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AN INTERNATIONAL WORKSHOP, JUNE 25 TH TO 26 TH 2015 CEST/WIENER NEUSTADT BIOELECTROCHEMISTRY AND MORE
AN INTERNATIONAL WORKSHOP, JUNE 25TH TO 26TH 2015CEST/WIENER NEUSTADT
BIOELECTROCHEMISTRY AND MORE
The AIT Austrian Institute of Technology and CESTinvite you to the lecture series:
Thursday, 25th June 2015 - Friday, 26th June 2015Lecture Hall TFZ, 1st floor, Unit ACEST Centre of Electrochemical Surface TechnologyViktor-Kaplan-Straße 2, 2700 Wiener Neustadt phone: +43-2622-22266-10 fax.: +43-2622-22266-50mail: [email protected] I www.cest.at
DateLocation
» BIOELECTROCHEMISTRY AND MORE ...«
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Thursday, June 25th
All Morning: arrival of workshop speakersMounting of Posters PhD Student Seminar with Poster SessionSandwichesWelcomeChristoph Kleber (CEST)Wolfgang Knoll (AIT Austrian Institute of Technology GmbH)Carbon Nanotube Chemiresistors: Inexpensive, Low Power, Sensitive Chemical SensorsTimothy SwagerCarbon Nanotube Sensing Schemes and DevicesAlagappan PalaniappanDieelectric and Semiconductor Surface Interfacial Interactions for Chemical and Biochemical Sensing using Organic ElectronicsHoward KatzMultimodal Sensing by Organic Field Effect Device:Chemical, Physical, Biosensing with the same sensing platformAnnalisa BonfiglioCoffee and PostersResponsive Polymer Architectures - from Hydrogels to Sensors Ulrich JonasSmart, Redox Responsive Organometallic Polymer Platforms in Sensing and Release and as nanoparticle foundryG. Julius VancsoBiosensors and biofuel cells based of redox hydrogelsWolfgang SchuhmannStimuli Responsive Thin FilmsA. Toby A. JenkinsEnd of Lecture Day 1
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Friday, June 26th
Lecture Hall TFZ, 1st floor, Unit AAnalysis of Macromolecules at Electrolyte/Solid interfaces Guido GrundmeierProtein Electrochemical OxidationAna Maria Oliviera-BrettElectrochemical Delivery Platform of Insulin on DemandSabine SzuneritsCoffeeSkin Inspired Electronics Based on Organic MaterialsZhenan BaoHighly Sensitive Electrochemical and Electrochemilumi-niscent Detection of Celiac Disease Biomarkers at Gold Nanoelectrode EnsemblesPaolo UgoClosing RemarksLunch and PostersLab Tour (optional)
Carbon nanotube networks represent a powerful platform for the gene-ration of chemiresistive sensors. Through the selective chemical func-tionalization with selector molecules and/or receptors, the conductance can be made selective to the presence of analytes ranging from large biological macromolecules to small gaseous molecules. This lecture will detail the fabrication of robust sensors using new functionalization chemistry to impart selectivity to the carbon nanotubes and methods to minimize drift. Sensor arrays with low levels of cross-reactivity bet-ween sensor elements will be discussed for the robust classification of chemicals. The use of carbon nanotube-based gas sensors for the de-tection of ethylene and other gases relevant to the monitoring fruit and produce ripeness will be presented. Gas sensors for agricultural and food production/storage/transportation are being specifically targeted and can be used to create systems that increase production, manage inventories, and minimize losses.
CARBON NANOTUBE CHEMIRESISTORS: INEXPENSIVE, LOW POWER, SENSITIVE CHEMICAL SENSORS
Timothy M. Swager
Massachusetts Institute of
TechnologyDepartment of
Chemistry77, Massachusetts
AvenueCambridge,
MA 02139Email:
CARBON NANOTUBE SENSING SCHEMES AND DEVICES
Carbon nanotubes (CNTs) have emerged to be an exciting class of ma-terials for gas and biosensing applications owing to their unique elec-trical and physical properties. This talk focuses on assay formats deve-loped at CBSS using both commercially available and chemical vapor deposition (CVD) synthesized CNT. CNT controllable morphology and their high surface to volume ratio have been utilized for fabrication of sensitive field effect transistors and micro-gravimetric sensors. Selec-tive detection of analytes such as small molecules, biomarkers, volatile organic compounds, etc., was achieved via appropriate functionalizati-on of CNT with recognition molecules. Sub-nM detection sensitivities have been obtained using the adopted approaches, indicating that the fabricated devices respond to analytically relevant concentration regi-mes.
