1
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Obloy LM, Jockusch S, Tarnovsky AN. Shortwave infrared polymethine dyes for bioimaging: ultrafast relaxation dynamics and excited-state decay pathways. Phys Chem Chem Phys 2024; 26:24261-24278. [PMID: 38895857 DOI: 10.1039/d4cp01411a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Excited-state relaxation in two prototypical shortwave infrared (SWIR) polymethine dyes developed for bioimaging, heptamethine chromenylium Chrom7 and flavylium Flav7, is studied by means of femtosecond transient absorption with broadband ultraviolet-to-SWIR probing complemented by steady-state and time-resolved fluorescence and phosphorescence measurements. The relaxation processes of the dyes in dichloromethane are resolved with sub-100 fs temporal resolution using SWIR, near-IR, and visible photoexcitation. Different population members of the ground-state inhomogeneous ensemble are found to equilibrate via skeletal deformation changes with time constants of 90 fs and either 230 fs (Chrom7) and 350 fs (Flav7) followed by slower evolution matching the 1-ps timescale of diffusive solvation dynamics. Molecules excited into high-lying singlet electronic states (Sn) by visible excitation repopulate with time constants of 400 fs (Chrom7) and 450 fs (Flav7) the corresponding first excited singlet S1 states, which decay within several hundreds of picoseconds in dichloromethane and chloroform solvents. Vibrational relaxation in S1 for both Chrom7 and Flav7 in dichloromethane occurs with time constants of 350 and 800 fs for excess of vibrational energy of ∼1000 and 10 000 cm-1 deposited by near-IR and visible excitation, respectively. Two competing non-radiative processes are present in S1: temperature-independent internal conversion, and thermally-activated twisting about a carbon-carbon bond of the conjugated chain, which is substantial at room temperature but essentially nonreactive, producing traces of isomer product. Intersystem crossing in S1, and thus the triplet quantum yield, is minor. The importance of absorption bands from the excited S1 state in applications requiring high-intensity excitation conditions is discussed.
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Affiliation(s)
- Laura M Obloy
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403, USA.
| | - Steffen Jockusch
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403, USA.
| | - Alexander N Tarnovsky
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403, USA.
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2
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Porolnik W, Koczorowski T, Wieczorek-Szweda E, Szczolko W, Falkowski M, Piskorz J. Microwave-assisted synthesis, photochemical and electrochemical studies of long-wavelength BODIPY dyes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 314:124188. [PMID: 38554692 DOI: 10.1016/j.saa.2024.124188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 02/25/2024] [Accepted: 03/24/2024] [Indexed: 04/02/2024]
Abstract
Novel BODIPY derivatives possessing different styryl substituents were synthesized using different methods of Knoevenagel-type condensation with conventional heating and microwave radiation in two conditions. Microwave-assisted synthesis significantly reduces reaction time while enhancing its efficiency. The introduction of styryl substituents at the 3 and 5 positions of the BODIPY core resulted in a substantial bathochromic shift, which was affected by the substituents within styryl groups. Depending on the solvents, the BODIPY with unsubstituted styryl groups possesses absorption maxima (λAbs) between 616 and 626 nm. While the analogs containing electron-donating methoxy and methylthio groups exhibited bathochromically shifted bands with λAbs values in the 633-654 nm range. Fluorescence studies revealed intensive emission of tested BODIPYs with fluorescence quantum yields at the 0.41-0.83 range. On the other hand, singlet oxygen quantum yields were very low. In the electrochemical studies, the CV and DPV scans showed the presence of three redox processes. The calculated electrochemical gaps were in the range of 1.71-1.87 V.
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Affiliation(s)
- Weronika Porolnik
- Chair and Department of Inorganic and Analytical Chemistry, Poznan University of Medical Sciences, Rokietnicka 3, 60-806 Poznan, Poland; Doctoral School, Poznan University of Medical Sciences, Bukowska 70, 60-812 Poznan, Poland
| | - Tomasz Koczorowski
- Chair and Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Rokietnicka 3, 60-806 Poznan, Poland
| | - Ewelina Wieczorek-Szweda
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznanskiego 8, 61-614 Poznan, Poland
| | - Wojciech Szczolko
- Chair and Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Rokietnicka 3, 60-806 Poznan, Poland
| | - Michal Falkowski
- Department of Medicinal Chemistry, Collegium Medicum in Bydgoszcz, Faculty of Pharmacy, Nicolaus Copernicus University in Torun, Dr. A. Jurasza 2, 85-089 Bydgoszcz, Poland
| | - Jaroslaw Piskorz
- Chair and Department of Inorganic and Analytical Chemistry, Poznan University of Medical Sciences, Rokietnicka 3, 60-806 Poznan, Poland.
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3
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Piretta F, Samà F, Bontempi F, Elaskar J, Angeloni D, Oton CJ. Interferometer-based chemical sensor on chip with enhanced responsivity and low-cost interrogation. BIOMEDICAL OPTICS EXPRESS 2024; 15:2767-2779. [PMID: 38855700 PMCID: PMC11161349 DOI: 10.1364/boe.520195] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 02/22/2024] [Accepted: 02/22/2024] [Indexed: 06/11/2024]
Abstract
We report experimental results of an interferometric chemical sensor integrated on a silicon chip. The sensor measures refractive index variations of the liquid that contacts exposed spiraled silicon waveguides on one branch of a Mach-Zehnder interferometer. The system requires neither laser tuning nor spectral analysis, but a laser at a fixed wavelength, and a demodulation architecture that includes an internal phase modulator and a real-time processing algorithm based on multitone mixing. Two devices are compared in terms of sensitivity and noise, one at 1550 nm wavelength and TE polarization, and an optimized device at 1310 nm and TM polarization, which shows 3 times higher sensitivity and a limit of detection of 2.24·10-7 RIU.
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Affiliation(s)
- Flaminia Piretta
- Scuola Superiore Sant’Anna, Institute of Mechanical Intelligence, Via G. Moruzzi 1, 56124, Pisa, Italy
- Scuola Superiore Sant’Anna, Institute of Biorobotics, Viale Rinaldo Piaggio 34, 56025, Pontedera, Italy
| | - Francesca Samà
- Scuola Superiore Sant’Anna, Institute of Mechanical Intelligence, Via G. Moruzzi 1, 56124, Pisa, Italy
| | | | - Javier Elaskar
- Scuola Superiore Sant’Anna, Institute of Mechanical Intelligence, Via G. Moruzzi 1, 56124, Pisa, Italy
| | - Debora Angeloni
- Scuola Superiore Sant’Anna, Institute of Biorobotics, Viale Rinaldo Piaggio 34, 56025, Pontedera, Italy
| | - Claudio J. Oton
- Scuola Superiore Sant’Anna, Institute of Mechanical Intelligence, Via G. Moruzzi 1, 56124, Pisa, Italy
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4
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Lai LL, Huang PH, Stemme G, Niklaus F, Gylfason KB. 3D Printing of Glass Micro-Optics with Subwavelength Features on Optical Fiber Tips. ACS NANO 2024; 18:10788-10797. [PMID: 38551815 PMCID: PMC11044591 DOI: 10.1021/acsnano.3c11030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 03/11/2024] [Accepted: 03/14/2024] [Indexed: 04/24/2024]
Abstract
Integration of functional materials and structures on the tips of optical fibers has enabled various applications in micro-optics, such as sensing, imaging, and optical trapping. Direct laser writing is a 3D printing technology that holds promise for fabricating advanced micro-optical structures on fiber tips. To date, material selection has been limited to organic polymer-based photoresists because existing methods for 3D direct laser writing of inorganic materials involve high-temperature processing that is not compatible with optical fibers. However, organic polymers do not feature stability and transparency comparable to those of inorganic glasses. Herein, we demonstrate 3D direct laser writing of inorganic glass with a subwavelength resolution on optical fiber tips. We show two distinct printing modes that enable the printing of solid silica glass structures ("Uniform Mode") and self-organized subwavelength gratings ("Nanograting Mode"), respectively. We illustrate the utility of our approach by printing two functional devices: (1) a refractive index sensor that can measure the indices of binary mixtures of acetone and methanol at near-infrared wavelengths and (2) a compact polarization beam splitter for polarization control and beam steering in an all-in-fiber system. By combining the superior material properties of glass with the plug-and-play nature of optical fibers, this approach enables promising applications in fields such as fiber sensing, optical microelectromechanical systems (MEMS), and quantum photonics.
