Advances in Optical Biosensors and Chemical Sensors

A special issue of Biosensors (ISSN 2079-6374). This special issue belongs to the section "Optical and Photonic Biosensors".

Deadline for manuscript submissions: closed (31 January 2024) | Viewed by 12630

Special Issue Editors

Department of Engineering, University of Naples “Parthenope”, 80143 Naples, Italy
Interests: chemical sensors; biosensors; physical sensors; fiber-optic sensors; fiber gratings; long period gratings; fiber Bragg gratings; fabrication of long period gratings (LPG) in specialty optical fibers; investigation of fiber optic sensors under different ionizing radiations; development of fiber optic bio-chemical sensors for industrial and medical applications
Special Issues, Collections and Topics in MDPI journals
Department of Engineering, University of Naples “Parthenope”, 80143 Naples, Italy
Interests: fiber-optic sensors; fiber bragg-grating-based sensors; long period grating sensors; biomedical sensors; photonic bandgap sensors; plasmonic sensors; optoelectronic sensors
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Biosensors are analytical devices incorporating a biological sensing element (antigen/antibody, enzyme, nucleic acid, hormone receptor, live cell, tissue, etc.) and that are capable of detecting biomolecules in a complex sample by converting the physical/chemical signal to an optical signal, which can be further associated with the concentration of the target analyte. Optical biosensors exhibit high performance in detecting biological systems and promote significant advances in clinical diagnostics, drug discovery, food process control and environmental monitoring thanks to their several advantages, such as high sensitivity, robustness, reliability, and chip integration.

This Special Issue will focus on the latest developments and trends in optical biosensors and chemical sensors, covering recent improvements in the related theory, design, fabrication, and application/validation. We warmly invite you to participate by submitting original research papers, communications, and review articles in order to provide useful insights into the present status and future outlook in this area.

Dr. Flavio Esposito
Prof. Dr. Stefania Campopiano
Prof. Dr. Agostino Iadicicco
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. Biosensors is an international peer-reviewed open access monthly 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 2700 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

  • fiber optic biosensors and chemical sensors
  • surface plasmon resonance (SPR)-based biosensors and chemical sensors
  • Raman spectroscopy
  • surface enhanced Raman spectroscopy (SERS)
  • refractive index sensors
  • fluorescence
  • luminescence
  • absorption
  • transducers for biosensors and chemical sensors
  • nanomaterials for biosensors and chemical sensors
  • surface functionalization procedures
  • lab on chip
  • microfluidics
  • point of care (POC)

Published Papers (7 papers)

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

Research

Jump to: Review

17 pages, 7062 KiB  
Article
Surface-Enhanced Spatially Offset Raman Spectroscopy in Tissue
by Dayle Kotturi, Sureyya Paterson and Mike McShane
Biosensors 2024, 14(2), 81; https://doi.org/10.3390/bios14020081 - 02 Feb 2024
Viewed by 944
Abstract
One aim of personalized medicine is to use continuous or on-demand monitoring of metabolites to adjust prescription dosages in real time. Surface-enhanced spatially offset Raman spectroscopy (SESORS) is an optical technique capable of detecting surface-enhanced Raman spectroscopy (SERS)-active targets under a barrier, which [...] Read more.
One aim of personalized medicine is to use continuous or on-demand monitoring of metabolites to adjust prescription dosages in real time. Surface-enhanced spatially offset Raman spectroscopy (SESORS) is an optical technique capable of detecting surface-enhanced Raman spectroscopy (SERS)-active targets under a barrier, which may enable frequent metabolite monitoring. Here we investigate how the intensity of the signal from SERS-active material varies spatially through tissue, both experimentally and in a computational model. Implant-sized, SERS-active hydrogel was placed under different thicknesses of contiguous tissue. Emission spectra were collected at the air-tissue boundary over a range of offsets from the excitation site. New features were added to the Monte Carlo light-tissue interaction model to modify the optical properties after inelastic scattering and to calculate the distribution of photons as they exit the model. The Raman signals were detectable through all barrier thicknesses, with strongest emission for the case of 0 mm offset between the excitation and detector. A steep decline in the signal intensities occurred for offsets greater than 2 mm. These results did not match published SORS work (where targets were much larger than an implant). However, the model and experimental results agree in showing the greatest intensities at 0 mm offset and a steep gradient in the intensities with increasing offset. Also, the model showed an increase in the number of photons when the new, longer wavelengths were used following the Stokes shift for scattering and the graphical display of the exiting photons was helpful in the determination and confirmation of the optimal offset. Full article
(This article belongs to the Special Issue Advances in Optical Biosensors and Chemical Sensors)
Show Figures