Alagappan Palaniappan
Center for Biomimetic
Sensor ScienceNanyang Techno-logical University
50 Nanyang Drive, Singapore 637553
E-mail: [email protected]
Surface dipole and charge density modulations resulting from chemical binding to electronic material interfaces lead to electronic responses in field effect and chemoresistive devices. This talk will discuss two diffe-rent pathways toward maximum chemical sensitivity for small molecule (vapor) sensing and for biomacromolecule (protein) sensing. The first pathway is to increase the semiconductor surface accessibility, its ana-lyte binding capability, and the match in charge carrier energy level with vapor analyte molecular orbitals to increase the transduction of molecu-lar adsorption to a conductivity change. We use such strategies to achieve ten-ppb detection of ammonia for the purpose of correlating its environmental concentration with adverse health effects. The second pathway is to modify the compositions of top dielectric capacitive coup-ling layers, comprising hydrocarbon and fluorinated polymers and at-tachment groups, so that the change in ion distribution resulting from the presence of bound proteins exerts the maximum field effect on an organic semiconductor lying under the coupling layer. We detect ng/mL levels of the brain injury biomarker GFAP with this strategy, the highest protein sensitivity reported for an organic transistor, as well as opposite polarity responses in the two legs of a complementary (n and p semicon-ductor) inverter circuit.Use of printable materials in these technologies will be emphasized.
DIELECTRIC AND SEMICONDUCTOR SURFACE INTERFACIAL INTERACTIONS FOR CHEMICAL AND BIOCHEMICAL SENSING USING
Howard Katz, Kalpana Besar, Deepa Madan,
Jennifer Dailey, Weiguo Huang,
and Karim Abdou Diallo
Department of Materials Science and Engineering
Johns Hopkins University
Whiting School of Engineering
Maryland Hall 2063400, North
Charles StreetBaltimore, MD
21218-2608E-mail:
Organic, charge-modulated Field Effect Transistors (OCMFETs) have been proposed since some time and have shown so far very interesting results in a variety of sensing tasks, both for chemical and physical va-riables, as well as, more recently, for the detection of the electrical ac-tivity of cells. The core of the device is a floating gate organic transistor, capable to be operated at low voltages thanks to an ultra-thin, hybrid dielectric which can be fabricated over large areas at high yields. The sensitivity of the device is obtained by anchoring in a part of the floating gate a sensing layer (that, according to the application, may be, for in-stance, a probe molecular layer or an element dedicated to the trans-duction of a physical signal into an electrical charge as a piezoelectric layer) directly exposed to the measurement environment. In addition to the possibility of applying this measurement principle to a variety of applicative fields, by simply changing the kind of sensing layer immobi-lized on the floating gate, an important achieved result is the possibility to have precise design rules for adapting the concept to the specifica-tions imposed by the application, thus enabling the design of a dedica-ted device architecture with predictable performances. Several examp-les of this approach will be given, including also multi-modal sensing, i.e. the ability to sense several different parameters with an array of similar devices.
