A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Selected papers from the latest issue:
Using the nanoimprint-in-metal method to prepare corrugated metal structures for plasmonic biosensors through both surface plasmon resonance and index-matching effects
25 January 2012, 01:10:19
Publication year: 2012
Source: Biosensors and Bioelectronics, Available online 24 January 2012
Chen-Chieh Yu, Kuan-Hung Ho, Hsuen-Li Chen, Shang-Yu Chuang, Shao-Chin Tseng, ...
In this study, we prepared metallic corrugated structures for use as highly sensitive plasmonic sensors. Relying on the direct nanoimprint-in-metal method, fabrication of this metallic corrugated structure was readily achieved in a single step. The metallic corrugated structures were capable of sensing both surface plasmon resonance (SPR) wavelengths and index-matching effects. The corrugated Au films exhibited high sensitivity (ca. 800 nm/RIU), comparable with or even higher than those of other reported SPR-based sensors. Because of the unique index-matching effect, refractometric sensing could also be performed by measuring the transmission intensity of the Au/substrate SPR mode—conveniently, without a spectrometer. In the last, we demonstrated the corrugated Au film was capable of sensing biomolecules, revealing the ability of the structure to be a highly sensitive biosensor
Source: Biosensors and Bioelectronics, Available online 24 January 2012
Chen-Chieh Yu, Kuan-Hung Ho, Hsuen-Li Chen, Shang-Yu Chuang, Shao-Chin Tseng, ...
In this study, we prepared metallic corrugated structures for use as highly sensitive plasmonic sensors. Relying on the direct nanoimprint-in-metal method, fabrication of this metallic corrugated structure was readily achieved in a single step. The metallic corrugated structures were capable of sensing both surface plasmon resonance (SPR) wavelengths and index-matching effects. The corrugated Au films exhibited high sensitivity (ca. 800 nm/RIU), comparable with or even higher than those of other reported SPR-based sensors. Because of the unique index-matching effect, refractometric sensing could also be performed by measuring the transmission intensity of the Au/substrate SPR mode—conveniently, without a spectrometer. In the last, we demonstrated the corrugated Au film was capable of sensing biomolecules, revealing the ability of the structure to be a highly sensitive biosensor
Highlights
► Metallic corrugated structure is prepared as highly sensitive plasmonic sensors ► It can sense both surface plasmon resonance wavelength and index-matching effect ► A high sensitivity of 800 nm/RIU is achieved according to resonance wavelength shift ► Besides, the linear response of resonance intensity is adopted for sensing as well ► In the last, the structure demonstrates the ability to be a sensitive biosensorElectrical detection of Biomolecular adsorption on Sprayed Graphene Sheets
25 January 2012, 01:10:19
Publication year: 2012
Source: Biosensors and Bioelectronics, Available online 24 January 2012
Tamon R. Page, Yuhei Hayamizu, Christopher R. So, Mehmet Sarikaya
The binding affinities of graphite-binding peptides to a graphite surface were electrically characterized using sprayed graphene field effect transistors (SGFETs) fabricated with solution exfoliated graphene. The binding affinities of these peptides were also characterized using atomic force microscopy (AFM) and mechanically exfoliated graphene field effect transistors (GFETs) to confirm the validity of the SGFET platform. Binding constants obtainedviaGFET and AFM were comparable with those observed using SGFETs. The sprayed graphene film serves as a scalable platform to study biomolecular adsorption to graphitic surfaces
Source: Biosensors and Bioelectronics, Available online 24 January 2012
Tamon R. Page, Yuhei Hayamizu, Christopher R. So, Mehmet Sarikaya
The binding affinities of graphite-binding peptides to a graphite surface were electrically characterized using sprayed graphene field effect transistors (SGFETs) fabricated with solution exfoliated graphene. The binding affinities of these peptides were also characterized using atomic force microscopy (AFM) and mechanically exfoliated graphene field effect transistors (GFETs) to confirm the validity of the SGFET platform. Binding constants obtainedviaGFET and AFM were comparable with those observed using SGFETs. The sprayed graphene film serves as a scalable platform to study biomolecular adsorption to graphitic surfaces
Highlights
► We fabricated graphene field effect transistors with solution exfoliated graphene ► The transistor enables us to characterize bio-molecular adsorption electrically ► We studied solid-binding peptides as a molecular calibration tool ► This sensor responded to the peptides comparably with conventional graphene sensors ► The sensorgrams are verified by atomic force microscopyEvaluation of permselective membranes for optimization of intracerebral amperometric glutamate biosensors
25 January 2012, 01:10:19
Publication year: 2012
Source: Biosensors and Bioelectronics, Available online 24 January 2012
N.Wahono, S. Qin, P. Oomen, T.I.F. Cremers, M.G. de Vries, ...