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Affiliation(s)
- Lee-Lun Lai
- Division
of Micro and Nanosystems, School of Electrical Engineering and Computer
Science, KTH Royal Institute of Technology, Stockholm 10044, Sweden
| | - Po-Han Huang
- Division
of Micro and Nanosystems, School of Electrical Engineering and Computer
Science, KTH Royal Institute of Technology, Stockholm 10044, Sweden
| | - Göran Stemme
- Division
of Micro and Nanosystems, School of Electrical Engineering and Computer
Science, KTH Royal Institute of Technology, Stockholm 10044, Sweden
| | - Frank Niklaus
- Division
of Micro and Nanosystems, School of Electrical Engineering and Computer
Science, KTH Royal Institute of Technology, Stockholm 10044, Sweden
| | - Kristinn B. Gylfason
- Division
of Micro and Nanosystems, School of Electrical Engineering and Computer
Science, KTH Royal Institute of Technology, Stockholm 10044, Sweden
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5
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Peterson KA, Francis RM, Banach CA, Bradley AM, Burton SD, Erickson JD, Lockwood SP, Jensen KL, Yokosuk MO, Johnson TJ, Myers TL. Method to derive the infrared complex refractive indices n(λ) and k(λ) for organic solids from KBr pellet absorption measurements. APPLIED OPTICS 2024; 63:1553-1565. [PMID: 38437368 DOI: 10.1364/ao.514661] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 01/23/2024] [Indexed: 03/06/2024]
Abstract
Obtaining the complex refractive index vectors n(ν~) and k(ν~) allows calculation of the (infrared) reflectance spectrum that is obtained from a solid in any of its many morphological forms. We report an adaptation to the KBr pellet technique using two gravimetric dilutions to derive quantitative n(ν~)/k(ν~) for dozens of powders with greater repeatability. The optical constants of bisphenol A and sucrose are compared to those derived by other methods, particularly for powdered materials. The variability of the k values for bisphenol A was examined by 10 individual measurements, showing an average coefficient of variation for k peak heights of 5.6%. Though no established standards exist, the pellet-derived k peak values of bisphenol A differ by 11% and 31% from their single-angle- and ellipsometry-derived values, respectively. These values provide an initial estimate of the precision and accuracy of complex refractive indices that can be derived using this method. Limitations and advantages of the method are discussed, the salient advantage being a more rapid method to derive n/k for those species that do not readily form crystals or specular pellets.
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6
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Delli Santi MG, Castrignano S, Capezzuto M, Consales M, Vaiano P, Cusano A, Gagliardi G, Malara P. Optrode-Assisted Multiparametric Near-Infrared Spectroscopy for the Analysis of Liquids. SENSORS (BASEL, SWITZERLAND) 2024; 24:729. [PMID: 38339446 PMCID: PMC10857342 DOI: 10.3390/s24030729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 02/12/2024]
Abstract
We demonstrate a sensing scheme for liquid analytes that integrates multiple optical fiber sensors in a near-infrared spectrometer. With a simple optofluidic method, a broadband radiation is encoded in a time-domain interferogram and distributed to different sensing units that interrogate the sample simultaneously; the spectral readout of each unit is extracted from its output signal by a Fourier transform routine. The proposed method allows performing a multiparametric analysis of liquid samples in a compact setup where the radiation source, measurement units, and spectral readout are all integrated in a robust telecom optical fiber. An experimental validation is provided by combining a plasmonic nanostructured fiber probe and a transmission cuvette in the setup and demonstrating the simultaneous measurement of the absorption spectrum and the refractive index of water-methanol solutions.
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Affiliation(s)
- Maria Giulia Delli Santi
- Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (CNR-INO), Via Campi Flegrei 34, 80078 Pozzuoli, Italy; (M.G.D.S.); (M.C.); (G.G.); (P.M.)
| | - Salvatore Castrignano
- Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (CNR-INO), Via Campi Flegrei 34, 80078 Pozzuoli, Italy; (M.G.D.S.); (M.C.); (G.G.); (P.M.)
| | - Marialuisa Capezzuto
- Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (CNR-INO), Via Campi Flegrei 34, 80078 Pozzuoli, Italy; (M.G.D.S.); (M.C.); (G.G.); (P.M.)
| | - Marco Consales
- Optoelectronics Group, Engineering Department, University of Sannio, C.so Garibaldi 107, 82100 Benevento, Italy; (M.C.); (P.V.); (A.C.)
| | - Patrizio Vaiano
- Optoelectronics Group, Engineering Department, University of Sannio, C.so Garibaldi 107, 82100 Benevento, Italy; (M.C.); (P.V.); (A.C.)
| | - Andrea Cusano
- Optoelectronics Group, Engineering Department, University of Sannio, C.so Garibaldi 107, 82100 Benevento, Italy; (M.C.); (P.V.); (A.C.)
| | - Gianluca Gagliardi
- Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (CNR-INO), Via Campi Flegrei 34, 80078 Pozzuoli, Italy; (M.G.D.S.); (M.C.); (G.G.); (P.M.)
| | - Pietro Malara
- Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (CNR-INO), Via Campi Flegrei 34, 80078 Pozzuoli, Italy; (M.G.D.S.); (M.C.); (G.G.); (P.M.)
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7
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Izquierdo-García E, Rovira A, Forcadell J, Bosch M, Marchán V. Exploring Structural-Photophysical Property Relationships in Mitochondria-Targeted Deep-Red/NIR-Emitting Coumarins. Int J Mol Sci 2023; 24:17427. [PMID: 38139255 PMCID: PMC10743691 DOI: 10.3390/ijms242417427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 11/29/2023] [Accepted: 12/07/2023] [Indexed: 12/24/2023] Open
Abstract
Organic fluorophores operating in the optical window of biological tissues, namely in the deep-red and near-infrared (NIR) region of the electromagnetic spectrum, offer several advantages for fluorescence bioimaging applications owing to the appealing features of long-wavelength light, such as deep tissue penetration, lack of toxicity, low scattering, and reduced interference with cellular autofluorescence. Among these, COUPY dyes based on non-conventional coumarin scaffolds display suitable photophysical properties and efficient cellular uptake, with a tendency to accumulate primarily in mitochondria, which renders them suitable probes for bioimaging purposes. In this study, we have explored how the photophysical properties and subcellular localization of COUPY fluorophores can be modulated through the modification of the coumarin backbone. While the introduction of a strong electron-withdrawing group, such as the trifluoromethyl group, at position 4 resulted in an exceptional photostability and a remarkable redshift in the absorption and emission maxima when combined with a julolidine ring replacing the N,N-dialkylaminobenzene moiety, the incorporation of a cyano group at position 3 dramatically reduced the brightness of the resulting fluorophore. Interestingly, confocal microscopy studies in living HeLa cells revealed that the 1,1,7,7-tetramethyl julolidine-containing derivatives accumulated in the mitochondria with much higher specificity. Overall, our results provide valuable insights for the design and optimization of new COUPY dyes operating in the deep-red/NIR region.