MULTIMODAL SENSING BY ORGANIC FIELD EFFECT DEVICES: CHEMICAL, PHYSICAL, BIOSENSING WITH THE SAME SENSING PLATFORM
Stefano Lai1, Andrea Spanu1,
Piero Cosseddu3, Mariateresa Te-
desco2,Sergio
Martinoia2, Annalisa
Bonfiglio1,3
1Department of Electrical and
Electronic Engi-neering,
University of Cagliari, Piazza
d’Armi, 09123 Cagliari, 2Depart-ment of Informa-tics, Bioenginee-
ring, Robotics and System
Engineering, University of
Genova, Via Opera Pia,
13 - 16145 Genova, 3CNR
– Institute of Nanoscience,
S3 Centre, Via Campi 213A, 41125, Modena
ItalyE-mail:
Ulrich JonasMacromolecular
ChemistryUniversity of
SiegenAdolf-Reich-
wein-Strasse 2, D-57076 Siegen
GermanyE-Mail: jonas@
chemie.uni-siegen.de
The term "reconfigurable" or "programmable" soft matter represents an emerging concept in science and technology, where the chemical, physi-cal and functional properties of materials can be switched between well-defined states by external stimulation, for example by temperature changes or by irradiation with light. Manifold examples are found in the animate nature, such as phototaxis of plants (like the head of the sunflo-wer following the sun), and at present the challenge in research aims at harnessing such powerful behavior in artificial matter by merging the specific responsive functionality of molecules with a complex structural hierarchy. Towards this aim we have synthesized a range of thermores-ponsive, water-soluble polymers with either a lower critical- (LCST) or an upper critical solution temperature (UCST) by controlled radical poly-merization methods. By means of the controlled polymerization method (RAFT and ATRP) specific end group functionalizations can be achieved. Upon variation of the temperature these polymers show a characteristic transition of their solubility and consequently of the coil dimensions in the aqueous phase, becoming soluble above their UCST, or insoluble above the LCST due to polymer coil collapse. Concomitantly, the aggre-gation state and superstructure formation (micellar and vesicular ag-gregates) depends on the external stimulus. The different polymers were also endowed with photoreactive groups that allow crosslinking upon irradiation with light. This photocrosslinking strategy enables immobili-zation of the transient state when changing external conditions. Further-more, azobenzene-containing polymers as photoresponsive systems where synthesized with the photocrosslinker units to test the possibility of simultaneous photoswitching and photocrosslinking in dependence of the irradiation wavelength.
RESPONSIVE POLYMER ARCHITECTURES – FROM HYDROGELS TO SENSORS
With the thermoresponsive system we synthesized block copolymer ar-chitectures in order to merge the LCST- and UCST behavior in one sin-gle molecule while allowing crosslink upon irradiation in their specific thermal switching states. From these polymers various hydrogel layer architectures could be realized that find application as responsive sen-sor matrix with high binding capacity in optical sensor platforms based on surface plasmon resonance or Bloch surface waves.During our stu-dies we found by dynamic light scattering that already the simple PNI-PAAm polymer showed a complex aggregation behavior, which specifi-cally depended on the end group functionalization. Details of the various synthesis strategies and characterization results will be presented, and a hypothetical model of the structure-behavior relationship will be dis-cussed based on the hydrophilic-hydrophobic balance of the end groups with the polymer chain
G. Julius VancsoUniversity of
TwenteMESA+ Research
Institute for Nano-technology
7500 AE EnschedeThe Netherlands
E-mail: [email protected]
Redox responsive natural macromolecules, including enzymes and pro-teins, play a pivotal role in life. Biomedical and other applications of ar-tificial, redox responsive polymeric systems have been limited due to li-mited access to such synthetic molecules. Emerging poly(ferrocenylsilanes) (PFS), featuring ferrocene units connected by functionalized silane groups in the main chain, constitute a versatile class of smart organometallic polymers with many useful applications ranging from biosensing, smart membranes, adhesion and friction con-trol, programmed molecular release and as “in-situ” redox reactors for controlled production of metal nanoparticles. In this lecture first a brief overview of PFS synthesis, and structure-property relations will be pro-vided. Special attention will be paid to hydrogels, and hydrogel shaping by microfluidic devices, layer-by-layer assemblies, and thin film proces-sing. Applications of PFS for electrode decoration in sensing, including electro-grafting, will be elucidated. Covalent layer-by-layer assembly yielding PFS multilayers and the use of such layers in glucose sensing will be discussed. Given that PFS has an oxidation potential of around + 0.4 V, it can reduce metal ions to metal nanoparticles when the PFS chains act as a reducing agent. We shall introduce a new metal nanopar-ticle foundry based on PFS hydrogels, which yield metal nanoparticles with sizes ranging from a few nm to tens of nm-s, without the necessity of using external reducing agents. We demonstrate the universality of the reduction capability of such hydrogels. Potential applications will be sketched, ranging from metal nanoparticle supported catalysis by utili-zing fluidic microreactors, to sensing and optoelectronics.
SMART, REDOX RESPONSIVE ORGANOMETALLIC POLYMER PLATFORMS IN SENSING AND RELEASE AND AS METAL NANOPARTICLE FOUNDRY
For a review see: X.F. Sui, X.L. Feng, M.A. Hempenius, G.J. Vancso, Redox active gels: Synthesis, structures and applications. J. Mater. Chem. B, 1(12):1658-1672, 2013.
