umu.sePublications
Change search
Refine search result
1 - 5 of 5
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1. Butina, Karen
    et al.
    Löffler, Susanne
    Rhen, Mikael
    Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR). Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
    Richter-Dahlfors, Agneta
    Electrochemical sensing of bacteria via secreted redox active compounds using conducting polymers2019In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 297, article id 126703Article in journal (Refereed)
    Abstract [en]

    Bacterial infections and antibiotic resistance represent major global threats to public health. Current diagnostics use culture based assays that are reliable but slow, hence appealing for new rapid methods. Here we describe redox sensing as a novel concept for rapid, label-free detection of bacteria. We utilize a two-electrode poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) based sensor for detection of bacterially secreted redox-active compounds. Using purified redox-active compounds, we show the ability of the sensor to detect and quantify compounds in micromolar concentrations within minutes. When applied for detection and quantification of Salmonella, we show that secreted, low molecular weight redox compounds cause reduction of the PEDOT:PSS electrode. A potential role of redox sensing in infection diagnostics was demonstrated as uropathogenic strains of E. coli., Staphylococcus, Enterococcus, Pseudomonas, Proteus, and Klebsiella spp., major causes of complicated urinary tract infections, were successfully detected in complex media or processed urine. Since numerous bacterial species are capable of extracellular electron transfer, redox sensing may find use as a generic method for bacterial detection with applications in research laboatories, the clinic and industry alike.

  • 2. Kukkola, Jarmo
    et al.
    Mohl, Melinda
    Leino, Anne-Riikka
    Maklin, Jani
    Halonen, Niina
    Shchukarev, Andrey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Konya, Zoltan
    Jantunen, Heli
    Kordas, Krisztian
    Room temperature hydrogen sensors based on metal decorated WO3 nanowires2013In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 186, p. 90-95Article in journal (Refereed)
    Abstract [en]

    The emerging hydrogen economy has created a demand for the development of improved hydrogen sensors operating at room temperature. In this work, we present hydrogen detectors based on metal decorated WO3 nanowires that were able to detect 1000 ppm of H-2, even at room temperature (30 degrees C), with relatively short recovery time and high sensitivity. The nanowires were synthesized by a hydrothermal process and decorated with PdO and PtOx nanoparticles by decomposition of Pd(acac)(2) and Pt(acac)(2) precursors. The gas responses were tested for H-2, NO, H2S and CO analyte gases in an air buffer at 150,200 and 250 degrees C (H-2 also at 30,70 and 130 degrees C).

  • 3. Kukkola, Jarmo
    et al.
    Mäklin, Jani
    Halonen, Niina
    Kyllönen, Teemu
    Tóth, Géza
    Szabó, Maria
    Shchukarev, Andrey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Mikkola, Jyri-Pekka
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Jantunen, Heli
    Kordás, Krisztián
    Gas sensors based on anodic tungsten oxide2011In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 153, no 2, p. 293-300Article in journal (Refereed)
    Abstract [en]

    Nanostructured porous tungsten oxide materials were synthesized by the means of electrochemical etching (anodization) of tungsten foils in aqueous NaF electrolyte. Formation of the sub-micrometer size mesoporous particles has been achieved by infiltrating the pores with water. The obtained colloidal anodic tungsten oxide dispersions have been used to fabricate resistive WO3 gas sensors by drop casting the sub-micrometer size mesoporous particles between Pt electrodes on Si/SiO2 substrate followed by calcination at 400 °C in air for 2 h. The synthesized WO3 films show slightly nonlinear current–voltage characteristics with strong thermally activated carrier transport behavior measured at temperatures between −20 °C and 280 °C. Gas response measurements carried out in CO, H2, NO and O2 analytes (concentration from 1 to 640 ppm) in air as well as in Ar buffers (O2 only in Ar) exhibited a rapid change of sensor conductance for each gas and showed pronounced response towards H2 and NO in Ar and air, respectively. The response of the sensors was dependent on temperature and yielded highest values between 170 °C and 220 °C.

  • 4. Moreno-Guzman, Maria
    et al.
    Garcia-Carmona, Laura
    Molinero-Fernandez, Agueda
    Cava, Felipe
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Lopez Gil, Miguel Angel
    Escarpa, Alberto
    Bi-enzymatic biosensor for on-site, fast and reliable electrochemical detection of relevant D-amino acids in bacterial samples2017In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 242, p. 95-101Article in journal (Refereed)
    Abstract [en]

    In this work, a bi-enzymatic biosensor allowed the total content of D-amino acids (DAAs) determination in highly relevant matrices involving bacteria. The strategy is based on the unique coimmobilization of D-amino acid oxidase (DAAO) and horseradish peroxidase (HRP) enzymes onto a multi-walled carbon nanotubes (MWCNTs) and gold nanoparticles (AuNPs) modified screen-printed electrode (SPCE). The greater amount of AuNPs deposited and hence the greater loading of both enzymes was observed when they were deposited after the activation of the carboxylated MWCNTs with EDC/Sulfo-NHS chemistry. These platforms provided a fast (300s) and selective quantification of DAAs with excellent precision (RSD < 5%) and accuracy (Recoveries 100-104%) in bacterial samples. Collectively, the electrochemical bi-enzymatic biosensor become an universal, fast, sensitive and easy-to-use approach to determine total content of DAAs in complex matrices.

  • 5.
    Sandström, K. J. Mattias
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational Medicine. Cranfield Biotechnology Centre, Cranfield University, UK; Department of Chemistry, National Institute for Working Life, Umeå, Sweden.
    Newman, Jeffrey
    Cranfield Biotechnology Centre, Cranfield University, UK.
    Sunesson, Anna-Lena
    Department of Chemistry, National Institute for Working Life, Umeå, Sweden.
    Levin, Jan-Olof
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational Medicine. Department of Chemistry, National Institute for Working Life, Umeå, Sweden.
    Turner, Anthony P. F.
    Cranfield Biotechnology Centre, Cranfield University, UK.
    Amperometric biosensor for formic acid in air2000In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 70, no 1–3, p. 182-187Article in journal (Refereed)
    Abstract [en]

    The possibility of developing a simple, inexpensive and specific personal passive “real-time” air sampler incorporating a biosensor for formic acid was investigated. The sensor is based on the enzymatic reaction between formic acid and formate dehydrogenase (FDH) with nicotinamide adenine dinucleotide (NAD+) as a co-factor and Meldola's blue as mediator. An effective way to immobilise the enzyme, co-factor and Meldola's blue on screen-printed, disposable, electrodes was found to be in a mixture of glycerol and phosphate buffer covered with a gas-permeable membrane. Steady-state current was reached after 4–15 min and the limit of detection was calculated to be below 1 mg/m3. However, the response decreased by 50% after storage at −15°C for 1 day.

1 - 5 of 5
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf