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Sayhi, M., Ouerghi, O., Belgacem, K., Arbi, M., Tepeli, Y., Ghram, A., . . . Diouani, M. F. (2018). Electrochemical detection of influenza virus H9N2 based on both immunomagnetic extraction and gold catalysis using an immobilization-free screen printed carbon microelectrode. Biosensors & bioelectronics, 107, 170-177
Open this publication in new window or tab >>Electrochemical detection of influenza virus H9N2 based on both immunomagnetic extraction and gold catalysis using an immobilization-free screen printed carbon microelectrode
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2018 (English)In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 107, p. 170-177Article in journal (Refereed) Published
Abstract [en]

Influenza is a viral infectious disease considered as a source of many health problems and enormous socioeconomic disruptions. Conventional methods are inadequate for in-field detection of the virus and generally suffer from being laborious and time-consuming. Thus, studies aiming to develop effective alternatives to conventional methods are urgently needed. In this work, we developed an approach for the isolation and detection of influenza A virus subtype H9N2. For this aim, two specific influenza receptors were used. The first, anti-matrix protein 2 (M2) antibody, was attached to iron magnetic nanoparticles (MNPs) and used for the isolation of the virus from allantoic fluid. The second biomolecule, Fetuin A, was attached to an electrochemical detectable label, gold nanoparticles (AuNPs), and used to detect the virus tacking advantage from fetuin-hemagglutinin interaction. The MNP-Influenza virus-AuNP formed complex was isolated and treated by an acid solution then the collected gold nanoparticles were deposited onto a screen printed carbon electrode. AuNPs catalyzes the hydrogen ions reduction in acidic medium while applying an appropriate potential, and the generated current signal was proportional to the virus titer. This approach allows the rapid detection of influenza virus A/H9N2 at a less than 16 HAU titer.

Keywords
Influenza Virus A, H9N2, Biosensors, Nanoparticles, Chronoamperometry
National Category
Analytical Chemistry Nano Technology
Research subject
Chemistry with specialization in Analytical Chemistry; Chemistry with specialization in Bioorganic Chemistry; Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
urn:nbn:se:uu:diva-346280 (URN)10.1016/j.bios.2018.02.018 (DOI)000428006900020 ()29455027 (PubMedID)
Funder
EU, Horizon 2020, 645758
Available from: 2018-03-16 Created: 2018-03-16 Last updated: 2018-06-20Bibliographically approved
Geremariam Welearegay, T., Cindemir, U., Österlund, L. & Ionescu, R. (2018). Fabrication and characterisation of ligand-functionalised ultrapure monodispersed metal nanoparticle nanoassemblies employing advanced gas deposition technique. Nanotechnology, 29(6), Article ID 065603.
Open this publication in new window or tab >>Fabrication and characterisation of ligand-functionalised ultrapure monodispersed metal nanoparticle nanoassemblies employing advanced gas deposition technique
2018 (English)In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 29, no 6, article id 065603Article in journal (Refereed) Published
Abstract [en]

Here, we report for the first time the fabrication of ligand-functionalised ultrapure monodispersed metal nanoparticles (Au, Cu, and Pt) from their pure metal precursors using the advanced gas deposition technique. The experimental conditions during nanoparticle formation were adjusted in order to obtain ultrafine isolated nanoparticles on different substrates. The morphology and surface analysis of the as-deposited metal nanoparticles were investigated using scanning electron microscopy, x-ray diffraction and Fourier transform infra-red spectroscopy, which demonstrated the formation of highly ordered pure crystalline nanoparticles with a relatively uniform size distribution of similar to 10 nm (Au), similar to 4 nm (Cu) and similar to 3 nm (Pt), respectively. A broad range of organic ligands containing thiol or amine functional groups were attached to the nanoparticles to form continuous networks of nanoparticle-ligand nanoassemblies, which were characterised by scanning electron microscopy and x-ray photoelectron spectroscopy. The electrical resistance of the functional nanoassemblies deposited in the gap spacing of two microfabricated parallel Au electrodes patterned on silicon substrates ranged between tens of k Omega and tens of M Omega, which is suitable for use in many applications including (bio)chemical sensors, surface-enhanced Raman spectroscopy and molecular electronic rectifiers.