Wolfgang Schuhmann
Analytical Che-mistry - Center for
Electrochemical Sciences (CES)
Ruhr-Universität Bochum, Univer-
sitätstr. 150D-44780 Bochum
GermanyE-mail:
wolfgang.schuhmann@
rub.de
Redox polymers are frequently used for wiring biological recognition elements such as e.g. enzymes with electrode surfaces. Evidently, for the design of biosensors, biofuel cells or biobatteries the adaptation of the redox potential of the polymer bound redox species to the formal potential of the prosthetic group in the active site of the enzyme is of high importance. Moreover, the polymer backbone structure has to be modified to allow for high mobility of the polymer-bound redox relays, swelling of the hydrogel etc.
The following aspects will be discussed:
Os-complex and phenothiazine-modified redox polymers for wiring of cellobiose dehydrogenase, glucose oxidase and PQQ-dependent glucose dehydrogenaseDesign and optimization of photobioelectrochemical devices based on photosystem 1 and photosystem 2Viologen-based redox polymers for wiring of Ni-Fe-hydrogenaseBioelectrocatalytic amplification in amperometric biosensorsSelf-powered bioelectrocatalytic devices
BIOSENSORS AND BIOFUEL CELLS BASED OF REDOX HYDROGELS
A. Toby A. JenkinsDepartment of
ChemistryUniversity of Bath
Claverton DownBath BA2 7AY
United KingdomE-mail:
The rationale of our work is to construct responsive film systems which can sense bacterial virulence factors giving a clear fluorescence / colour change and (sometimes simultaneously) release compounds which kill pathogenic bacteria. They key point here is that the systems are trigge-red by molecules released by the bacteria themselves: secreted viru-lence factors including enzymes such as hyaluronidase, peptides such as -toxin and glycolipids. In this talk I will briefly describe the impor-tant virulence factors secreted by Staphylococcus aureus and Pseudo-monas aeruginosa: specifically the Phenol Soluble Modulin (PSM) class of peptides, rhamnolipids and hyaluronidase. Three responsive film sys-tems will be briefly summarized: 1. a dispersion of lipid vesicles within a hydrogel matrix; 2. a multi-layer polymeric film utilizing cross-linked hyaluronic acid; and 3. finally a thermally triggered PNIPAM nano-gel. System 1 detects and signals the presence of membrane lytic virulence factors via a colour change or an electrochemical response, systems 2 and 3 are designed to deliver antimicrobial therapeutics into wounds.
Selected references:1. M. Laabei, W.D. Jamieson, R.C. Massey, A.T.A. Jenkins, Staphylococcus aureus Interaction with Phos-pholipid Vesicles – A New Method to Accurately Determine Accessory Gene Regulator (agr) Activity, PloS One, 2014, 9, e87270.2. M. Laabei, A.E.R. Young, A.T.A. Jenkins, In-vitro studies of Toxic Shock Toxin-1 secreting Staphylococ-cus aureus and implications for burn care in children, Pediatric Infectious Disease Journal. 2012, 31, e73-e77.3. N.T. Thet, S.H. Hong, S. Marshall, M. Laabei, A. Toby, A Jenkins, Visible, colorimetric discrimination between pathogenic strains of Staphylococcus aureus and Pseudomonas aeruginosa using fluorescent dye containing lipid vesicles, Biosensors and Bioelectronics, 2013, 41, 538 -543.4. J. Zhou, A. L. Loftus, G. Mulley, A. T. A. Jenkins, A Thin Film Detection / Response System for Patho-genic Bacteria, J. Amer. Chem. Soc. 2010, 132,, 6566–6570.5. C. James, A.L. Johnson & A.T.A. Jenkins, Antimicrobial surface grafted thermally responsive PNIPAM-co-AA nano gels, Chem. Comm. 2011, 47, 12777-12779.Analysis of Macromolecules at Electrolyte/Solid Interfaces
System 1: Phospholipid vesicles dispersed in an agarose matrix release self-quenched fluores-cein following membrane lysis by bacterial toxinsSystem 2: Two component hydrogel system with bacteriophage release following breakdown of hyaluronic acid top layer by action of secreted hyaluronidaseSystem 3: PNIPAM nano-gels release bacteriopha-ge at temperature above the LCST
STIMULI RESPONSIVE THIN FILMS
Adrian Keller,Guido
GrundmeierTechnische und
Makromolekulare Chemie
Universität Paderborn
Warburger Str. 100D-33098 Pader-
bornGermany
Email: g.grundmeier@
tc.uni-paderborn.de
The interaction of biological systems with artificial and natural materi-als plays an important role in many disciplines, ranging from medical implants to biomolecular nanotechnology. Understanding and ultimate-ly controlling the processes and reactions at these biointerfaces requi-res a complementary interface science approach that takes into ac-count the complexity of the interfaces resulting from the adsorption of organic molecules and macromolecules. Atomic Force Microscopy and optical spectroscopy allow for an in-situ analytical analysis of structu-res and processes at electrolyte/solid interfaces and of the molecular organization of biological nanomaterials. Moreover, such techniques can be combined with electrochemical analysis or performed under electrochemical control. The presentation provides an overview on how structures, forces and processes can be analyzed by means of com-bined microscopic, spectroscopic and electrochemical methods. Bio-materials interfaces and DNA-based nanostructures are selected for the illustration of the analytical approach.