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Affiliation(s)
- Eduardo Izquierdo-García
- Secció de Química Orgànica, Departament de Química Inorgànica i Orgànica, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona (UB), Carrer Martí i Franquès 1-11, E-08028 Barcelona, Spain
| | - Anna Rovira
- Secció de Química Orgànica, Departament de Química Inorgànica i Orgànica, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona (UB), Carrer Martí i Franquès 1-11, E-08028 Barcelona, Spain
| | - Joan Forcadell
- Secció de Química Orgànica, Departament de Química Inorgànica i Orgànica, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona (UB), Carrer Martí i Franquès 1-11, E-08028 Barcelona, Spain
| | - Manel Bosch
- Unitat de Microscòpia Òptica Avançada, Centres Científics i Tecnològics de la Universitat de Barcelona (CCiTUB), Universitat de Barcelona (UB), Avinguda Diagonal 643, E-08028 Barcelona, Spain
| | - Vicente Marchán
- Secció de Química Orgànica, Departament de Química Inorgànica i Orgànica, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona (UB), Carrer Martí i Franquès 1-11, E-08028 Barcelona, Spain
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8
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Zhu X, Song M, Liu X, Liu W, Pan Y, Cao J, Zhang G, Yang Y, Shi Y, Wu W. Highly sensitive temperature and refractive index sensor based on no-core fiber cascaded with a balloon-shaped bent single-mode fiber. APPLIED OPTICS 2023; 62:9266-9273. [PMID: 38108697 DOI: 10.1364/ao.504976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 11/13/2023] [Indexed: 12/19/2023]
Abstract
A highly sensitive temperature and refractive index (RI) sensor based on no-core fiber (NCF) cascaded with a balloon-shaped bent single-mode fiber (BSBSF) is proposed and demonstrated. The NCF can excite higher-order modes which will be concentrated and transmitted into the BSBSF due to the characteristic of self-imaging effect. The BSBSF has an excellent temperature performance due to the high thermo-optical coefficient and thermal expansion coefficient of the polymer coating. The NCF and BSBSF are both conducive to the excitation of higher-order modes, which induces the sensitivity of the sensor with an efficiency improvement. The experimental results show that the maximum temperature sensitivity is -3.19n m/ ∘ C in the range of 22°C-83°C, which is the highest temperature sensitivity in the cascaded BSBSF structure to our best knowledge. In addition, the maximum RI sensitivity is 232.16 nm/RIU when the RI changes from 1.3234 to 1.3512. Compared with other cascaded BSBSF structures, this sensor has a higher temperature sensitivity and can be applicated in the prospects of food, biology, and environmental monitoring.
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9
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Li J, Hong T, Yu D, Che K, Chen L. Fiber laser cascaded with an MZ interferometer for simultaneous measurement of temperature and refractive index. APPLIED OPTICS 2023; 62:9119-9124. [PMID: 38108749 DOI: 10.1364/ao.505516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 11/03/2023] [Indexed: 12/19/2023]
Abstract
A fiber laser with strong spontaneous emission and high signal-to-noise ratio is proposed and experimentally demonstrated for simultaneous measurement of temperature and refractive index (RI). By cascading a single MZ interferometer, the power and the emission spectrum of the fiber laser are modulated by surrounding temperature and RI. The dual parameters are determined from the measured power change and interference dip shift. A temperature sensitivity of 0.146 dB/°C (-0.06n m/∘ C) in the range from 20°C to 90°C at an RI of 1.3910 and an RI sensitivity of -156.07d B/R I U (153.70 nm/RIU) in the range from 1.3333 to 1.3910 at 20°C are achieved.
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10
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Huang J, Cheddah S, Ma Y, Wang Y. Highly-accurate solvent identification using dynamic evaporation reflection spectra from an inverse opal sensor combined with a deep learning model. NANOSCALE 2023; 15:17422-17433. [PMID: 37855430 DOI: 10.1039/d3nr02807k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
Developing a low-cost, rapid, and highly accurate method for detecting solvents with similar structures and properties is highly demanded. In recent years, methods based on dynamic reflection spectroscopy have been developed to distinguish isomers and homologues. However, these methods heavily rely on responsive photonic crystals that can interact intricately with the solvent. In this work, we propose a deep learning approach for direct solvent identification from dynamic evaporative reflection spectra (DERS) obtained on a simple inverse opal (IO) sensor. The sensor was prepared using co-assembly and sacrificial template methods. Then, a dataset was constructed with 985 DERS obtained from 14 different solvents. Different classical machine learning and deep learning algorithms were employed for classifying these DERS. The results showed that ResNet18-CBAM, an improved convolutional neural network, outperformed all other algorithms, achieving 97.7 ± 0.9% on the 5-fold cross-validation set and 100% accuracy on the test set. This strategy presents not only a simple, efficient, and repeatable method for solvent detection but also, more importantly, by integrating the deep learning model, it allows an automatic, rapid, and accurate analysis of DERS data without the need for human intervention. It holds great application prospects in the field of solvent detection.
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Affiliation(s)
- Jin Huang
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Soumia Cheddah
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Yinjie Ma
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Yan Wang
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.
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11
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Puthiyottil N, Palamparambil A, Kaladi Chondath S, Varanakkottu SN, Menamparambath MM. Interfacial Tension-Impelled Self-Assembly and Morphology Tuning of Poly(3,4-ethylene dioxythiophene)/Tellurium Nanocomposites at Various Liquid/Liquid Interfaces. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37874771 DOI: 10.1021/acsami.3c11726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
Compared to the enormous number of nanostructures that have been documented, the variety of nanostructures produced by organic polymerization is rather limited. We devised an unconventional route and a sustainable approach to distribute tellurium nanoparticles (Te NPs) in a poly(3,4-ethylene dioxythiophene) (PEDOT) matrix to form semiconducting organic-inorganic nanocomposites for potential applications in electrochemical sensing. The adopted strategy of in situ liquid/liquid interface-assisted polymerization aids in the formation of intimately tethered Te NPs on the PEDOT polymer chains, thereby preventing the aggregation of Te NPs. The untapped versatility inherent to using biphasic systems for interfacial polymerization is explored at three interface systems of immiscible solvents: chloroform/water, dichloromethane/water, and hexane/water, giving rise to PEDOT/Te nanocomposite (PTeNC) of distinct morphology. Chemical nature, crystallinity, and morphology investigations proved the successful formation of PTeNC in different interface systems. Consequently, the temporal evolution of interfacial tension in the preferential adsorption of nanoparticles and final product morphology was monitored by pendant drop tensiometry. Owing to the role of morphology, PTeNC synthesized at the hexane/water interface showcased the best electrocatalytic behavior toward nonenzymatic detection of l-ascorbic acid, an essential nutritional factor, and a neuromodulator with a limit of detection of 0.66 μM and excellent sensitivity, selectivity, and reproducibility. Hence, we envision that interface-assisted polymerization offers a nascent and robust strategy for encapsulating unusual electrode materials in polymeric matrices.
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Affiliation(s)
- Nesleena Puthiyottil
- Department of Chemistry, National Institute of Technology Calicut, Calicut, Kerala 673601, India
| | - Ananya Palamparambil
- Department of Chemistry, National Institute of Technology Calicut, Calicut, Kerala 673601, India
| | - Subin Kaladi Chondath
- Department of Chemistry, National Institute of Technology Calicut, Calicut, Kerala 673601, India
| | | | - Mini Mol Menamparambath
- Department of Chemistry, National Institute of Technology Calicut, Calicut, Kerala 673601, India
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12
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Miyamura S, Oe R, Nakahara T, Koresawa H, Okada S, Taue S, Tokizane Y, Minamikawa T, Yano TA, Otsuka K, Sakane A, Sasaki T, Yasutomo K, Kajisa T, Yasui T. Rapid, high-sensitivity detection of biomolecules using dual-comb biosensing. Sci Rep 2023; 13:14541. [PMID: 37752134 PMCID: PMC10522648 DOI: 10.1038/s41598-023-41436-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 08/26/2023] [Indexed: 09/28/2023] Open
Abstract
Rapid, sensitive detection of biomolecules is important for biosensing of infectious pathogens as well as biomarkers and pollutants. For example, biosensing of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still strongly required for the fight against coronavirus disease 2019 (COVID-19) pandemic. Here, we aim to achieve the rapid and sensitive detection of SARS-CoV-2 nucleocapsid protein antigen by enhancing the performance of optical biosensing based on optical frequency combs (OFC). The virus-concentration-dependent optical spectrum shift produced by antigen-antibody interactions is transformed into a photonic radio-frequency (RF) shift by a frequency conversion between the optical and RF regions in the OFC, facilitating rapid and sensitive detection with well-established electrical frequency measurements. Furthermore, active-dummy temperature-drift compensation with a dual-comb configuration enables the very small change in the virus-concentration-dependent signal to be extracted from the large, variable background signal caused by temperature disturbance. The achieved performance of dual-comb biosensing will greatly enhance the applicability of biosensors to viruses, biomarkers, environmental hormones, and so on.
