sensors-logo

Journal Browser

Journal Browser

Editorial Board Members' Collection Series: Fluorescent Sensors

A special issue of Sensors (ISSN 1424-8220). This special issue belongs to the section "Optical Sensors".

Deadline for manuscript submissions: closed (25 February 2024) | Viewed by 16955

Special Issue Editors

Dipartimento di Chimica e Biologia “Adolfo Zambelli”, Università degli Studi di Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy
Interests: fluorescence; sensors; hydrogen sulfide
1. Basic Medical Science, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA
2. Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
Interests: spectroscopy; point of detection modalities for pathogen detection; flow cytometry; fluorescence detection
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues, 

Fluorescence-based methods offer several advantages over other analytical procedures, such as the use of very simple and inexpensive instrumentation. Indeed, fluorescence is by far the method most often applied and the dominant analytical approach in a large variety of schemes in the fields of sensing, medical testing, biotechnology, and drug discovery. An effective fluorescence-based probe should respond in a selective manner and with high sensitivity to its target analyte. This issue deals with recent progress in the field of fluorescence-based probes for the detection of relevant analytes. In particular, our aim is to provide an overview of systems and highlight their potential in different applications across different fields of research.

Dr. Maria Strianese
Prof. Dr. J. Paul Robinson
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Sensors is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • fluorescence
  • sensors
  • sensing devices
  • optical-based applications
  • biological media

Published Papers (9 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

17 pages, 6512 KiB  
Article
Spectral Investigations of Fluorescence Tracers in Automotive and Aviation Fuels under Cryogenic Conditions
by Matthias Koegl, Jonas Vogler and Lars Zigan
Sensors 2024, 24(3), 724; https://doi.org/10.3390/s24030724 - 23 Jan 2024
Viewed by 690
Abstract
This study investigated spectral laser-induced fluorescence signals of dyes in fuels for automotive and aerospace applications under low temperatures and cryogenic conditions down to 183 K. For this purpose, a fluorescence chamber was developed based on cooling with liquid nitrogen. The design enabled [...] Read more.
This study investigated spectral laser-induced fluorescence signals of dyes in fuels for automotive and aerospace applications under low temperatures and cryogenic conditions down to 183 K. For this purpose, a fluorescence chamber was developed based on cooling with liquid nitrogen. The design enabled a minimal inner chamber temperature of 153 K. Furthermore, the applicability of two-color LIF for liquid thermometry was evaluated under these conditions. The temperature determination was based on the temperature-sensitive fluorescence intensity ratio of the special dyes doped into the fuels determined in suitable spectral regions, which represented common bandpass filters. For this purpose, the fluorescence signals of the dye doped into the gasoline and jet fuel surrogate isooctane were tested as well as blends of isooctane and the ethanol biofuels E20 (comprising 80 vol.% isooctane and 20 vol.% ethanol), E40, and E100. Additionally, a realistic multi-component fuel Jet A-1 mixed with a suitable fluorescence dye was investigated. E100 was doped with Eosin-Y, and the remaining fuels were doped with Nile red. Temperature-dependent spectral LIF intensities were recorded in the range of 183 K–293 K, which simulate extreme environments for aerospace and automotive applications. Frozen fuel–dye mixtures cause significant extinction effects and prevent sufficient signal detection at low and cryogenic temperatures, defining the detection limit. A temperature decrease led to a spectral shift in the emission peaks of E100 doped with Eosin-Y toward shorter wavelengths, while the spectra of mixtures doped with Nile red were shifted toward longer wavelengths. The suggested bandpass filters produced the temperature-sensitive intensity ratio (the average over the temperature interval) of the dyes with the largest sensitivity for Jet A-1 (5.2%/K), followed by E100 (4.95%/K), E40 (4.07%/K), E20 (3.23%/K), and isooctane (3.07%/K), even at cryogenic temperatures. Full article
(This article belongs to the Special Issue Editorial Board Members' Collection Series: Fluorescent Sensors)
Show Figures