Place, publisher, year, edition, pages
IOP PUBLISHING LTD, 2018
Keywords
metal nanoparticles, monodispersed, advanced gas deposition, molecularly-capped metal nanoparticles, self-assembled monolayers
National Category
Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-341557 (URN)10.1088/1361-6528/aa9f65 (DOI)000419631700003 ()29206108 (PubMedID)
Available from: 2018-02-13 Created: 2018-02-13 Last updated: 2018-03-28Bibliographically approved
Haas, J., Vargas Catalan, E., Piron, P., Nikolajeff, F., Österlund, L., Karlsson, M. & Mizaikoff, B. (2018). Polycrystalline diamond thin-film waveguides for mid-infrared evanescent field sensors. ACS Omega, 3, 6190-6198
Open this publication in new window or tab >>Polycrystalline diamond thin-film waveguides for mid-infrared evanescent field sensors
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2018 (English)In: ACS Omega, ISSN 2470-1343, Vol. 3, p. 6190-6198Article in journal (Refereed) Published
National Category
Engineering and Technology Analytical Chemistry
Identifiers
urn:nbn:se:uu:diva-346523 (URN)10.1021/acsomega.8b00623 (DOI)
Available from: 2018-03-19 Created: 2018-03-19 Last updated: 2018-06-23
Mattsson, A. & Österlund, L. (2017). Co-adsorption of oxygen and formic acid on rutile TiO2 (110) studied by infrared reflection-absorption spectroscopy. Surface Science, 663, 47-55
Open this publication in new window or tab >>Co-adsorption of oxygen and formic acid on rutile TiO2 (110) studied by infrared reflection-absorption spectroscopy
2017 (English)In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 663, p. 47-55Article in journal (Refereed) Published
Abstract [en]

Adsorption of formic acid and co-adsorption with oxygen have been investigated on the rutile TiO2(110) surface using p- and s-polarized infrared reflection-absorption spectroscopy (IRRAS) at O2 exposures between 45 L to 8100 L and at temperatures between 273 K and 343 K. On the clean surface formic acid dissociates into a formate ion (formate) and a proton. Formate binds to two five-fold coordinated Ti atoms in the troughs along the [001] direction, and the proton binds to neighboring bridging O atoms. Exposure of adsorbed formate to O2 leads to a decrease in the asymmetric νas(OCO) band at 1532 cm−1 and to the concomitant formation of a new vibration band at 1516 cm−1. From the s-and p-polarized IRRAS measurements performed at different O2 exposures, surface pre-treatments and substrate temperatures, and by comparisons with previous reports, we conclude that the new species is a bidentate surface hydrogen carbonate, which is formed by reaction between formate and oxygen adatoms on the surface. The σv reflection plane of the surface hydrogen carbonate molecule is oriented along the [001] direction, i.e. the same direction as the adsorbed formate molecule. On the clean TiO2(110) surface exposed to O2 prior to formic acid adsorption, similar results are obtained. The reaction rate to form surface hydrogen carbonate from formate is found to follow first-order kinetics, with an apparent activation energy of Er=0.25 eV.

National Category
Engineering and Technology
Research subject
Engineering Science with specialization in Materials Science
Identifiers
urn:nbn:se:uu:diva-332994 (URN)10.1016/j.susc.2017.04.012 (DOI)
Funder
Swedish Research Council, 2010-3514
Available from: 2017-12-01 Created: 2017-12-01 Last updated: 2017-12-04Bibliographically approved
Lebrun, D. & Österlund, L. (2017). Demonstration of Slow Photon Chemistry on Multilayer Inverse Opals. Science of Advanced Materials, 9(11), 1947-1952
Open this publication in new window or tab >>Demonstration of Slow Photon Chemistry on Multilayer Inverse Opals
2017 (English)In: Science of Advanced Materials, ISSN 1947-2935, E-ISSN 1947-2943, Vol. 9, no 11, p. 1947-1952Article in journal (Refereed) Published
Abstract [en]

