan, J. D., Beckett, S. T., Atkin, S. L., & Mackenzie, G. (2011). Viability of plant spore exine capsules for microencapsulation. Journal of Materials Chemistry, 21(4), 975-981. https://doi.org/10.1039/c0jm02246b

Sporopollenin exine capsules (SECs) (outer exoskeletal wall of the spores of Lycopodium clavatum) were extracted and examined for their potential use as microcapsules. They were shown, by laser scanning confocal microscopy (LSCM), to be void of their... Read More about Viability of plant spore exine capsules for microencapsulation.

Comparison of Birch with electrochemical reduction of 2,3-diphenyl-1,4- diazaspiro[4.5]deca-1,3-diene (2010)
Journal Article
Zhou, Y., Andreou, A., Biktagirov, E., Eames, J., & Wadhawan, J. (2010). Comparison of Birch with electrochemical reduction of 2,3-diphenyl-1,4- diazaspiro[4.5]deca-1,3-diene. Electrochemistry communications, 12(11), 1493-1497. https://doi.org/10.1016/j.elecom.2010.08.016

Reduction of 2,3-diphenyl-1,4-diazaspiro[4.5]deca-1,3-diene is investigated both voltammetrically (glassy-carbon electrode, 20°C, non-aqueous-solvents) and using dissolving-metals (sodium, −78°C, tetrahydrofuran (THF)/NH3(l)). Remarkably, electro-red... Read More about Comparison of Birch with electrochemical reduction of 2,3-diphenyl-1,4- diazaspiro[4.5]deca-1,3-diene.

Microfluidic perfusion system for maintaining viable heart tissue with real-time electrochemical monitoring of reactive oxygen species (2010)
Journal Article
Cheah, L.-T., Dou, Y. H., Seymour, A. M. L., Dyer, C. E., Haswell, S. J., Wadhawan, J. D., & Greenman, J. (2010). Microfluidic perfusion system for maintaining viable heart tissue with real-time electrochemical monitoring of reactive oxygen species. Lab on a chip, 10(20), 2720-2726. https://doi.org/10.1039/c004910g

A microfluidic device has been developed to maintain viable heart tissue samples in a biomimetic microenvironment. This device allows rat or human heart tissue to be studied under pseudo in vivo conditions. Effluent levels of lactate dehydrogenase an... Read More about Microfluidic perfusion system for maintaining viable heart tissue with real-time electrochemical monitoring of reactive oxygen species.

Amperometric measurement of gaseous hydrogen sulfide via a Clark-type approach (2010)
Journal Article
Horn, J. J., Wadhawan, J., & Mccreedy, T. (2010). Amperometric measurement of gaseous hydrogen sulfide via a Clark-type approach. Analytical Methods, 2(9), 1346-1354. https://doi.org/10.1039/c0ay00338g

The direct oxidation of hydrogen sulfide in the range 2.0-20 parts per million by volume (ppmv) using a Clark-type amperometric gas sensing methodology is investigated via amperometric transients at 298 K. The diluent gas employed is air (20.9% O-2 i... Read More about Amperometric measurement of gaseous hydrogen sulfide via a Clark-type approach.

Electrochemistry and charge transport in sporopollenin particle arrays (2010)
Journal Article
Thomasson, M. J., Baldwin, D. J., Diego-Taboada, A., Atkin, S. L., Mackenzie, G., & Wadhawan, J. D. (2010). Electrochemistry and charge transport in sporopollenin particle arrays. Electrochemistry communications, 12(10), 1428-1431. https://doi.org/10.1016/j.elecom.2010.07.038

Electrochemical oxidation of hollow sporopollenin particles immobilised on an electrode surface is investigated in aqueous acidic solution. Redox activity is demonstrated to occur via a mixture of 2e(-)-2H(+) and 2e(-)-1H(+) processes, likely due to... Read More about Electrochemistry and charge transport in sporopollenin particle arrays.

Immobilized anthraquinone for redox mediation of horseradish peroxidase for hydrogen peroxide sensing (2009)
Journal Article
Dou, Y., Haswell, S., Greenman, J., & Wadhawan, J. (2009). Immobilized anthraquinone for redox mediation of horseradish peroxidase for hydrogen peroxide sensing. Electrochemistry communications, 11(10), 1976-1981. https://doi.org/10.1016/j.elecom.2009.08.032

The detection of hydrogen peroxide is detailed using horseradish peroxidase and anthraquinone. Both species are immobilized on a glassy carbon electrode substrate. This dual immobilization gives rise to lower detection limits compared with the situat... Read More about Immobilized anthraquinone for redox mediation of horseradish peroxidase for hydrogen peroxide sensing.

Electrochemical Determination of Diffusion Anisotropy in Molecularly-Structured Materials (2009)
Journal Article
Evans, L. A., Thomasson, M. J., Kelly, S. M., & Wadhawan, J. (2009). Electrochemical Determination of Diffusion Anisotropy in Molecularly-Structured Materials. Journal of physical chemistry. C, 113(20), 8901-8910. https://doi.org/10.1021/jp806322c

Theory is presented for the case of two-dimensional diffusion anisotropy in axiosymmetric systems, which, advantageously and indirectly, affords a unified theory of diffusive mass transport at planar, microdisk (or nanodisk) and cylindrical electrode... Read More about Electrochemical Determination of Diffusion Anisotropy in Molecularly-Structured Materials.