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Affiliation(s)
- Shogo Miyamura
- Graduate School of Advanced Technology and Science, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Ryo Oe
- Graduate School of Advanced Technology and Science, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Takuya Nakahara
- Graduate School of Advanced Technology and Science, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Hidenori Koresawa
- Graduate School of Advanced Technology and Science, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Shota Okada
- Graduate School of Sciences and Technology for Innovation, Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Shuji Taue
- School of System Engineering, Kochi University of Technology, 185 Miyanokuchi, Tosayamada, Kami, Kochi, 782-8502, Japan
| | - Yu Tokizane
- Division of Next-Generation Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Takeo Minamikawa
- Division of Interdisciplinary Researches for Medicine and Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Taka-Aki Yano
- Division of Next-Generation Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
| | - Kunihiro Otsuka
- Division of Interdisciplinary Researches for Medicine and Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
- Department of Immunology and Parasitology, Graduate School of Medicine, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Ayuko Sakane
- Division of Interdisciplinary Researches for Medicine and Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
- Department of Biochemistry, Graduate School of Medicine, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Takuya Sasaki
- Division of Interdisciplinary Researches for Medicine and Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
- Department of Biochemistry, Graduate School of Medicine, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Koji Yasutomo
- Division of Interdisciplinary Researches for Medicine and Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan
- Department of Immunology and Parasitology, Graduate School of Medicine, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Taira Kajisa
- Division of Interdisciplinary Researches for Medicine and Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan.
- Graduate School of Interdisciplinary New Science, Toyo University, 2100 Kujirai, Kawagoe, Saitama, 350-8585, Japan.
| | - Takeshi Yasui
- Division of Next-Generation Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 2-1 Minami-Josanjima, Tokushima, Tokushima, 770-8506, Japan.
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13
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Catalano E, Vallifuoco R, Zeni L, Dufour A, Marin E, Girard S, Minardo A. Tuning of the Brillouin scattering properties in microstructured optical fibers by liquid infiltration. Sci Rep 2023; 13:10468. [PMID: 37380718 DOI: 10.1038/s41598-023-37345-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 06/20/2023] [Indexed: 06/30/2023] Open
Abstract
We demonstrate the possibility to modify the Brillouin scattering properties of a microstructured pure-silica core optical fiber, by infiltrating a liquid inside its holes. In particular, we show that the dependence of the Brillouin frequency shift (BFS) on the temperature can be reduced by infiltration, owing to the large negative thermo-optic coefficient of the liquid. Infiltrating a chloroform-acetonitrile mixture with a refractive index of 1.365 inside the holes of a suspended-core fiber with a core diameter of 3 µm, the BFS temperature sensing coefficient is reduced by ≈ 21%, while the strain sensitivity remains almost unaltered. Besides tuning the temperature sensing coefficient, the proposed platform could find other applications in Brillouin sensing, such as distributed electrical and magnetic measurements, or enhanced Brillouin gain in fibers infiltrated with high nonlinear optical media.
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Affiliation(s)
- Ester Catalano
- Department of Engineering, Università della Campania Luigi Vanvitelli, Via Roma 29, 81031, Aversa, Italy
| | - Raffaele Vallifuoco
- Department of Engineering, Università della Campania Luigi Vanvitelli, Via Roma 29, 81031, Aversa, Italy
| | - Luigi Zeni
- Department of Engineering, Università della Campania Luigi Vanvitelli, Via Roma 29, 81031, Aversa, Italy
| | - Alexis Dufour
- Laboratoire Hubert Curien, UMR CNRS 5516, 18 Rue du Professeur Benoît Lauras, 42000, Saint-Etienne, France
| | - Emmanuel Marin
- Laboratoire Hubert Curien, UMR CNRS 5516, 18 Rue du Professeur Benoît Lauras, 42000, Saint-Etienne, France
| | - Sylvain Girard
- Laboratoire Hubert Curien, UMR CNRS 5516, 18 Rue du Professeur Benoît Lauras, 42000, Saint-Etienne, France
| | - Aldo Minardo
- Department of Engineering, Università della Campania Luigi Vanvitelli, Via Roma 29, 81031, Aversa, Italy.
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14
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Cheng W, Sun X, Ye S, Yuan B, Xiong J, Liu X, Sun Y, Marsh JH, Hou L. Double slot micro ring resonators with inner wall angular gratings as ultra-sensitive biochemical sensors. OPTICS EXPRESS 2023; 31:20034-20048. [PMID: 37381406 DOI: 10.1364/oe.483990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 05/16/2023] [Indexed: 06/30/2023]
Abstract
We simulate and demonstrate experimentally an inner-wall grating double slot micro ring resonator (IG-DSMRR) with a center slot ring radius of only 6.72 µm based on the silicon-on-insulator platform. This novel photonic-integrated sensor for optical label-free biochemical analysis boosts the measured refractive index (RI) sensitivity in glucose solutions to 563 nm/RIU with the limit of detection value being 3.7 × 10-6 RIU (refractive index units). The concentration sensitivity for sodium chloride solutions can reach 981 pm/%, with a minimum concentration detection limit of 0.02%. Using the combination of DSMRR and IG, the detection range is enlarged significantly to 72.62 nm, three times the free spectral range of conventional slot micro ring resonators. The measured Q-factor is 1.6 × 104, and the straight strip and double slot waveguide transmission losses are 0.9 dB/cm and 20.2 dB/cm, respectively. This IG-DSMRR combines the advantages of a micro ring resonator, slot waveguide, and angular grating and is highly desirable for biochemical sensing in liquids and gases offering an ultra-high sensitivity and ultra-large measurement range. This is the first report of a fabricated and measured double-slot micro ring resonator with an inner sidewall grating structure.
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15
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Li J, Jiang S, Aberdeen S, Lee SS. Highly Efficient Refractive Index Sensor Based on a Dual-Side Polished SMS Fiber Enabled by Femtosecond Laser Writing. SENSORS (BASEL, SWITZERLAND) 2023; 23:3651. [PMID: 37050709 PMCID: PMC10099056 DOI: 10.3390/s23073651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 03/29/2023] [Accepted: 03/30/2023] [Indexed: 06/19/2023]
Abstract
Fiber-optic refractive index (RI) sensors based on wavelength-shift-based interrogation continue to present a challenge in achieving high sensitivity for a wide detection range. In this paper, we propose a sensor for determining the RI of liquids based on femtosecond laser (fs-laser) writing of a dual-side polished singlemode-multimode-singlemode (SMS) fiber. The proposed sensor can determine the RI value of a surrounding liquid by detecting the dip wavelength in the transmission spectrum of the light propagating through the sensing area. The high RI sensitivity is attributed to the increased interaction area established by the fs-laser, which creates hydrophilic surfaces and maintains the wide detection range of the SMS structure. The results of the wavelength-shift-based interrogation reveal that the fabricated device exhibited a high sensitivity of 161.40 nm per refractive index unit (RIU) over a wide RI detection range of 0.062 RIU. The proposed device has high processing accuracy and a simple manufacturing process. Hence, it has the potential to be used as a lab-on-fiber sensing platform in chemical and biotechnological applications.
