Next Issue
Previous Issue

Table of Contents

Chemosensors, Volume 5, Issue 4 (December 2017)

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
View options order results:
result details:
Displaying articles 1-10
Export citation of selected articles as:

Editorial

Jump to: Research, Review

Open AccessEditorial Novel 2D-Inorganic Materials for Gas Sensing
Chemosensors 2017, 5(4), 29; doi:10.3390/chemosensors5040029
Received: 12 October 2017 / Revised: 12 October 2017 / Accepted: 12 October 2017 / Published: 15 October 2017
PDF Full-text (151 KB) | HTML Full-text | XML Full-text
Abstract
Nowadays, modern technology is demanding more efficient gas sensors for advanced applications [1].[...] Full article
(This article belongs to the Special Issue Novel 2D-Inorganic Materials for Gas Sensing)

Research

Jump to: Editorial, Review

Open AccessFeature PaperArticle Oxygen Sensing by the Hybrid Langmuir-Blodgett Films of Iridium(III) Complexes and Synthetic Saponite on the Basis of Energy Transfer
Chemosensors 2017, 5(4), 27; doi:10.3390/chemosensors5040027
Received: 12 August 2017 / Revised: 22 September 2017 / Accepted: 28 September 2017 / Published: 30 September 2017
PDF Full-text (3081 KB) | HTML Full-text | XML Full-text
Abstract
An ultra-thin hybrid film of amphiphilic iridium(III) complexes and synthetic saponite was manipulated by means of the modified Langmuir-Blodgett method. In the film deposited onto a quartz substrate, the external mixed molecular layer of amphiphilic iridium(III) complexes was reinforced by the inner layer
[...] Read more.
An ultra-thin hybrid film of amphiphilic iridium(III) complexes and synthetic saponite was manipulated by means of the modified Langmuir-Blodgett method. In the film deposited onto a quartz substrate, the external mixed molecular layer of amphiphilic iridium(III) complexes was reinforced by the inner layer of exfoliated synthetic saponite. As components of the molecular layer, two iridium(III) complexes were used: [Ir(dfppy)2(dc9bpy)]+ (dfppyH = 2-(4′,6′-difluorophenyl) pyridine; dc9bpy = 4,4′-dinonyl-2,2′-bipyridine) (denoted as DFPPY) and [Ir(piq)2(dc9bpy)]+ (piqH = 1-phenyisoquinoline)) denoted as PIQ). The emission spectra from the films changed from blue to red maxima with the decrease of a ratio of DFPPY/PIQ due to the energy transfer from excited DFPPY to PIQ. The intensity of red decreased with the increase of oxygen pressure through the quenching of excited iridium(III) complexes, promising a possibility as an oxygen-sensing film. Full article
Figures

Figure 1

Open AccessFeature PaperArticle Challenges in Developing a Biochip for Intact Histamine Using Commercial Antibodies
Chemosensors 2017, 5(4), 33; doi:10.3390/chemosensors5040033
Received: 16 October 2017 / Revised: 20 November 2017 / Accepted: 1 December 2017 / Published: 5 December 2017
PDF Full-text (1594 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
This study describes the development and the challenges in the development of an on-chip immunoassay for histamine using commercially available antibodies. Histamine can be used as an indicator of food freshness and quality, but it is also a relevant marker in clinical diagnostics.
[...] Read more.
This study describes the development and the challenges in the development of an on-chip immunoassay for histamine using commercially available antibodies. Histamine can be used as an indicator of food freshness and quality, but it is also a relevant marker in clinical diagnostics. Due to its low molecular weight, simple structure and thus low immunogenicity production of high specificity and affinity antibodies is difficult. From six commercial anti-histamine antibodies tested, only two bound the histamine free in the solution. A fluorescent on-chip immunoassay for histamine was established with a dynamic range of 8–111 µg/mL using polyclonal anti-histamine antibody H7403 from Sigma (Mendota Heights, MN, USA). The anti-histamine antibodies described and used in published literature are thoroughly reviewed and the quality of commercial antibodies and their traceability and quality issues are highlighted and extensively discussed. Full article
Figures

Figure 1

Open AccessFeature PaperArticle Towards Rational Chemosensor Design through Improved Understanding of Experimental Parameter Variation and Tolerance in Cyclodextrin-Promoted Fluorescence Detection
Chemosensors 2017, 5(4), 34; doi:10.3390/chemosensors5040034
Received: 18 October 2017 / Revised: 1 December 2017 / Accepted: 7 December 2017 / Published: 12 December 2017
PDF Full-text (3232 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
We have previously developed a highly efficient fluorescence-based toxicant-detection method that operates in complex environments to detect aromatic toxicants and toxicant metabolites with high sensitivity and selectivity. This method relies on the ability of γ-cyclodextrin to act as a supramolecular scaffold, and uses
[...] Read more.
We have previously developed a highly efficient fluorescence-based toxicant-detection method that operates in complex environments to detect aromatic toxicants and toxicant metabolites with high sensitivity and selectivity. This method relies on the ability of γ-cyclodextrin to act as a supramolecular scaffold, and uses a variety of non-covalent interactions between the cyclodextrin, toxicant, and fluorophore to enable efficient detection. Reported herein is an investigation of the effect of various experimental parameters, including host concentration, temperature, pH, salt, and solvent, on the observed energy-transfer efficiencies. These results advance our understanding of γ-cyclodextrin-based association complexes and provide crucial information for the development of fluorescence-based sensors using such complexation and the resultant fluorescence-based detection. Full article
(This article belongs to the Special Issue Label-Free Biosensors and Chemical Sensors)
Figures