Electrogenerated chemiluminescence at droplet-modified electrodes: towards biphasic pKₐ measurement via proton-coupled electron transfer at liquid|liquid interfaces (2009)
Journal Article
Lledo-Fernandéz, C., Hatay, I., Ball, M. J., Greenway, G. M., & Wadhawan, J. (2009). Electrogenerated chemiluminescence at droplet-modified electrodes: towards biphasic pKₐ measurement via proton-coupled electron transfer at liquid|liquid interfaces. New journal of chemistry = Nouveau journal de chimie, 33(4), 749-759. https://doi.org/10.1039/b810844g

This preliminary work reports, for the first time, electrogenerated chemiluminescence (ECL) at droplet-modified electrodes. The system involves oxidation of aqueous tris(2,2′-bipyridyl)ruthenium(ii) ions at a glassy carbon electrode on which a random... Read More about Electrogenerated chemiluminescence at droplet-modified electrodes: towards biphasic pKₐ measurement via proton-coupled electron transfer at liquid|liquid interfaces.

pH testing for detecting the position of nasogastric tubes in adults and children (2009)
Journal Article
Kalia, S., Hall, J., El-Habbal, M., Imrie, C., Arabiat, D. H., Shields, L., Allgar, V., Wadhawan, J., Greenman, J., & Elliott, B. (2009). pH testing for detecting the position of nasogastric tubes in adults and children. Cochrane Database of Systematic Reviews, 28126. https://doi.org/10.1002/14651858.cd007660

This is the protocol for a review and there is no abstract. The objectives are as follows: Our objective is to determine if there is sufficient evidence to recommend the use of pH testing (the intervention under scrutiny) for verification of correct... Read More about pH testing for detecting the position of nasogastric tubes in adults and children.

Anion-dependent micelle formation using electro-generated ferrocene surfactants (2008)
Journal Article
Evans, L. A., Apreutesei, D., Mehl, G., & Wadhawan, J. (2008). Anion-dependent micelle formation using electro-generated ferrocene surfactants. Electrochemistry communications, 10(11), 1720-1723. https://doi.org/10.1016/j.elecom.2008.08.046

The syntheses and characterization of two ferrocene oils, 4-octyloxy-2-{5-[1,1,3,3-tetramethyl-3-(11-oxo-11-ferrocenyl-undecyl)-disiloxanyl]-pentyloxy}-benzoic acid 4'-undecyloxy-biphenyl-4-yl ester, Fc1SiM and an octakis(ferrocene) species, Fc8Si8M'... Read More about Anion-dependent micelle formation using electro-generated ferrocene surfactants.

New insights into biological influence on the geochemistry of freshwater carbonate deposits (2008)
Journal Article
Rogerson, M., Pedley, H. M., Wadhawan, J. D., & Middleton, R. (2008). New insights into biological influence on the geochemistry of freshwater carbonate deposits. Geochimica et cosmochimica acta, 72(20), 4976-4987. https://doi.org/10.1016/j.gca.2008.06.030

Ambient temperature freshwater carbonates ("tufas") have outstanding potential as palaeoclimate archives. However, it has proven difficult to constrain the behaviour of the geochemical parameters on which important proxy systems rely. Current thinkin... Read More about New insights into biological influence on the geochemistry of freshwater carbonate deposits.

N-N bond cleavage in N-nitrosoarylamines (2008)
Journal Article
Evans, L. A., Petrovic, M., Antonijevic, M., Wiles, C., Watts, P., & Wadhawan, J. (2008). N-N bond cleavage in N-nitrosoarylamines. Journal of physical chemistry. C, 112(33), 12928-12935. https://doi.org/10.1021/jp710473a

The rupture of N-N bonds in three specific N-nitrosoarylamines (N,N'-dimethyl-N,N-dinitroso-para-phenylenediamine, Cupferron, and N-nitrosodiphenylamine) upon electrochemical oxidation in acetonitrile solution is investigated. In two cases, viz., Cup... Read More about N-N bond cleavage in N-nitrosoarylamines.

Reaction between L-cysteine and 10-methylphenothiazine cation radical released from droplet-modified electrodes (2008)
Journal Article
Horn, J. J., Watson, A., Lewis, M., McCreedy, T., & Wadhawan, J. D. (2008). Reaction between L-cysteine and 10-methylphenothiazine cation radical released from droplet-modified electrodes. Electrochemistry communications, 10(9), 1384-1387. https://doi.org/10.1016/j.elecom.2008.07.021

The electrochemical oxidation of 10-methylphenothiazine (PMe) dissolved in 1,2-trans-dibromocyclohexane oil droplets immobilised on a basal plane pyrolytic graphite (BPPG) electrode and bathed by an aqueous electrolyte is a one-electron quasi-reversi... Read More about Reaction between L-cysteine and 10-methylphenothiazine cation radical released from droplet-modified electrodes.