We demonstrate the use of atomic layer deposited multilayered alumina/titania photonic crystals for stearicacid (SA) degradation using broadband light illumination. The degradation of SA was monitored every 15 minutes by Fourier transform infrared spectroscopy, using a simple rotation of the sample holder to switchbetween light source and infrared probing beam. We analyzed four samples with different photonic bandgap(PBG) positions, from 397 to 372 nm, with different titania layer thicknesses, but otherwise prepared in identicalmanner. With this approach the photonic efficiency (PE) could readily be calculated without having to considerdifferent sample preparation procedure. We found that a sample with a high-energy edge of the PBG positionoverlapping with the electronic bandgap position of titania (Eg∼ 385 nm) and the highest photon power of ourlight source had the highest PE = 0.002. Comparison with the other samples shows that the slow photon effectapparent at the PBG edge can explain the higher PE, and suggest that bandgap engineering of multilayerphotonic materials is a practically viable method to improve the efficiency of a photocatalyst.

Place, publisher, year, edition, pages
United States of America: , 2017
Keywords
Photocatalysis, Photonic Crystals, Slow Photon, Titania, Stearic Acid.
National Category
Nano Technology
Research subject
Engineering Science with specialization in Materials Science
Identifiers
urn:nbn:se:uu:diva-305260 (URN)10.1166/sam.2016.2833 (DOI)000419754900011 ()
Funder
Swedish Research Council, 2010- 3514
Available from: 2016-10-13 Created: 2016-10-13 Last updated: 2018-02-21Bibliographically approved
Cindemir, U., Trawka, M., Smulko, J., Granqvist, C.-G., Österlund, L. & Niklasson, G. . (2017). Fluctuation-enhanced and conductometric gas sensing with nanocrystalline NiO thin films: A comparison. Sensors and actuators. B, Chemical, 242, 132-139
Open this publication in new window or tab >>Fluctuation-enhanced and conductometric gas sensing with nanocrystalline NiO thin films: A comparison
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2017 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 242, p. 132-139Article in journal (Refereed) Published
Abstract [en]

Nanocrystalline thin films of NiO were prepared by advanced reactive gas deposition, and their responses to formaldehyde, ethanol and methane gases were studied via fluctuation-enhanced and conductometric methods Thin films with thicknesses in the 200–1700-nm range were investigated in as-deposited form and after annealing at 400 and 500◦C. Morphological and structural analyses showed porous deposits with NiO nanocrystals having face-centered cubic structure. Quantitative changes in frequency-dependent resistance fluctuations as well as in DC resistance were recorded upon exposure to formaldehyde, ethanol and methane at 200◦C. The response to formaldehyde was higher than that to ethanol while the response to methane was low, which indicates that the NiO films exhibit significant selectivity towards different gaseous species. These results can be reconciled with the fact that formaldehyde has a nucleophilic group, ethanol is an electron scavenger, and methane is hard to either reduce or oxidize. The gas-induced variations in DC resistance and resistance fluctuations were in most cases similar and consistent.

National Category
Nano Technology Engineering and Technology
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-307575 (URN)10.1016/j.snb.2016.11.015 (DOI)000393267700018 ()
Funder
EU, European Research CouncilEU, Horizon 2020, 645758
Available from: 2016-11-17 Created: 2016-11-17 Last updated: 2017-11-02
Johansson, M. B., Mattsson, A., Lindquist, S.-E., Niklasson, G. A. & Österlund, L. (2017). The Importance of Oxygen Vacancies in Nanocrystalline WO3−x ThinFilms Prepared by DC Magnetron Sputtering for Achieving High Photoelectrochemical Efficiency. The Journal of Physical Chemistry C, 121(13), 7412-7420
Open this publication in new window or tab >>The Importance of Oxygen Vacancies in Nanocrystalline WO3−x ThinFilms Prepared by DC Magnetron Sputtering for Achieving High Photoelectrochemical Efficiency
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2017 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 121, no 13, p. 7412-7420Article in journal (Refereed) Published
Abstract [en]