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Affiliation(s)
- Jinke Li
- Department of Electronic Engineering, Kwangwoon University, Seoul 01897, Republic of Korea
- Nano Device Application Center, Kwangwoon University, Seoul 01897, Republic of Korea
| | - Shiru Jiang
- Department of Electronic Engineering, Kwangwoon University, Seoul 01897, Republic of Korea
- Nano Device Application Center, Kwangwoon University, Seoul 01897, Republic of Korea
| | - Stuart Aberdeen
- Nano Device Application Center, Kwangwoon University, Seoul 01897, Republic of Korea
| | - Sang-Shin Lee
- Department of Electronic Engineering, Kwangwoon University, Seoul 01897, Republic of Korea
- Nano Device Application Center, Kwangwoon University, Seoul 01897, Republic of Korea
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16
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Haase BE, Hennig J, Kutas M, Waller E, Hering J, von Freymann G, Molter D. Phase-quadrature quantum imaging with undetected photons. OPTICS EXPRESS 2023; 31:143-152. [PMID: 36606956 DOI: 10.1364/oe.471837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 10/10/2022] [Indexed: 06/17/2023]
Abstract
Sensing with undetected photons allows access to spectral regions with simultaneous detection of photons of another region and is based on nonlinear interferometry. To obtain the full information of a sample, the corresponding interferogram has to be analyzed in terms of amplitude and phase, which has been realized so far by multiple measurements followed by phase variation. Here, we present a polarization-optics-based phase-quadrature implementation in a nonlinear interferometer for imaging with undetected photons in the infrared region. This allows us to obtain phase and visibility with a single image acquisition without the need of varying optical paths or phases, thus enabling the detection of dynamic processes. We demonstrate the usefulness of our method on a static phase mask opaque to the detected photons as well as on dynamic measurement tasks as the drying of an isopropanol film and the stretching of an adhesive tape.
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17
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Porolnik W, Kasprzycka M, Podciechowska K, Teubert A, Piskorz J. Synthesis and spectroscopic properties of novel dipyrrole and tetrapyrrole-based photosensitizers with various biphenylyl substituents. Tetrahedron 2022. [DOI: 10.1016/j.tet.2022.133088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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18
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Ryu JH, Yang H, Park S, Kim S, Han K, Kim H, Cho K, Lee KB. PLC-Based Integrated Refractive Index Sensor Probe with Partially Exposed Waveguide. SENSORS 2022; 22:s22155672. [PMID: 35957229 PMCID: PMC9370853 DOI: 10.3390/s22155672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/18/2022] [Accepted: 07/26/2022] [Indexed: 11/16/2022]
Abstract
This paper proposes a simple, high-efficiency refractive index (RI) sensor, with a structure based on the planar lightwave circuit (PLC) probe type. The optical sensor has a 1 × 2 splitter structure with reference and sensing channels, each consisting of a U-shaped waveguide structure that is configured by connecting C bends. This design allows for the sensor device to have a probe structure wherein the surface interconnected with activity devices (i.e., an optical source and optical detector) is placed on one side. The reference channel is bent with a minimum optical loss, and the sensing channel has a bent structure, involving a C-bend waveguide with a maximum loss. The C-bend waveguide with a maximum loss is conformally aligned to have a trench structure with the same bending radius, designed to selectively expose the sidewall of the core layer. The local index contrast varies depending on the material in contact with the trench, resulting in a change in the optical output power of the waveguide. The sensitivity of the proposed sensor was 0 and 2070 μW/refractive index unit (RIU) for the reference and sensing channels, respectively, as the RI changed from 1.385 to 1.445 at a 1550 nm wavelength. These results suggest that the proposed structure enables efficient RI measurement through the use of a simple dip-type method.
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19
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Heinsalu S, Utaka K. Sensitivity Improvement of Multi-Slot Subwavelength Bragg Grating Refractive Index Sensors by Increasing the Waveguide Height or Suspending the Sensor. SENSORS 2022; 22:s22114136. [PMID: 35684757 PMCID: PMC9185276 DOI: 10.3390/s22114136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 05/25/2022] [Accepted: 05/27/2022] [Indexed: 02/05/2023]
Abstract
We present two methods of improving wavelength sensitivity for multi-slot sub-wavelength Bragg grating (MS-SW BG) refractive index sensors. The sensor structure is designed to have high optical mode confinement in the gaps between the silicon pillars whereby the surrounding medium interaction is high, thus improving the sensitivity. Further sensitivity improvements are achieved by increasing the waveguide height or suspending the sensor. The second option, sensor suspension, additionally requires supporting modifications in which case various configurations are considered. After the optimization of the parameters the sensors were fabricated. For the case of a waveguide height increase to 500 nm, the sensitivity of 850 nm/RIU was obtained; for sensor suspension with fully etched holes, 922 nm/RIU; for the case of not fully etched holes, 1100 nm/RIU; with the sensor lengths of about 10 µm for all cases. These values show improvements by 16.5%, 25%, and 50.5%, respectively, compared to the previous result where the height was fixed to 340 nm.
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20
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Roldán-Varona P, Lomer M, Algorri JF, Rodríguez-Cobo L, López-Higuera JM. Enhanced refractometer for aqueous solutions based on perfluorinated polymer optical fibres. OPTICS EXPRESS 2022; 30:1397-1409. [PMID: 35209301 DOI: 10.1364/oe.448111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 12/13/2021] [Indexed: 06/14/2023]
Abstract
The use of the new CYTOP (Cyclized Transparent Optical Polymer) fibres for the inscription of optical structures and the detection of different parameters has started to gain importance in the past decade. This work presents the design, simulation and manufacture of a CYTOP-based surrounding refractive index sensor for aqueous solutions, given its high sensitivity in the range 1.315 - 1.333 (at 1550 nm wavelength). The structure is based on a bent and polished fibre (in order to increase its sensitivity), the polished area being the surface on which a diffraction grating is inscribed with a femtosecond laser. The interaction of the field propagated by the fibre with the grating causes diffraction of certain orders towards the outside, depending, among other things, on the refractive index of the fluid. In addition to a maximum sensitivity of -208.8 nm/RIU and a remarkable insensitivity to temperature, it offers a spectral fingerprint of each sensed fluid.
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21
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Pfalzgraf I, Suntsov S, Kip D. Multiplexing temperature-compensated open-cavity Fabry-Perot sensors at a fiber tip. APPLIED OPTICS 2021; 60:10402-10408. [PMID: 34807050 DOI: 10.1364/ao.438565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 10/27/2021] [Indexed: 06/13/2023]
Abstract
We investigate multiplexing of four highly sensitive Fabry-Perot (FP) microresonators at the tip of a single-mode optical fiber for refractive index (RI) measurements with simultaneous temperature compensation. The individual sensing elements for RI or temperature consist of either open-cavity FP resonators or solid fiber core regions fabricated by diamond-blade dicing of single-mode optical fibers, respectively. The reflectivity of the open resonators is further enhanced by matched dielectric coatings. At the same time, the solid core resonators formed by the fiber pieces between the open cavities are used as thermometers. This allows immediate compensation for temperature cross-sensitivity during RI measurements. The general performance of the sensor is demonstrated by measuring the RI of sucrose solutions, where we use phase tracking of the characteristic Fourier transform components of the backreflected optical spectrum for evaluation. The temperature sensitivity is on average 20±/∘C with an accuracy of 0.01°C, fully sufficient for biomedical applications. Meanwhile, the four RI sensing (open) cavities show high sensitivity of approximately 1160 nm/RIU. Due to the compact size of the sensor, small spatial inhomogeneities of RI can be accurately detected. If the cavities are additionally filled with molecularly imprinted polymers or coated with thin functional layers, they could also be used for the detection of trace substances in biomedical laboratory-on-a-fiber applications.