Open AccessFeature PaperArticle Biochars as Innovative Humidity Sensing Materials
Chemosensors 2017, 5(4), 35; doi:10.3390/chemosensors5040035
Received: 30 October 2017 / Revised: 6 December 2017 / Accepted: 11 December 2017 / Published: 12 December 2017
PDF Full-text (5501 KB) | HTML Full-text | XML Full-text
Abstract
In this work, biochar-based humidity sensors were prepared by drop-coating technique. Polyvinylpyrrolidone (PVP) was added as an organic binder to improve the adhesion of the sensing material onto ceramic substrates having platinum electrodes. Two biochars obtained from different precursors were used. The sensors
[...] Read more.
In this work, biochar-based humidity sensors were prepared by drop-coating technique. Polyvinylpyrrolidone (PVP) was added as an organic binder to improve the adhesion of the sensing material onto ceramic substrates having platinum electrodes. Two biochars obtained from different precursors were used. The sensors were tested toward relative humidity (RH) at room temperature and showed a response starting around 5 RH%, varying the impedance of 2 orders of magnitude after exposure to almost 100% relative humidity. In both cases, biochar materials are behaving as p-type semiconductors under low amounts of humidity. On the contrary, for higher RH values, the impedance decreased due to water molecules adsorption. When PVP is added to SWP700 biochar, n-p heterojunctions are formed between the two semiconductors, leading to a higher sensitivity at low RH values for the sensors SWP700-10% PVP and SWP700-20% PVP with respect to pure SWP700 sensor. Finally, response and recovery times were both reasonably fast (in the order of 1 min). Full article
(This article belongs to the Special Issue Polymers Based Chemical Sensors)
Figures

Figure 1

Review

Jump to: Editorial, Research

Open AccessFeature PaperReview Possibilities and Challenges for Quantitative Optical Sensing of Hydrogen Peroxide
Chemosensors 2017, 5(4), 28; doi:10.3390/chemosensors5040028
Received: 11 September 2017 / Revised: 3 October 2017 / Accepted: 5 October 2017 / Published: 11 October 2017
PDF Full-text (2161 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Hydrogen peroxide (H2O2) plays a key role in many biological processes spanning from coral bleaching, over cell signaling to aging. However, exact quantitative assessments of concentrations and dynamics of H2O2 remain challenging due to methodological limitations—especially
[...] Read more.
Hydrogen peroxide (H2O2) plays a key role in many biological processes spanning from coral bleaching, over cell signaling to aging. However, exact quantitative assessments of concentrations and dynamics of H2O2 remain challenging due to methodological limitations—especially at very low (sub μM) concentrations. Most published optical detection schemes for H2O2 suffer from irreversibility, cross sensitivity to other analytes such as other reactive oxygen species (ROS) or pH, instability, temperature dependency or limitation to a specific medium. We review optical detection schemes for H2O2, compare their specific advantages and disadvantages, and discuss current challenges and new approaches for quantitative optical H2O2 detection, with a special focus on luminescence-based measurements. We also review published concentration ranges for H2O2 in natural habitats, and physiological concentrations in different biological samples to provide guidelines for future experiments and sensor development in biomedical and environmental science. Full article
Figures

Figure 1

Open AccessReview Microdevices for Non-Invasive Detection of Bladder Cancer
Chemosensors 2017, 5(4), 30; doi:10.3390/chemosensors5040030
Received: 27 September 2017 / Revised: 7 November 2017 / Accepted: 15 November 2017 / Published: 19 November 2017
PDF Full-text (2217 KB) | HTML Full-text | XML Full-text
Abstract
Bladder cancer holds the record for the highest lifetime cost on a per-patient basis. This is due to high recurrence rates, which necessitate invasive and costly long-term evaluation methods such as cystoscopy and imaging. Microfluidics is emerging as an important approach to contribute
[...] Read more.
Bladder cancer holds the record for the highest lifetime cost on a per-patient basis. This is due to high recurrence rates, which necessitate invasive and costly long-term evaluation methods such as cystoscopy and imaging. Microfluidics is emerging as an important approach to contribute to initial diagnosis and follow-up, by enabling the precise manipulation of biological samples. Specifically, microdevices have been used for the isolation of cells or genetic material from blood samples, sparking significant interest as a versatile platform for non-invasive bladder cancer detection with voided urine. In this review, we revisit the methods of bladder cancer detection and describe various types of markers currently used for evaluation. We detail cutting-edge technologies and evaluate their merits in the detection, screening, and diagnosis of bladder cancer. Advantages of microscale devices over standard methods of detection, as well as their limitations, are provided. We conclude with a discussion of criteria for guiding microdevice development that could deepen our understanding of prognoses at the level of individual patients and the underlying biology of bladder cancer development. Collectively, the development and widespread application of improved microfluidic devices for bladder cancer could drive treatment breakthroughs and establish widespread, tangible outcomes on patients’ long-term survival. Full article
Figures