The photoelectrochemical properties of tungsten oxide thinfilms with different stoichiometry (WO3−x) and thickness were investigated.The films were sputtered in O2/Ar gas (ratio 0.43) on glass substrates coatedwith fluorine-doped tin dioxide at two sputter pressures, Ptot = 10 and 30mTorr, yielding O/W ratios of the films, averaged over three samples, of 2.995and 2.999 (x ∼ 0.005 and x ∼ 0.001), respectively. The films were characterizedby X-ray diffraction, scanning electron microscopy, and spectrophotometry.The 10 mTorr samples showed large absorption in the near-infrared (NIR)range, whereas the 30 mTorr samples had a small absorption in this region. Theconcentration of oxygen vacancy band gap states was estimated from cyclicvoltammetry and was found to correlate with the optical absorption in the NIRregion. The incident photon to current efficiency for illumination from theelectrolyte side (IPCEEE) and substrate electrode side (IPCESE) showed higherefficiency for the more stoichiometric films, indicating that oxygen vacancies in the band gap act as recombination centers.Surprisingly high values of IPCEEE and IPCESE were found, and it was concluded that efficient charge separation and transporttake place almost throughout the entire film even for film electrodes as thick as 2 μm. Analysis of the spectral distribution of thephotoresponse (action spectra) using an extended Gärtner−Butler model to calculate the IPCE for front-side and back-sideillumination was performed and showed that the diffusion length is large, of the order of the depletion layer thickness.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2017
Keywords
Photoelectrochemistry, WO3, Oxygen vacancy, thin films
National Category
Physical Chemistry Engineering and Technology
Research subject
Chemistry with specialization in Physical Chemistry; Engineering Science with specialization in Materials Science
Identifiers
urn:nbn:se:uu:diva-319249 (URN)10.1021/acs.jpcc.7b00856 (DOI)000398881800040 ()
Funder
Swedish Research Council, VR-2010-3514Swedish Research Council, VR-2011-3940
Available from: 2017-04-02 Created: 2017-04-02 Last updated: 2017-05-15Bibliographically approved
Stefanov, B., Niklasson, G. A., Granqvist, C.-G. & Österlund, L. (2016). Gas-phase photocatalytic activity of sputter-deposited anatase TiO2 films: Effect of <001> preferential orientation, surface temperature and humidity. Journal of Catalysis, 335, 187-196
Open this publication in new window or tab >>Gas-phase photocatalytic activity of sputter-deposited anatase TiO2 films: Effect of <001> preferential orientation, surface temperature and humidity
2016 (English)In: Journal of Catalysis, ISSN 0021-9517, E-ISSN 1090-2694, Vol. 335, p. 187-196Article in journal (Refereed) Published
Abstract [en]

We present a systematic in situ study of the environmental reaction conditions on the photocatalytic activity of sputter deposited anatase TiO2 films with controlled amounts of preferential <001> orientation. In particular, the effects of relative humidity (RH) and substrate temperature ( ) are investigated. It is found that {001} facets, which are present in higher abundance on highly oriented samples, exhibit an order of magnitude higher reactivity for gas-phase photocatalytic oxidation of the indoor air pollutant acetaldehyde (CH3CHO) than {101} facets do, and a functional dependence of the reaction rate on facet orientation is determined. It is proposed that water adsorbed on the film contributes with two counteracting effects on the photocatalytic activity: (i) It provides hole acceptors to complete the photo-induced redox cycle and subsequent OH– radical formation for pollutant degradation, and (ii) it creates a diffusion barrier between the catalyst interface and pollutant molecules adsorbed in the water layer. As a consequence, increasing  at high RH has the beneficial effect of removing excess water and reducing the diffusion barrier, thereby improving the photocatalytic activity. A comparison is also made with a commercial anatase TiO2 film, with less developed surface crystallinity and random facet distribution, where the improvement is even more pronounced. Films with a higher degree of orientation exhibit much more stable performance over a range of operating conditions, which suggests that it is possible to tune the effects of water and exposed facet orientation to achieve optimum activity and making TiO2 films amenable to a larger (RH, ) parameter space for practical applications.

National Category
Inorganic Chemistry Condensed Matter Physics Chemical Engineering Nano Technology
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-265055 (URN)10.1016/j.jcat.2015.12.002 (DOI)000371098200018 ()
External cooperation:
Projects
GRINDOOR
Funder
EU, FP7, Seventh Framework Programme, FP7/2007-2013
Available from: 2015-10-21 Created: 2015-10-21 Last updated: 2017-12-01Bibliographically approved
Mattsson, A. & Österlund, L. (2016). Infrared Reflection-Absorption Spectroscopy Study of the Interaction between O2 and Formic Acid on Rutile TiO2 (110) Surfaces. In: : . Paper presented at 2016 MRS spring meeting & exhibit.
Open this publication in new window or tab >>Infrared Reflection-Absorption Spectroscopy Study of the Interaction between O2 and Formic Acid on Rutile TiO2 (110) Surfaces
2016 (English)Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