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22
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Laser nano-filament explosion for enabling open-grating sensing in optical fibre. Nat Commun 2021; 12:6344. [PMID: 34732710 PMCID: PMC8566495 DOI: 10.1038/s41467-021-26671-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 10/15/2021] [Indexed: 11/08/2022] Open
Abstract
Embedding strong photonic stopbands into traditional optical fibre that can directly access and sense the outside environment is challenging, relying on tedious nano-processing steps that result in fragile thinned fibre. Ultrashort-pulsed laser filaments have recently provided a non-contact means of opening high-aspect ratio nano-holes inside of bulk transparent glasses. This method has been extended here to optical fibre, resulting in high density arrays of laser filamented holes penetrating transversely through the silica cladding and guiding core to provide high refractive index contrast Bragg gratings in the telecommunication band. The point‐by‐point fabrication was combined with post-chemical etching to engineer strong photonic stopbands directly inside of the compact and flexible fibre. Fibre Bragg gratings with sharply resolved π-shifts are presented for high resolution refractive index sensing from \documentclass[12pt]{minimal}
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\begin{document}$${n}_{{{{{{\rm{H}}}}}}}$$\end{document}nH = 1 to 1.67 as the nano-holes were readily wetted and filled with various solvents and oils through an intact fibre cladding. Engineered stop bands to sense an ambient environment can enable many applications. Here, the authors demonstrate well-controlled processes to open high-aspect ratio nanoholes through optical fibre for Bragg gratings in the telecomm spectrum and to enable high-resolution refractive index sensing
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23
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Larson K, Hammond A, Carver C, Anderson D, Viglione M, Boaks M, Nordin G, Camacho RM. Post-fabrication tuning of microring resonators using 3D-printed microfluidics. OPTICS LETTERS 2021; 46:4650-4653. [PMID: 34525073 PMCID: PMC9362736 DOI: 10.1364/ol.433987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
We demonstrate a method of tuning the resonant frequencies of silicon microring resonators using a 3D-printed microfluidic chip overlaid directly on the photonic circuit with zero energy consumption following the initial tuning. Aqueous solutions with different concentrations of NaCl are used in experimentation. A shift of a full free spectral range is observed at a concentration of 10% NaCl. On a 60 µm microring resonator, this equals a resonant wavelength shift of 1.514 nm when the index of the cladding changes by 0.017 refractive index units (RIUs), or at a rate of 89.05 nm/RIU.
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Affiliation(s)
- Kevin Larson
- Department of Electrical and Computer Engineering, Brigham Young University, Provo UT 84604
| | - Alec Hammond
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta GA 30332
| | - Christian Carver
- Department of Electrical and Computer Engineering, Brigham Young University, Provo UT 84604
| | - Derek Anderson
- Department of Electrical and Computer Engineering, Brigham Young University, Provo UT 84604
| | - Matthew Viglione
- Department of Electrical and Computer Engineering, Brigham Young University, Provo UT 84604
| | - Mawla Boaks
- Department of Electrical and Computer Engineering, Brigham Young University, Provo UT 84604
| | - Greg Nordin
- Department of Electrical and Computer Engineering, Brigham Young University, Provo UT 84604
| | - Ryan M. Camacho
- Department of Electrical and Computer Engineering, Brigham Young University, Provo UT 84604
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24
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Díaz-Cruz EB, Regalado-Pérez E, Santos J, Hu H. Development of SnS/PVP core/shell quantum dots with tunable color emission synthesized by microwave heating. J SOLID STATE CHEM 2021. [DOI: 10.1016/j.jssc.2021.122264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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25
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Haron MH, Berhanuddin DD, Majlis BY, Md Zain AR. Double-peak one-dimensional photonic crystal cavity in parallel configuration for temperature self-compensation in sensing. APPLIED OPTICS 2021; 60:1667-1673. [PMID: 33690503 DOI: 10.1364/ao.418646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 01/05/2021] [Indexed: 06/12/2023]
Abstract
We designed and demonstrated a double-peak one-dimensional photonic crystal (1D PhC) cavity device by integrating two 1D PhCs cavities in a parallel configuration. The device design is proposed so that it can be used for bio-sensing purposes and has a self-compensation ability to reduce the measurement error caused by the change of the surrounding temperature. By combining two light resonances, two resonance peaks are obtained. The peak's separation, which gives the initial value for a sensing system, can be controlled by varying the cavity length difference (Δc) between the first and second 1D PhCs in parallel. Then, by making one arm of the device as the reference arm and the other arm as the sensing arm, the temperature self-compensation device can be realized. The design and simulation of this device are done by using Lumerical software, which are Lumerical MODE, Lumerical finite-difference time-domain, and Lumerical Interconnect. Electron-beam-lithography and deep reactive-ion-etching processes were used for device fabrication. The experimental results show the controllable peaks' separation, which solves the double-peak requirement for a temperature self-compensated bio-sensor design.
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26
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Leuermann J, Stamenkovic V, Ramirez-Priego P, Sánchez-Postigo A, Fernández-Gavela A, Chapman CA, Bailey RC, Lechuga LM, Perez-Inestrosa E, Collado D, Halir R, Molina-Fernández Í. Coherent silicon photonic interferometric biosensor with an inexpensive laser source for sensitive label-free immunoassays. OPTICS LETTERS 2020; 45:6595-6598. [PMID: 33325848 DOI: 10.1364/ol.411635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 11/09/2020] [Indexed: 06/12/2023]
Abstract
Over the past two decades, integrated photonic sensors have been of major interest to the optical biosensor community due to their capability to detect low concentrations of molecules with label-free operation. Among these, interferometric sensors can be read-out with simple, fixed-wavelength laser sources and offer excellent detection limits but can suffer from sensitivity fading when not tuned to their quadrature point. Recently, coherently detected sensors were demonstrated as an attractive alternative to overcome this limitation. Here we show, for the first time, to the best of our knowledge, that this coherent scheme provides sub-nanogram per milliliter limits of detection in C-reactive protein immunoassays and that quasi-balanced optical arm lengths enable operation with inexpensive Fabry-Perot-type lasers sources at telecom wavelengths.
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27
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An Approach to Ring Resonator Biosensing Assisted by Dielectrophoresis: Design, Simulation and Fabrication. MICROMACHINES 2020; 11:mi11110954. [PMID: 33105846 PMCID: PMC7690605 DOI: 10.3390/mi11110954] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 12/12/2022]
Abstract
The combination of extreme miniaturization with a high sensitivity and the potential to be integrated in an array form on a chip has made silicon-based photonic microring resonators a very attractive research topic. As biosensors are approaching the nanoscale, analyte mass transfer and bonding kinetics have been ascribed as crucial factors that limit their performance. One solution may be a system that applies dielectrophoretic forces, in addition to microfluidics, to overcome the diffusion limits of conventional biosensors. Dielectrophoresis, which involves the migration of polarized dielectric particles in a non-uniform alternating electric field, has previously been successfully applied to achieve a 1000-fold improved detection efficiency in nanopore sensing and may significantly increase the sensitivity in microring resonator biosensing. In the current work, we designed microring resonators with integrated electrodes next to the sensor surface that may be used to explore the effect of dielectrophoresis. The chip design, including two different electrode configurations, electric field gradient simulations, and the fabrication process flow of a dielectrohoresis-enhanced microring resonator-based sensor, is presented in this paper. Finite element method (FEM) simulations calculated for both electrode configurations revealed ∇E2 values above 1017 V2m−3 around the sensing areas. This is comparable to electric field gradients previously reported for successful interactions with larger molecules, such as proteins and antibodies.
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28
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Piskorz J, Porolnik W, Kucinska M, Dlugaszewska J, Murias M, Mielcarek J. BODIPY-Based Photosensitizers as Potential Anticancer and Antibacterial Agents: Role of the Positive Charge and the Heavy Atom Effect. ChemMedChem 2020; 16:399-411. [PMID: 32964632 DOI: 10.1002/cmdc.202000529] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/18/2020] [Indexed: 12/24/2022]
Abstract
Boron-dipyrromethene derivatives, including cationic and iodinated analogs, were obtained and subjected to physicochemical and in vitro photodynamic activity studies. Iodinated derivatives revealed a substantial heavy atom effect manifested by a bathochromic shift of the absorption band by about 30 nm and fluorescence intensity reduced by about 30-35 times, compared to that obtained for non-iodinated ones. In consequence, singlet oxygen generation significantly increased with ΦΔ values in the range 0.69-0.97. The in vitro photodynamic activity was evaluated on Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli, and on human androgen-sensitive prostate adenocarcinoma cells (LNCaP). The novel cationic, iodinated BODIPY, demonstrated the highest activity toward all studied cells. An excellent cytotoxic effect was found against LNCaP cells with an IC50 value of 19.3 nM, whereas the viability of S. aureus was reduced by >5.6 log10 at 0.25 μM concentration and by >5.3 log10 in the case of E. coli at 5 μM. Thus, this analog seems to be a very promising candidate for the application in both anticancer and antimicrobial photodynamic therapy.