Figure 1

15 pages, 4368 KiB  
Article
A Polarity-Sensitive Far-Red Fluorescent Probe for Glucose Sensing through Skin
by Lydia Colvin, Dandan Tu, Darin Dunlap, Alberto Rios and Gerard Coté
Biosensors 2023, 13(8), 788; https://doi.org/10.3390/bios13080788 - 04 Aug 2023
Cited by 1 | Viewed by 1577
Abstract
The field of glucose biosensors for diabetes management has been of great interest over the past 60 years. Continuous glucose monitoring (CGM) is important to continuously track the glucose level to provide better management of the disease. Concanavalin A (ConA) can reversibly bind [...] Read more.
The field of glucose biosensors for diabetes management has been of great interest over the past 60 years. Continuous glucose monitoring (CGM) is important to continuously track the glucose level to provide better management of the disease. Concanavalin A (ConA) can reversibly bind to glucose and mannose molecules and form a glucose biosensor via competitive binding. Here, we developed a glucose biosensor using ConA and a fluorescent probe, which generated a fluorescent intensity change based on solvatochromism, the reversible change in the emission spectrum dependent on the polarity of the solvent. The direction in which the wavelength shifts as the solvent polarity increases can be defined as positive (red-shift), negative (blue-shift), or a combination of the two, referred to as reverse. To translate this biosensor to a subcutaneously implanted format, Cyanine 5.5 (Cy5.5)-labeled small mannose molecules were used, which allows for the far-red excitation wavelength range to increase the skin penetration depth of the light source and returned emission. Three Cy5.5-labeled small mannose molecules were synthesized and compared when used as the competing ligand in the competitive binding biosensor. We explored the polarity-sensitive nature of the competing ligands and examined the biosensor’s glucose response. Cy5.5-mannotetraose performed best as a biosensor, allowing for the detection of glucose from 25 to 400 mg/dL. Thus, this assay is responsive to glucose within the physiologic range when its concentration is increased to levels needed for an implantable design. The biosensor response is not statistically different when placed under different skin pigmentations when comparing the percent increase in fluorescence intensity. This shows the ability of the biosensor to produce a repeatable signal across the physiologic range for subcutaneous glucose monitoring under various skin tones. Full article
(This article belongs to the Special Issue Advances in Optical Biosensors and Chemical Sensors)
Show Figures

Figure 1

10 pages, 2548 KiB  
Communication
Coumarin-Based Fluorescence Probe for Differentiated Detection of Biothiols and Its Bioimaging in Cells
by Wei Du, Xiu-Lin Gong, Yang Tian, Xi Zhu, Yu Peng and Ya-Wen Wang
Biosensors 2023, 13(4), 447; https://doi.org/10.3390/bios13040447 - 31 Mar 2023
Cited by 3 | Viewed by 1390
Abstract
In this work, a coumarin derivative, SWJT-14, was synthesized as a fluorescence probe to distinguish cysteine (Cys), homocysteine (Hcy) and glutathione (GSH) in aqueous solutions. The detection limit of Cys, Hcy and GSH for the probe was 0.02 μM, 0.42 μM and [...] Read more.
In this work, a coumarin derivative, SWJT-14, was synthesized as a fluorescence probe to distinguish cysteine (Cys), homocysteine (Hcy) and glutathione (GSH) in aqueous solutions. The detection limit of Cys, Hcy and GSH for the probe was 0.02 μM, 0.42 μM and 0.92 μM, respectively, which was lower than biothiols in cells. The probe reacted with biothiols to generate different products with different conjugated structures. Additionally, it could distinguish Cys, Hcy and GSH using fluorescence and UV-Vis spectra. The detection mechanism was confirmed by MS. SWJT-14 was successfully used in cellular experiments and detected both endogenous and exogenous biothiols. Full article
(This article belongs to the Special Issue Advances in Optical Biosensors and Chemical Sensors)
Show Figures