ANALYSIS OF MACROMOLECULES AT ELECTROLYTE/ SOLID INTERFACES
Ana MariaOliveira-Brett
Department of Chemistry, Faculty
of Sciences and Technology,University of
Coimbra3004-535 Coimbra
PortugalE-mail:
Proteins are essential components of organisms and are involved in a wide range of biological functions. However, electrochemical studies in qualitative and quantitative analysis in proteomics of individual protein domains and mutants of proteins, not containing a centre with fast-re-versible redox reactions, are still very few. The adsorption of native proteins without prosthetic groups on a solid electrode surface is weaker due to the rigidity of the 3D-structure, which makes electron transfer between the electroactive amino acids in the interior of the proteins and the electrode surface more difficult. Only ty-rosine, tryptophan, histidine, cysteine and methionine residues are oxi-dized on carbon electrodes in aqueous solution and all present a pH-dependent electron transfer mechanism.Protein direct electron transfer reactions at carbon electrodes, glassy carbon and boron doped diamond electrode surfaces, of the enzyme peptide methionine sulfoxide reductase A (MsrA), and monoclonal anti-body rituximab (RTX), were investigated. MsrA is a ubiquitous protein, highly conserved, one of the major targets of reactive oxygen species, an antioxidant repair enzyme which reduces oxidized methionine to methi-onine, preventing irreversible protein damage and, as a consequence, extending the organism's life span. RTX is a human/murine chimeric monoclonal antibody that specifically targets the transmembrane prote-in CD20 of B cells, already approved for the treatment of low-grade non-Hodgkin's B cell lymphomas, and the RTX-DNA interaction was also in-vestigated using a dsDNA-electrochemical biosensor. The interaction of proteins with solid electrode surfaces is not only a fundamental phenomenon but also a key to several important and novel applications in biosensors, biotechnology, medical devices and drug-delivery schemes.
PROTEIN ELECTROCHEMICAL OXIDATION
Diabetes is characterized by insufficient insulin plasma level to meet the organism demand. In type 1 diabetes, absolute deficiency of insulin production results from massive auto-immune destruction of pancrea-tic beta cells. For this reason, the main therapy consists in delivering exogenous insulin. The treatment methods require numerous daily in-jections of insulin administered by subcutaneous needle injection, insu-lin pen and catheters connected to insulin pumps. These methods are however both painful and inconvenient. There is thus an increasing de-mand for the design of new insulin administration systems and this has led to the investigations of oral, nasal, buccal, pulmonary, rectal, ocular and transdermal routes. Transdermal delivery of insulin has been re-cently proposed as a viable alternative allowing the controlled release of insulin over time together with high patience compliance.1 While transdermal delivery is limited by the low permeability of the stratum corneum, the skin’s outermost layer, skin permeation can be enhanced through electrical activation. In this presentation, the advantage of flexible electrodes modified with reduced graphene (rGO) and loaded with insulin,2-3 to electrically trig-ger insulin release over time will be presented. A special focus will be on the development of insulin-impregnated conductive matrixes and the influence of potential and current on the biological activity of re-leased insulin.