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Affiliation(s)
- Jaroslaw Piskorz
- Chair and Department of Inorganic and Analytical Chemistry, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780 Poznan, Poland
| | - Weronika Porolnik
- Chair and Department of Inorganic and Analytical Chemistry, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780 Poznan, Poland
| | - Malgorzata Kucinska
- Chair and Department of Toxicology, Poznan University of Medical Sciences, Poznań, Dojazd 30 Street, 60-631 Poznan, Poland
| | - Jolanta Dlugaszewska
- Chair and Department of Genetics and Pharmaceutical Microbiology, Poznan University of Medical Sciences, Swiecickiego, Poznań, 4, 60-781 Poznan, Poland
| | - Marek Murias
- Chair and Department of Toxicology, Poznan University of Medical Sciences, Poznań, Dojazd 30 Street, 60-631 Poznan, Poland
| | - Jadwiga Mielcarek
- Chair and Department of Inorganic and Analytical Chemistry, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780 Poznan, Poland
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29
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Wang F, Song D, Dickie DA, Fraser CL. Multi-Stimuli Responsive Luminescent β-Diketones and Difluoroboron Complexes with Heterocyclic Substituents. J Fluoresc 2020; 31:39-49. [PMID: 33052508 DOI: 10.1007/s10895-020-02626-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 09/24/2020] [Indexed: 12/01/2022]
Abstract
Emissive β-diketones (bdks) and difluoroboron complexes (BF2bdks) exhibit multi-stimuli responsive luminescence, including solvatochromism, viscochromism, aggregation induced emission, thermal and mechanochromic luminescence, halochromism and pH sensing. In this study, a series of six-membered heterocycle-substituted (piperidine, morpholine, 1-methyl piperazine) bdk ligands and boron complexes were synthesized, and their luminescent properties were investigated. All the compounds exhibited red-shifted emission in more polar solvents due to intramolecular charge transfer as well as higher emission intensity in more viscous environments. In response to solubility changes in water/tetrahydrofuran mixtures, while the piperazine bdk ligand showed aggregation caused quenching, the piperidine and morpholine bdks displayed enhanced emission upon aggregation. In the solid state, all ligands exhibited mechanochromism. More dramatic halochromism was observed for the piperidine boron dye spin cast film. In solution, for the boron dyes under varying pH values (1-13), different protonated and deprotonated forms were analyzed according to the measured emission spectra. Graphical abstract Multi-stimuli responsive luminescent properties were investigated for the six-membered heterocycle-substituted β-diketone ligands and difluoroboron complexes.
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Affiliation(s)
- Fang Wang
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA
| | - Daniel Song
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA
| | - Cassandra L Fraser
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA.
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Heinsalu S, Isogai Y, Matsushima Y, Ishikawa H, Utaka K. Record-high sensitivity compact multi-slot sub-wavelength Bragg grating refractive index sensor on SOI platform. OPTICS EXPRESS 2020; 28:28126-28139. [PMID: 32988090 DOI: 10.1364/oe.402672] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 08/28/2020] [Indexed: 06/11/2023]
Abstract
In this paper, a high sensitivity compact multi-slot sub-wavelength Bragg grating refractive index (RI) sensor was investigated. The structural parameters were optimized for higher sensitivity to RI change of the surrounding medium from viewpoints of a wavelength shift, an extinction ratio and a transmission loss, and a record-high sensitivity was experimentally demonstrated with a compact size. In this sensor, the first side-lobe at the Bragg grating (BG) stop-band end was focused as a sensing peak wavelength for moderate transmission loss and efficient sensing. To realize the compactness, a period count of the BG was kept as small as 20. By increasing the RI of the surrounding medium, the sensing peak shifts toward a longer wavelength side; thus due to the high sharpness and easy tracing of the first side-lobe, the device worked as an efficient RI sensor. The structural optimization was carried out by using 3D finite-difference time-domain (FDTD) simulation approach, and also influences of the structural parameters to sensitivities were discussed. Based on these optimized parameters, the devices were fabricated using the lift-off technique. By exposing the sensor to various liquid samples with different RIs such as pure water, sugar-dissolved water with various concentrations, acetone and isopropyl alcohol (IPA), a record-high sensitivity of 730 nm/RIU was attained for a sensor fabricated on SOI platforms with a length of as small as 9.5 µm and a transmission loss of 3 dB.
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31
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Graphene oxide integrated silicon photonics for detection of vapour phase volatile organic compounds. Sci Rep 2020; 10:9592. [PMID: 32533065 PMCID: PMC7293283 DOI: 10.1038/s41598-020-66389-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 05/17/2020] [Indexed: 11/09/2022] Open
Abstract
The optical response of a graphene oxide integrated silicon micro-ring resonator (GOMRR) to a range of vapour phase Volatile Organic Compounds (VOCs) is reported. The response of the GOMRR to all but one (hexane) of the VOCs tested is significantly higher than that of the uncoated (control) silicon MRR, for the same vapour flow rate. An iterative Finite Difference Eigenmode (FDE) simulation reveals that the sensitivity of the GO integrated device (in terms of RIU/nm) is enhanced by a factor of ~2, which is coupled with a lower limit of detection. Critically, the simulations reveal that the strength of the optical response is determined by molecular specific changes in the local refractive index probed by the evanescent field of the guided optical mode in the device. Analytical modelling of the experimental data, based on Hill-Langmuir adsorption characteristics, suggests that these changes in the local refractive index are determined by the degree of molecular cooperativity, which is enhanced for molecules with a polarity that is high, relative to their kinetic diameter. We believe this reflects a molecular dependent capillary condensation within the graphene oxide interlayers, which, when combined with highly sensitive optical detection, provides a potential route for discriminating between different vapour phase VOCs.
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Ouellette F, Li J, Ou Z, Albert J. High-resolution interrogation of tilted fiber Bragg gratings using an extended range dual wavelength differential detection. OPTICS EXPRESS 2020; 28:14662-14676. [PMID: 32403503 DOI: 10.1364/oe.391375] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
An extended range dual wavelength differential detection technique for interrogating fiber Bragg grating sensors is implemented for the measurement of tilted fiber Bragg gratings. The dynamic chirp of a single DFB laser diode modulated with a square wave is used to generate two pairs of wavelengths, in the high and low modulation states, with a separation approximately equal to the bandwidth of the TFBG, resulting in a doubling of the range of the DWDD measurement. A spectral resolution of 0.08 pm and a refractive index resolution of 9.9 × 10-6 are obtained over a range of refractive index of 3.7 × 10-2, corresponding to 11.9 bits of resolution.