Figure 1

Open AccessReview Polymeric Materials for Printed-Based Electroanalytical (Bio)Applications
Chemosensors 2017, 5(4), 31; doi:10.3390/chemosensors5040031
Received: 23 October 2017 / Revised: 21 November 2017 / Accepted: 22 November 2017 / Published: 24 November 2017
PDF Full-text (2149 KB) | HTML Full-text | XML Full-text
Abstract
Advances in design of selective interfaces and printed technology have mighty contributed to the expansion of the electroanalysis fame. The real advantage in electroanalytical field is the possibility to manufacture and customize plenty of different sensing platforms, thus avoiding expensive equipment, hiring skilled
[...] Read more.
Advances in design of selective interfaces and printed technology have mighty contributed to the expansion of the electroanalysis fame. The real advantage in electroanalytical field is the possibility to manufacture and customize plenty of different sensing platforms, thus avoiding expensive equipment, hiring skilled personnel, and expending economic effort. Growing developments in polymer science have led to further improvements in electroanalytical methods such as sensitivity, selectivity, reproducibility, and accuracy. This review provides an overview of the technical procedures that are used in order to establish polymer effectiveness in printed-based electroanalytical methods. Particular emphasis is placed on the development of electronalytical sensors and biosensors, which highlights the diverse role of the polymeric materials depending on their specific application. A wide overview is provided, taking into account the most significant findings that have been reported from 2010 to 2017. Full article
(This article belongs to the Special Issue Polymers Based Chemical Sensors)
Figures

Figure 1

Open AccessReview Illuminating Brain Activities with Fluorescent Protein-Based Biosensors
Chemosensors 2017, 5(4), 32; doi:10.3390/chemosensors5040032
Received: 9 October 2017 / Revised: 19 November 2017 / Accepted: 22 November 2017 / Published: 28 November 2017
PDF Full-text (2373 KB) | HTML Full-text | XML Full-text
Abstract
Fluorescent protein-based biosensors are indispensable molecular tools for life science research. The invention and development of high-fidelity biosensors for a particular molecule or molecular event often catalyze important scientific breakthroughs. Understanding the structural and functional organization of brain activities remain a subject for
[...] Read more.
Fluorescent protein-based biosensors are indispensable molecular tools for life science research. The invention and development of high-fidelity biosensors for a particular molecule or molecular event often catalyze important scientific breakthroughs. Understanding the structural and functional organization of brain activities remain a subject for which optical sensors are in desperate need and of growing interest. Here, we review genetically encoded fluorescent sensors for imaging neuronal activities with a focus on the design principles and optimizations of various sensors. New bioluminescent sensors useful for deep-tissue imaging are also discussed. By highlighting the protein engineering efforts and experimental applications of these sensors, we can consequently analyze factors influencing their performance. Finally, we remark on how future developments can fill technological gaps and lead to new discoveries. Full article
(This article belongs to the Special Issue Fluorescent Probes for Live Cell Imaging)
Figures

Figure 1

Open AccessFeature PaperReview Luminescent Metal Nanoclusters for Potential Chemosensor Applications
Chemosensors 2017, 5(4), 36; doi:10.3390/chemosensors5040036
Received: 21 November 2017 / Revised: 7 December 2017 / Accepted: 8 December 2017 / Published: 19 December 2017
PDF Full-text (5893 KB) | HTML Full-text | XML Full-text
Abstract
Studies of metal nanocluster (M-NCs)-based sensors for specific analyte detection have achieved significant progress in recent decades. Ultra-small-size (<2 nm) M-NCs consist of several to a few hundred metal atoms and exhibit extraordinary physical and chemical properties. Similar to organic molecules, M-NCs display
[...] Read more.
Studies of metal nanocluster (M-NCs)-based sensors for specific analyte detection have achieved significant progress in recent decades. Ultra-small-size (<2 nm) M-NCs consist of several to a few hundred metal atoms and exhibit extraordinary physical and chemical properties. Similar to organic molecules, M-NCs display absorption and emission properties via electronic transitions between energy levels upon interaction with light. As such, researchers tend to apply M-NCs in diverse fields, such as in chemosensors, biological imaging, catalysis, and environmental and electronic devices. Chemo- and bio-sensory uses have been extensively explored with luminescent NCs of Au, Ag, Cu, and Pt as potential sensory materials. Luminescent bi-metallic NCs, such as Au-Ag, Au-Cu, Au-Pd, and Au-Pt have also been used as probes in chemosensory investigations. Both metallic and bi-metallic NCs have been utilized to detect various analytes, such as metal ions, anions, biomolecules, proteins, acidity or alkalinity of a solution (pH), and nucleic acids, at diverse detection ranges and limits. In this review, we have summarized the chemosensory applications of luminescent M-NCs and bi-metallic NCs. Full article
Figures

Figure 1

Back to Top