References :1. S. I. Hadebe, P. S. Nhubane, M. R. Serumula, C. T. Musabayane, PLOS one, 2014, 9, e1014461.2. I. Kaminska, M. R. Das, Y. Coffinier; J. Niedziółka-Jönsson, P. Woisel, M. Opallo, S. Szunerits, R Boukherroub, Chem. Commun. 2012, 48, 1221-1223 (cover page)3. K. Turcheniuk, M. Khanal, A. Montorina, P. Subramanian, A. Barras, V. Zaitsev, V. Kuncer, A. Leca, A. Martoriati, K. Cailliau, J.-F. Bodart, R. Boukherroub, S. Szunerits RSC Adv. 2014, 4 (2) 865-875.
ELECTROCHEMICAL DELIVERY PLATFORM OF INSULIN ON DEMAND
Sabine SzuneritsInstitut de Recherche
InterdisciplinaireIRI, USR-3078,
Parc de la Haute Borne
50 avenue de Hal-ley, BP 70478
59658 Villeneuve d’AscqFranceEmail :
Zhenan BaoDepartment of Chemical Engineering
Stanford Univer-sity
381, North South Mall
Stanford, CA 94305
E-mail: [email protected]
Organic and carbon nano materials are attractive for low cost electronic units for electronic skin as well as medicinal, food storage, and environ-mental monitoring applications. The ability to couple the sensory electri-cal output with on-chip signal processing can overcome the need for bulky, expensive equipment typically required for most optical detection methods. In this talk, I will present recent progress in applications of these materials and devices for skin-inspired sensors and electronics.
SKIN INSPIRED ELECTRONICS BASED ON ORGANIC MATERIALS
Celiac disease (CD) is a gluten-dependent autoimmune disorder occur-ring in individuals carrying the human leucocyte antigen (HLA) DQ2-DQ8 molecules, with a prevalence of 1% in the general population. The clinical condition of CD vary from mild to severe, and some patients with celiac disease can be asymptomatic for years. The later the diagnosis of CD, the more likelihood of serious illness and excess mortality. Early diagnosis and treatment with gluten-free diet (GFD), reduces mortality and the prevalence of CD-associated disorders. Although definitive dia-gnosis of CD is still based on histological changes in small intestinal mucosa, serological test for CD screening based on detection of anti-transglutaminase type-2 antibodies (anti-TG) are less invasive, with ex-cellent sensitivity (98%) and specificity (95%). Rapid tests might greatly help the physician to make a preliminary diagnosis of CD in poor coun-tries where diarrheal disease and malnutrition are common. In this contest, making diagnosis of CD easier thanks to the use of suitable biosensors would make a significant contribution to reduce morbidity and mortality, particularly when the CD-diagnosis is not yet considered. With this goal, in this communication we present the development of a sensitive and specific immunosensor based on functionalized ensemb-les of nanoelectrodes (NEEs) prepared by electroless deposition of Au in pores of track-etched polycarbonate (PC) filter membrane. The sensor employs tTG as biorecognition layer which is immobilized on the PC of the NEEs by exploiting the high affinity of PC for proteins. The captured analyte, namely, anti-TG, is then reacted with a secondary antibody la-beled alternatively with a redox enzyme or with Ru(bpy)32+; we used the former label for electrochemical (voltammetric) detection and the latter for electrochemically induced luminescent detection. Comparison bet-ween the two detection schemes is discussed also on the basis of the results achieved by analyzing human serum samples.
Henok B. Habtamua2, Milica
Senticb3, Luigina De Leod, Tarcisio
Notd, Neso Sojicb, Paolo Ugo1
1Department of Molecular
Sciences and Nanosystems,
University Ca’Foscari of
Venice, S. Marta 2137, 30123 Venice, Italy
2 Institut des Sciences
Moleculaires, University of
Bordeaux, ENSCBP. 33607 Pessac, France
3University of Belgrade, Faculty
of Chemistry, 11000 Belgrade,
Serbia4Institute of Child
Health IRCCS “Burlo Garofolo”,
34100, Trieste, Italy
Email: [email protected]
HIGHLY SENSITIVE ELECTROCHEMICAL AND ELECTROCHE-MILUMINESCENT DETECTION OF CELIAC DISEASE BIOMAR-KERS AT GOLD NANOELECTRODE ENSEMBLES