Figure 1

11 pages, 1930 KiB  
Article
A Zinc(II) Schiff Base Complex as Fluorescent Chemosensor for the Selective and Sensitive Detection of Copper(II) in Aqueous Solution
by Ivan Pietro Oliveri, Agostino Attinà and Santo Di Bella
Sensors 2023, 23(8), 3925; https://doi.org/10.3390/s23083925 - 12 Apr 2023
Cited by 4 | Viewed by 1924
Abstract
The development of chemosensors able to detect analytes in a variety of sample matrices through a low-cost, fast, and direct approach is of current interest in food, health, industrial, and environmental fields. This contribution presents a simple approach for the selective and sensitive [...] Read more.
The development of chemosensors able to detect analytes in a variety of sample matrices through a low-cost, fast, and direct approach is of current interest in food, health, industrial, and environmental fields. This contribution presents a simple approach for the selective and sensitive detection of Cu2+ ions in aqueous solution based on a transmetalation process of a fluorescent substituted Zn(salmal) complex. Transmetalation is accompanied by relevant optical absorption changes and quenching of the fluorescence emission, leading to high selectivity and sensitivity of the chemosensor, with the advantage of not requiring any sample pretreatment or pH adjustment. Competitive experiments demonstrate a high selectivity of the chemosensor towards Cu2+ with respect to the most common metal cations as potential interferents. A limit of detection down to 0.20 μM and a dynamic linear range up to 40 μM are achieved from fluorometric data. By exploiting the fluorescence quenching upon formation of the copper(II) complex, simple paper-based sensor strips, visible to naked eyes under UV light, are used for the rapid, qualitative, and quantitative in situ detection of Cu2+ ions in aqueous solution over a wide concentration range, up to 10.0 mM, in specific environments, such as in industrial wastewater, where higher concentrations of Cu2+ ions can occur. Full article
(This article belongs to the Special Issue Editorial Board Members' Collection Series: Fluorescent Sensors)
Show Figures

Graphical abstract

13 pages, 2270 KiB  
Article
Serotonin-Derived Fluorophore: A Novel Fluorescent Biomaterial for Copper Detection in Urine
by Mariagrazia Lettieri, Simona Scarano, Laura Caponi, Andrea Bertolini, Alessandro Saba, Pasquale Palladino and Maria Minunni
Sensors 2023, 23(6), 3030; https://doi.org/10.3390/s23063030 - 10 Mar 2023
Viewed by 1102
Abstract
We took advantage of the fluorescent features of a serotonin-derived fluorophore to develop a simple and low-cost assay for copper in urine. The quenching-based fluorescence assay linearly responds within the concentration range of clinical interest in buffer and in artificial urine, showing very [...] Read more.
We took advantage of the fluorescent features of a serotonin-derived fluorophore to develop a simple and low-cost assay for copper in urine. The quenching-based fluorescence assay linearly responds within the concentration range of clinical interest in buffer and in artificial urine, showing very good reproducibility (CVav% = 4% and 3%) and low detection limits (16 ± 1 μg L−1 and 23 ± 1 μg L−1). The Cu2+ content was also estimated in human urine samples, showing excellent analytical performances (CVav% = 1%), with a limit of detection of 59 ± 3 μg L−1 and a limit of quantification of 97 ± 11 μg L−1, which are below the reference value for a pathological Cu2+ concentration. The assay was successfully validated through mass spectrometry measurements. To the best of our knowledge, this is the first example of copper ion detection exploiting the fluorescence quenching of a biopolymer, offering a potential diagnostic tool for copper-dependent diseases. Full article
(This article belongs to the Special Issue Editorial Board Members' Collection Series: Fluorescent Sensors)
Show Figures

Graphical abstract

14 pages, 4515 KiB  
Article
Sol-Gel Dipping Devices for H2S Visualization
by Maria Strianese, Giovanni Ferrara, Viktoriia Vykhovanets, Naym Blal, Daniela Guarnieri, Alessandro Landi, Marina Lamberti, Andrea Peluso and Claudio Pellecchia
Sensors 2023, 23(4), 2023; https://doi.org/10.3390/s23042023 - 10 Feb 2023
Cited by 3 | Viewed by 981
Abstract
In this contribution we report the synthesis and full characterization, via a combination of different spectroscopies (e.g., 1H NMR, UV-vis, fluorescence, MALDI), of a new family of fluorescent zinc complexes with extended π-conjugated systems, with the final aim of setting up higher [...] Read more.
In this contribution we report the synthesis and full characterization, via a combination of different spectroscopies (e.g., 1H NMR, UV-vis, fluorescence, MALDI), of a new family of fluorescent zinc complexes with extended π-conjugated systems, with the final aim of setting up higher performance H2S sensing devices. Immobilization of the systems into a polymeric matrix for use in a solid-state portable device was also explored. The results provided proof-of-principle that the title complexes could be successfully implemented in a fast, simple and cost-effective H2S sensing device. Full article
(This article belongs to the Special Issue Editorial Board Members' Collection Series: Fluorescent Sensors)
Show Figures