Formic acid adsorption on rutile TiO2(110) single crystals exposed to different oxygen partial pressures have been investigated with infrared reflection-absorption spectroscopy (IRRAS) employing p- and s-polarized light incident along the [001] crystal direction at a temperatures between 273K and 303K. IRRAS spectra, prior to oxygen exposure, shows that formic acid dissociates upon adsorption and binds to the surface as bridging formate species with the symmetric νs(OCO) and asymmetric νas(OCO) peak at 1360 and 1531 cm-1, respectively. A new asymmetric νas(OCO) band at 1517 cm-1develops in the presence of O2, which is correlated with the O2 partial pressure, whereas no changes is seen in the symmetric νs(OCO) band. At low O2 pressures(<1 ×10-7mbar), this band is not detectable within 3 h of O2 exposure. At higher O2pressures, 5 ×10-7 mbar, the band starts to develop, and at 1 ×10-6 mbar, a pronounced band develops after 30 min exposure. The O2 induced band at 1517 cm-1 does not disappear as the O2 gas is removed, suggesting that a stable chemical modification of adsorbed formate molecules. No changes were observed in the s-polarized IRRAS spectra with O2 exposure, showing that there is no rotation of the formate molecules in the plane of the surface. The appearance of the new νas(OCO) band are consistent with a model where O2 dissociated to form O adatoms bonded to the Ti5c atoms, which interact with bridging formate molecules bonded along the [001] direction. The relationship between the oxygen partial pressure and the formation of this new band is due to the increased larger interaction between the surface and the oxygen with increase pressure or an increased oxygenation of formate. Our results provide new insight into the interaction between O2and TiO2surfaceat elevated pressures relevant for practical applications.

National Category
Engineering and Technology
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-283107 (URN)
External cooperation:
Conference
2016 MRS spring meeting & exhibit
Funder
Swedish Research Council, 2015-04757
Available from: 2016-04-11 Created: 2016-04-11 Last updated: 2016-08-30Bibliographically approved
Lopez-Lorente, A., Wang, P., Sieger, M., Vargas Catalan, E., Karlsson, M., Nikolajeff, F., . . . Mizaikoff, B. (2016). Mid-infrared thin-film diamond waveguides combined with tunable quantum cascade lasers for analyzing the secondary structure of proteins. Physica Status Solidi (a) applications and materials science, 213(8), 2117-2123
Open this publication in new window or tab >>Mid-infrared thin-film diamond waveguides combined with tunable quantum cascade lasers for analyzing the secondary structure of proteins
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2016 (English)In: Physica Status Solidi (a) applications and materials science, ISSN 1862-6300, E-ISSN 1862-6319, Vol. 213, no 8, p. 2117-2123Article in journal (Refereed) Published
Abstract [en]

Diamond has excellent optical properties including broadband transmissivity, low self-absorption, and a high refractive index, which have prompted its use for optical sensing applications. Thin-film diamond strip waveguides (DSWGs) combined with tunable quantum cascade lasers (tQCLs) providing an emission wavelength range of 5.78-6.35 mu m (1735-1570 cm(-1)) have been used to obtain mid-infrared (MIR) spectra of proteins, thereby enabling the analysis of their secondary structure via the amide I band. Three different proteins were analyzed, namely bovine serum albumin (BSA), myoglobin, and gamma-globulin. The secondary structure of BSA and myoglobin has a major contribution of a-helices, whereas gamma-globulins are rich in beta-sheet structures, which is reflected in the amide I band. Acomparison of the spectra obtained via the combination of the tQCL and DSWG with spectra obtained using conventional Fourier transform infrared (FTIR) spectroscopy and a commercial diamond attenuated total reflection (ATR) element has been performed. It is shown that the main features evident in FTIR-ATR spectra are also obtained using tQCL-DSWG sensors.

National Category
Other Physics Topics Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-282255 (URN)10.1002/pssa.201600134 (DOI)000385223900016 ()
Available from: 2016-04-04 Created: 2016-04-04 Last updated: 2017-11-30Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-0296-5247

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