Figure 1

18 pages, 4383 KiB  
Article
Non-Destructive and Non-Invasive Measurement of Ethanol and Toxic Alcohol Strengths in Beverages and Spirits Using Portable Raman Spectroscopy
by Panagiota Papaspyridakou, Panagiota Giannoutsou and Malvina G. Orkoula
Biosensors 2023, 13(1), 135; https://doi.org/10.3390/bios13010135 - 13 Jan 2023
Cited by 3 | Viewed by 2330
Abstract
The measurement of ethanol and toxic alcohol (methanol and isopropanol) strengths in beverages and spirits is crucial for health reasons but also for the identification of adulterated products. Many methodologies have been reported in the literature, based mainly on chromatographic and on spectroscopic [...] Read more.
The measurement of ethanol and toxic alcohol (methanol and isopropanol) strengths in beverages and spirits is crucial for health reasons but also for the identification of adulterated products. Many methodologies have been reported in the literature, based mainly on chromatographic and on spectroscopic techniques. Chromatographic techniques are laborious and time-consuming, while spectroscopic techniques are rapid and need no special sample pretreatment. All techniques were only applied to off-line or at-line manner. In the present work, Raman spectroscopy was used for fast and non-destructive measurements. A “through the container” method was developed for a non-invasive analysis, i.e., analysis without unsealing the bottles. This method, coupled with a miniature portable Raman, can serve for in-line measurements in a production line. The optimum laser focus for maximum spirit signal and minimum glass-wall signal was investigated. Calibration curves for the alcohols of interest were constructed and validated. The limits of detections were calculated and proved to be lower than the legitimate values. The influences of the liquor color and the bottle color, shape, and thickness were checked. Twenty-eight alcoholic products were studied. The concentrations found were compared against the nominal values (from the bottle labels). Full article
(This article belongs to the Special Issue Advances in Optical Biosensors and Chemical Sensors)
Show Figures

Figure 1

16 pages, 10116 KiB  
Article
A Reversible Optical Sensor Film for Mercury Ions Discrimination Based on Isoxazolidine Derivative and Exhibiting pH Sensing
by Reham Ali, Siwar Ghannay, Sabri Messaoudi, Fahad M. Alminderej, Kaïss Aouadi and Sayed M. Saleh
Biosensors 2022, 12(11), 1028; https://doi.org/10.3390/bios12111028 - 16 Nov 2022
Cited by 4 | Viewed by 1466
Abstract
We developed a new optical sensor for tracing Hg(II) ions. The detection affinity examines within a concentration range of 0–4.0 µM Hg(II). The sensor film is based on Methyl 2-hydroxy-3-(((2S,2’R,3a’S,5R)-2-isopropyl-5,5’-dimethyl-4’-oxotetrahydro-2’H-spiro[cy-clohexane-1,6’-im-idazo[1,5-b]isoxazol]-2’-yl)methyl)-5-methylbenzoate (IXZD). The novel synthesized compound could be utilized as an optical turn-on chemosensor [...] Read more.
We developed a new optical sensor for tracing Hg(II) ions. The detection affinity examines within a concentration range of 0–4.0 µM Hg(II). The sensor film is based on Methyl 2-hydroxy-3-(((2S,2’R,3a’S,5R)-2-isopropyl-5,5’-dimethyl-4’-oxotetrahydro-2’H-spiro[cy-clohexane-1,6’-im-idazo[1,5-b]isoxazol]-2’-yl)methyl)-5-methylbenzoate (IXZD). The novel synthesized compound could be utilized as an optical turn-on chemosensor for pH. The emission intensity is highly enhanced for the deprotonated form concerning the protonated form. IXZD probe has a characteristic fluorescence peak at 481 nm under excitation of 351 nm with large Stocks shift of approximately 130 nm. In addition, the binding process of IXZD:Hg(II) presents a 1:1 molar ratio which is proved by the large quench of the 481 nm emission peak of IXZD and the growth of a new emission peak at 399 nm (blue shift). The binding configurations with one Hg(II) cation and its electronic characteristics were investigated by applying the Density Functional Theory (DFT) and the time-dependent DFT (TDDFT) calculations. Density functional theory (DFT) and the time-dependent DFT (TDDFT) theoretical results were provided to examine Hg(II)-IXZD structures and their electronic properties in solution. The developed chemical sensor was offered based on the intramolecular charge transfer (ICT) mechanism. The sensor film has a significantly low limit of detection (LOD) for Hg(II) of 0.025 μM in pH 7.4, with a relative standard deviation RSDr (1%, n = 3). Lastly, the IXZD shows effective binding affinity to mercury ions, and the binding constant Kb was estimated to be 5.80 × 105 M−1. Hence, this developed optical sensor film has a significant efficiency for tracing mercury ions based on IXZD molecule-doped sensor film. Full article
(This article belongs to the Special Issue Advances in Optical Biosensors and Chemical Sensors)
Show Figures