Figure 1

20 pages, 13292 KiB  
Article
Discriminative ‘Turn-on’ Detection of Al3+ and Ga3+ Ions as Well as Aspartic Acid by Two Fluorescent Chemosensors
by Hina Goyal, Ibrahim Annan, Deepali Ahluwalia, Arijit Bag and Rajeev Gupta
Sensors 2023, 23(4), 1798; https://doi.org/10.3390/s23041798 - 06 Feb 2023
Cited by 4 | Viewed by 2011
Abstract
In this work, two Schiff-base-based chemosensors L1 and L2 containing electron-rich quinoline and anthracene rings were designed. L1 is AIEE active in a MeOH-H2O solvent system while formed aggregates as confirmed by the DLS measurements and fluorescence lifetime studies. The chemosensor [...] Read more.
In this work, two Schiff-base-based chemosensors L1 and L2 containing electron-rich quinoline and anthracene rings were designed. L1 is AIEE active in a MeOH-H2O solvent system while formed aggregates as confirmed by the DLS measurements and fluorescence lifetime studies. The chemosensor L1 was used for the sensitive, selective, and reversible ‘turn-on’ detection of Al3+ and Ga3+ ions as well as Aspartic Acid (Asp). Chemosensor L2, an isomer of L1, was able to selectively detect Ga3+ ion even in the presence of Al3+ ions and thus was able to discriminate between the two ions. The binding mode of chemosensors with analytes was substantiated through a combination of 1H NMR spectra, mass spectra, and DFT studies. The ‘turn-on’ nature of fluorescence sensing by the two chemosensors enabled the development of colorimetric detection, filter-paper-based test strips, and polystyrene film-based detection techniques. Full article
(This article belongs to the Special Issue Editorial Board Members' Collection Series: Fluorescent Sensors)
Show Figures

Figure 1

15 pages, 4118 KiB  
Article
Exploring Coumarin-Based Boron Emissive Complexes as Temperature Thermometers in Polymer-Supported Materials
by Gonçalo Pedro, Frederico Duarte, Dmitrii A. Cheptsov, Nikita Yu. Volodin, Ivan V. Ivanov, Hugo M. Santos, Jose Luis Capelo-Martinez, Cristián Cuerva, Elisabete Oliveira, Valerii F. Traven and Carlos Lodeiro
Sensors 2023, 23(3), 1689; https://doi.org/10.3390/s23031689 - 03 Feb 2023
Cited by 3 | Viewed by 1957
Abstract
Three coumarin-based boron complexes (L1, L2 and L3) were designed and successfully incorporated into polymeric matrixes for evaluation as temperature probes. The photophysical properties of the complexes were carried out in different solvents and in the solid state. In solution, compound L1 exhibited [...] Read more.
Three coumarin-based boron complexes (L1, L2 and L3) were designed and successfully incorporated into polymeric matrixes for evaluation as temperature probes. The photophysical properties of the complexes were carried out in different solvents and in the solid state. In solution, compound L1 exhibited the highest fluorescence quantum yield, 33%, with a positive solvatochromism also being observed on the absorption and emission when the polarity of the solvent increased. Additionally in the presence of anions, L1 showed a colour change from yellow to pink, followed by a quenching in the emission intensity, which is due to deprotonation with the formation of a quinone base. Absorption and fluorescence spectra of L1 were calculated at different temperatures by the DFT/B3LYP method. The decrease in fluorescence of compound L1 with an increase in temperature seems to be due to the presence of pronounced torsional vibrations of the donor and acceptor fragments relative to the single bond with C(carbonyl)-C (styrene fragment). L1, L2 and L3, through their incorporation into the polymeric matrixes, became highly emissive by aggregation. These dye@doped polymers were evaluated as temperature sensors, showing an excellent fluorescent response and reversibility after 15 cycles of heating and cooling. Full article
(This article belongs to the Special Issue Editorial Board Members' Collection Series: Fluorescent Sensors)
Show Figures