Monitoring of extracellular brain glutamate concentrations by intracerebral biosensors is a promising approach to further investigate the role of this important neurotransmitter. However, amperometric biosensors are typically hampered by Faradaic interference caused by the presence of other electroactive species in the brain, such as ascorbic acid, dopamine, and uric acid. Various permselective membranes are often used on biosensors to prevent this. In this study we evaluated the most commonly used membranes, i.e. nafion, polyphenylenediamine, polypyrrole, polyaniline, and polynaphthol using a novel silica-based platinum electrodeFirst we selected the membranes with the highest sensitivity for hydrogen peroxidein vitroand an optimal selectivity against electrochemical interferents. Then we evaluated the performances of these membranes in a short lasting (3-4 hrs)in vivoexperiment. We found that bestin vitroperformance was accomplished with biosensors that were protected by a poly(m-phenylenediamine) membrane deposited onto the platinum electrode by cyclic voltammetry. However, post-implantation evaluation of these membranes showed poor selectivity against dopamine. Combination with a previously applied nafion layer did not protect the sensors against acute biofouling; indeed it was even counter effective.Finally, we investigated the ability of our biosensors to monitor the effect of glutamate transport blocker DL-TBOA on modulating glutamate concentrations in the prefrontal cortex of anaesthetized rats. The optimized biosensors recorded a rapid 35-fold increase in extracellular glutamate, and are considered suitable for further explorationin vivo
Source: Biosensors and Bioelectronics, Available online 24 January 2012
N.Wahono, S. Qin, P. Oomen, T.I.F. Cremers, M.G. de Vries, ...
Monitoring of extracellular brain glutamate concentrations by intracerebral biosensors is a promising approach to further investigate the role of this important neurotransmitter. However, amperometric biosensors are typically hampered by Faradaic interference caused by the presence of other electroactive species in the brain, such as ascorbic acid, dopamine, and uric acid. Various permselective membranes are often used on biosensors to prevent this. In this study we evaluated the most commonly used membranes, i.e. nafion, polyphenylenediamine, polypyrrole, polyaniline, and polynaphthol using a novel silica-based platinum electrodeFirst we selected the membranes with the highest sensitivity for hydrogen peroxidein vitroand an optimal selectivity against electrochemical interferents. Then we evaluated the performances of these membranes in a short lasting (3-4 hrs)in vivoexperiment. We found that bestin vitroperformance was accomplished with biosensors that were protected by a poly(m-phenylenediamine) membrane deposited onto the platinum electrode by cyclic voltammetry. However, post-implantation evaluation of these membranes showed poor selectivity against dopamine. Combination with a previously applied nafion layer did not protect the sensors against acute biofouling; indeed it was even counter effective.Finally, we investigated the ability of our biosensors to monitor the effect of glutamate transport blocker DL-TBOA on modulating glutamate concentrations in the prefrontal cortex of anaesthetized rats. The optimized biosensors recorded a rapid 35-fold increase in extracellular glutamate, and are considered suitable for further explorationin vivo
Highlights
► Several permselective membranes were studied to improve glutamate sensorsin vivoperformance ► Poly(m-PD) CV shows highest performance to repel interfering compounds ► There is no significance biofouling effect after implantation on GluOx activity ► This sensor type has the potential to be used to monitor glutamate in brainSimultaneous determination of ascorbic acid, dopamine and uric acid using high-performance screen-printed graphene electrode
23 January 2012, 22:13:51
Publication year: 2012
Source: Biosensors and Bioelectronics, Available online 21 January 2012
Jianfeng Ping, Jian Wu, Yixian Wang, Yibin Ying
A disposable and sensitive screen-printed electrode using an ink containing graphene was developed. This electrode combined the advantages of graphene and the disposable characteristic of electrode, which possessed wide potential window, low background current and fast electron transfer kinetics. Compared with the electrodes made from other inks, screen-printed graphene electrode (SPGNE) showed excellent electrocatalytic activity for the oxidation of ascorbic acid (AA), dopamine (DA), and uric acid (UA). Three well-defined sharp and fully resolved anodic peaks were found at the developed electrode. Differential pulse voltammetry was used to simultaneous determination of AA, DA, and UA in their ternary mixture. In the co-existence system of these three species, the linear response ranges for the determination of AA, DA, and UA were 4.0 − 4500 μM, 0.5 − 2000 μM, and 0.8 − 2500 μM, respectively. The detection limits (S/N = 3) were found to be 0.95 μM, 0.12 μM, and 0.20 μM for the determination of AA, DA, and UA, respectively. Furthermore, the SPGNE displayed high reproducibility and stability for these species determination. The feasibility of the developed electrode for real sample analysis was investigated. Results showed that the SPGNE could be used as a sensitive and selective sensor for simultaneous determination of AA, DA, and UA in biological samples, which may provide a promising alternative in routine sensing applications
Source: Biosensors and Bioelectronics, Available online 21 January 2012
Jianfeng Ping, Jian Wu, Yixian Wang, Yibin Ying
A disposable and sensitive screen-printed electrode using an ink containing graphene was developed. This electrode combined the advantages of graphene and the disposable characteristic of electrode, which possessed wide potential window, low background current and fast electron transfer kinetics. Compared with the electrodes made from other inks, screen-printed graphene electrode (SPGNE) showed excellent electrocatalytic activity for the oxidation of ascorbic acid (AA), dopamine (DA), and uric acid (UA). Three well-defined sharp and fully resolved anodic peaks were found at the developed electrode. Differential pulse voltammetry was used to simultaneous determination of AA, DA, and UA in their ternary mixture. In the co-existence system of these three species, the linear response ranges for the determination of AA, DA, and UA were 4.0 − 4500 μM, 0.5 − 2000 μM, and 0.8 − 2500 μM, respectively. The detection limits (S/N = 3) were found to be 0.95 μM, 0.12 μM, and 0.20 μM for the determination of AA, DA, and UA, respectively. Furthermore, the SPGNE displayed high reproducibility and stability for these species determination. The feasibility of the developed electrode for real sample analysis was investigated. Results showed that the SPGNE could be used as a sensitive and selective sensor for simultaneous determination of AA, DA, and UA in biological samples, which may provide a promising alternative in routine sensing applications
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