Figure 1

14 pages, 7090 KiB  
Article
Dual Optical Nanosensor Based on Ormosil Nanoparticles for Monitoring O2 and pH
by Reham Ali
Biosensors 2022, 12(11), 1011; https://doi.org/10.3390/bios12111011 - 12 Nov 2022
Cited by 2 | Viewed by 1501
Abstract
Monitoring O2 and pH has excellent potential in different sensing applications, especially in biological and clinical applications. This report presents a protocol for synthesizing an optical dual nanosensor for those two parameters. The organically modified silica (ormosil) nanoparticles were prepared based on [...] Read more.
Monitoring O2 and pH has excellent potential in different sensing applications, especially in biological and clinical applications. This report presents a protocol for synthesizing an optical dual nanosensor for those two parameters. The organically modified silica (ormosil) nanoparticles were prepared based on phenytrimethoxysilane in an aqueous solution using an acid-base one-pot strategy. Ormosil was selected as a lipophilic matrix for loading fluorescent O2-sensitive dye platinum(II)-tetrakis-(pentafluorophenyl) porphyrin (Pt-TPFPP), which was quenched in the presence of O2 gas and exhibited a considerable detection proficiency within a percentage range of (0–100%) O2. Commercially available drug ingredient salicylamide was labeled on the surface of the nanoparticles using a coupling agent (3-glycidoxypropyl) trimethoxysilane (GPTMS). For measuring pH, salicylamide acted for the first time as a pH-sensitive probe based on a turn-on process with increasing pH. The nanosensor displayed a significant pH detection efficiency in the range of (pH = 6–10). Salicylamide turn-on fluorescence was attributed to the excited state intramolecular transfer (ESIPT) process followed by the inter charge transfer (ICT). The presented dual nanosensor opens new opportunities as a promising candidate material for industrial systems and medical applications. Full article
(This article belongs to the Special Issue Advances in Optical Biosensors and Chemical Sensors)
Show Figures

Graphical abstract

Review

Jump to: Research

37 pages, 11105 KiB  
Review
Advances in Tapered Optical Fiber Sensor Structures: From Conventional to Novel and Emerging
by Wen Zhang, Xianzheng Lang, Xuecheng Liu, Guoru Li, Ragini Singh, Bingyuan Zhang and Santosh Kumar
Biosensors 2023, 13(6), 644; https://doi.org/10.3390/bios13060644 - 12 Jun 2023
Cited by 6 | Viewed by 2423
Abstract
Optical fiber sensors based on tapered optical fiber (TOF) structure have attracted a considerable amount of attention from researchers due to the advantages of simple fabrication, high stability, and diverse structures, and have great potential for applications in many fields such as physics, [...] Read more.
Optical fiber sensors based on tapered optical fiber (TOF) structure have attracted a considerable amount of attention from researchers due to the advantages of simple fabrication, high stability, and diverse structures, and have great potential for applications in many fields such as physics, chemistry, and biology. Compared with conventional optical fibers, TOF with their unique structural characteristics significantly improves the sensitivity and response speed of fiber-optic sensors and broadens the application range. This review presents an overview of the latest research status and characteristics of fiber-optic sensors and TOF sensors. Then, the working principle of TOF sensors, fabrication schemes of TOF structures, novel TOF structures in recent years, and the growing emerging application areas are described. Finally, the development trends and challenges of TOF sensors are prospected. The objective of this review is to convey novel perspectives and strategies for the performance optimization and design of TOF sensors based on fiber-optic sensing technologies. Full article
(This article belongs to the Special Issue Advances in Optical Biosensors and Chemical Sensors)
Show Figures

Figure 1

Back to TopTop