Figure 1

17 pages, 3769 KiB  
Article
Fluorescence Detecting of Paraquat and Diquat Using Host–Guest Chemistry with a Fluorophore-Pendant Calix[6]arene
by Ermanno Vasca, Francesco Siano and Tonino Caruso
Sensors 2023, 23(3), 1120; https://doi.org/10.3390/s23031120 - 18 Jan 2023
Cited by 1 | Viewed by 1231
Abstract
Paraquat (PQ) and diquat (DQ), some of the most widely used herbicides in the world, both present a high mortality index after intentional exposure. In this paper, a fluorescence sensing method for PQ and DQ, based on host–guest molecular recognition, is proposed. Calix[6]arene [...] Read more.
Paraquat (PQ) and diquat (DQ), some of the most widely used herbicides in the world, both present a high mortality index after intentional exposure. In this paper, a fluorescence sensing method for PQ and DQ, based on host–guest molecular recognition, is proposed. Calix[6]arene derivatives containing anthracene or naphthalene as pendant fluorophore at their lower rim recognize DQ and PQ in hydroalcoholic solution with a broad linear response range at the μg L−1 level concentration. The linear response ranges were found from 1.0 to 18 μg L−1 with the detection limit of 31 ng L−1 for paraquat, and from 1.0 to 44 μg L−1 with the detection limit of 0.16 μg L−1 for diquat. The recognition process is detected by following the decrease in the fluorescence emission consequent to complexation. The proposed quenching method has been applied to the determination of paraquat in drinking water samples. Full article
(This article belongs to the Special Issue Editorial Board Members' Collection Series: Fluorescent Sensors)
Show Figures

Figure 1

Review

Jump to: Research

22 pages, 4943 KiB  
Review
Fluorescence-Based Portable Assays for Detection of Biological and Chemical Analytes
by Peuli Nath, Kazi Ridita Mahtaba and Aniruddha Ray
Sensors 2023, 23(11), 5053; https://doi.org/10.3390/s23115053 - 25 May 2023
Cited by 3 | Viewed by 3883
Abstract
Fluorescence-based detection techniques are part of an ever-expanding field and are widely used in biomedical and environmental research as a biosensing tool. These techniques have high sensitivity, selectivity, and a short response time, making them a valuable tool for developing bio-chemical assays. The [...] Read more.
Fluorescence-based detection techniques are part of an ever-expanding field and are widely used in biomedical and environmental research as a biosensing tool. These techniques have high sensitivity, selectivity, and a short response time, making them a valuable tool for developing bio-chemical assays. The endpoint of these assays is defined by changes in fluorescence signal, in terms of its intensity, lifetime, and/or shift in spectrum, which is monitored using readout devices such as microscopes, fluorometers, and cytometers. However, these devices are often bulky, expensive, and require supervision to operate, which makes them inaccessible in resource-limited settings. To address these issues, significant effort has been directed towards integrating fluorescence-based assays into miniature platforms based on papers, hydrogels, and microfluidic devices, and to couple these assays with portable readout devices like smartphones and wearable optical sensors, thereby enabling point-of-care detection of bio-chemical analytes. This review highlights some of the recently developed portable fluorescence-based assays by discussing the design of fluorescent sensor molecules, their sensing strategy, and the fabrication of point-of-care devices. Full article
(This article belongs to the Special Issue Editorial Board Members' Collection Series: Fluorescent Sensors)
Show Figures

Figure 1

25 pages, 5348 KiB  
Review
New Insights to Design Electrospun Fibers with Tunable Electrical Conductive–Semiconductive Properties
by William Serrano-Garcia, Irene Bonadies, Sylvia W. Thomas and Vincenzo Guarino
Sensors 2023, 23(3), 1606; https://doi.org/10.3390/s23031606 - 01 Feb 2023
Cited by 11 | Viewed by 2289
Abstract
Fiber electronics, such as those produced by the electrospinning technique, have an extensive range of applications including electrode surfaces for batteries and sensors, energy storage, electromagnetic interference shielding, antistatic coatings, catalysts, drug delivery, tissue engineering, and smart textiles. New composite materials and blends [...] Read more.
Fiber electronics, such as those produced by the electrospinning technique, have an extensive range of applications including electrode surfaces for batteries and sensors, energy storage, electromagnetic interference shielding, antistatic coatings, catalysts, drug delivery, tissue engineering, and smart textiles. New composite materials and blends from conductive–semiconductive polymers (C-SPs) offer high surface area-to-volume ratios with electrical tunability, making them suitable for use in fields including electronics, biofiltration, tissue engineering, biosensors, and “green polymers”. These materials and structures show great potential for embedded-electronics tissue engineering, active drug delivery, and smart biosensing due to their electronic transport behavior and mechanical flexibility with effective biocompatibility. Doping, processing methods, and morphologies can significantly impact the properties and performance of C-SPs and their composites. This review provides an overview of the current literature on the processing of C-SPs as nanomaterials and nanofibrous structures, mainly emphasizing the electroactive properties that make these structures suitable for various applications. Full article
(This article belongs to the Special Issue Editorial Board Members' Collection Series: Fluorescent Sensors)
Show Figures

Figure 1

Back to TopTop