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Sizov VS, Komissar DA, Metlina DA, Aminev DF, Ambrozevich SA, Nefedov SE, Varaksina EA, Metlin MT, Mislavskií VV, Taydakov IV. Effect of ancillary ligands on visible and NIR luminescence of Sm 3+β-diketonate complexes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 225:117503. [PMID: 31577985 DOI: 10.1016/j.saa.2019.117503] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/28/2019] [Accepted: 08/29/2019] [Indexed: 06/10/2023]
Abstract
Two new Sm3+ complexes with pyrazolic β-diketones bearing a CF3 group acting as main ligands and with 2,2'-bipyridine or 1,10-phenanthroline being the ancillary ligand were studied, and their energy level structure was established. Stark splitting observed in the photoluminescence spectra of the complexes points to their non-cubic symmetry, confirmed by the calculated Judd-Ofelt intensity parameters. Internal quantum yields obtained for the compounds by the Judd-Ofelt calculations were of the order of 5.5%, whereas the measured external quantum yields were 0.75% and 1.5% for Sm3+ complexes involving 2,2'-bipyridine and 1,10-phenanthroline ancillary ligands, respectively, with the corresponding sensitization efficiencies calculated as 0.16 and 0.26. It was demonstrated that replacing the 1,10-phenanthroline ancillary ligand with 2,2'-bipyridine provides an increase in the intensity of 650 nm emission of the Sm3+ complexes, with the branching ratio reaching 55%. Intensive emission of the studied complexes at 650 nm offers hope for their use as spectrally pure red emitters.
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Affiliation(s)
- V S Sizov
- P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninsky Prospekt, Moscow 119991, Russian Federation; Bauman Moscow State Technical University, 5/1 2-ya Baumanskaya St., 105005 Moscow, Russian Federation.
| | - D A Komissar
- P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninsky Prospekt, Moscow 119991, Russian Federation; Moscow Institute of Physics and Technology (State University), 9 Institutskiy per., Dolgoprudny 141700, Moscow Region, Russian Federation
| | - D A Metlina
- P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninsky Prospekt, Moscow 119991, Russian Federation
| | - D F Aminev
- P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninsky Prospekt, Moscow 119991, Russian Federation
| | - S A Ambrozevich
- P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninsky Prospekt, Moscow 119991, Russian Federation; Moscow Institute of Physics and Technology (State University), 9 Institutskiy per., Dolgoprudny 141700, Moscow Region, Russian Federation; Bauman Moscow State Technical University, 5/1 2-ya Baumanskaya St., 105005 Moscow, Russian Federation
| | - S E Nefedov
- Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, 31 Leninsky Prospekt, Moscow 119991, Russian Federation
| | - E A Varaksina
- P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninsky Prospekt, Moscow 119991, Russian Federation; Moscow Institute of Physics and Technology (State University), 9 Institutskiy per., Dolgoprudny 141700, Moscow Region, Russian Federation; A.N. Nesmeyanov Institute of Organoelement Compounds of the Russian Academy of Sciences, 28 Vavilova St., Moscow 119991, Russian Federation
| | - M T Metlin
- P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninsky Prospekt, Moscow 119991, Russian Federation; Bauman Moscow State Technical University, 5/1 2-ya Baumanskaya St., 105005 Moscow, Russian Federation
| | - V V Mislavskií
- Moscow Institute of Physics and Technology (State University), 9 Institutskiy per., Dolgoprudny 141700, Moscow Region, Russian Federation
| | - I V Taydakov
- P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninsky Prospekt, Moscow 119991, Russian Federation
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Han X, Liu C, Jiang S, Leng S, Yang J. Up-down Taper Based In-Fiber Mach-Zehnder Interferometer for Liquid Refractive Index Sensing. SENSORS 2019; 19:s19245440. [PMID: 31835516 PMCID: PMC6960560 DOI: 10.3390/s19245440] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 12/05/2019] [Accepted: 12/05/2019] [Indexed: 11/16/2022]
Abstract
A novel in-fiber Mach-Zehnder interferometer based on cascaded up-down-taper (UDT) structure is proposed by sandwiching a piece of polarization maintaining fiber between two single-mode fibers (SMF) and by utilizing over-fusion splicing method. The dual up tapers respectively act as fiber splitter/combiner, the down taper acts as an optical attenuator. The structure parameters are analyzed and optimized. A larger interference fringe extinction ratio ~15 dB is obtained to achieve refractive index (RI) sensing based on intensity demodulation. The experimental results show that the RI sensitivity is -310.40 dB/RIU with the linearity is improved to 0.99 in the range of 1.3164-1.3444. The corresponding resolution can reach 3.22 × 10-5 RIU, which is 6.8 times higher than wavelength demodulation. The cross sensitivity which caused by temperature fluctuation is less than 1.4 × 10-4.
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Affiliation(s)
- Xiaopeng Han
- College of Electronics Engineering, Heilongjiang University, Harbin 150080, China; (X.H.); (S.J.); (S.L.)
| | - Chunyu Liu
- College of Electronics Engineering, Heilongjiang University, Harbin 150080, China; (X.H.); (S.J.); (S.L.)
- Key Lab of Electronics Engineering, College of Heilongjiang Province, Heilongjiang University, Harbin 150080, China;
- Correspondence: ; Tel.: +86-139-0481-5763
| | - Shengxu Jiang
- College of Electronics Engineering, Heilongjiang University, Harbin 150080, China; (X.H.); (S.J.); (S.L.)
| | - Shuo Leng
- College of Electronics Engineering, Heilongjiang University, Harbin 150080, China; (X.H.); (S.J.); (S.L.)
| | - Jiuru Yang
- Key Lab of Electronics Engineering, College of Heilongjiang Province, Heilongjiang University, Harbin 150080, China;
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Luan E, Yun H, Ma M, Ratner DM, Cheung KC, Chrostowski L. Label-free biosensing with a multi-box sub-wavelength phase-shifted Bragg grating waveguide. BIOMEDICAL OPTICS EXPRESS 2019; 10:4825-4838. [PMID: 31565528 PMCID: PMC6757469 DOI: 10.1364/boe.10.004825] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 08/20/2019] [Accepted: 08/20/2019] [Indexed: 05/02/2023]
Abstract
Sub-wavelength grating (SWG) metamaterials have been considered to provide promising solutions in the development of next-generation photonic integrated circuits. In recent years, increasied interest has been paid to silicon photonic planar biosensors based on SWG geometries for performance enhancement. In this work, we demonstrate a highly sensitive label-free phase-shifted Bragg grating (PSBG) sensing configuration, which consists of sub-wavelength block arrays in both propagation and transverse directions. By introducing salt serial dilutions and electrostatic polymers assays, bulk and surface sensitivities of the proposed sensor are characterized, obtaining measured results up to 579.2 nm/RIU and 1914 pm/nm, respectively. Moreover, the proposed multi-box PSBG sensor presents an improved quality factor as high as ∼ 8000 , roughly 3-fold of the microring-based counterpart, which further improves the detection limit. At last, by employing a biotin-streptavidin affinity assay, the capability for small molecule monitoring is exemplified with a minimum detectable concentration of biotin down to 2.28 × 10 - 8 M .
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Affiliation(s)
- Enxiao Luan
- Department of Electrical and Computer Engineering, The University of British Columbia, 2332 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Han Yun
- Department of Electrical and Computer Engineering, The University of British Columbia, 2332 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Minglei Ma
- Department of Electrical and Computer Engineering, The University of British Columbia, 2332 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Daniel M. Ratner
- Department of Bioengineering, University of Washington, 3720 15th Ave NE Seattle, WA 98195-5061, USA
| | - Karen C. Cheung
- Department of Electrical and Computer Engineering, The University of British Columbia, 2332 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Lukas Chrostowski
- Department of Electrical and Computer Engineering, The University of British Columbia, 2332 Main Mall, Vancouver, BC, V6T 1Z4, Canada
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Leuermann J, Fernández-Gavela A, Torres-Cubillo A, Postigo S, Sánchez-Postigo A, Lechuga LM, Halir R, Molina-Fernández Í. Optimizing the Limit of Detection of Waveguide-Based Interferometric Biosensor Devices. SENSORS 2019; 19:s19173671. [PMID: 31450817 PMCID: PMC6749351 DOI: 10.3390/s19173671] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/16/2019] [Accepted: 08/21/2019] [Indexed: 01/13/2023]
Abstract
Waveguide-based photonic sensors provide a unique combination of high sensitivity, compact size and label-free, multiplexed operation. Interferometric configurations furthermore enable a simple, fixed-wavelength read-out making them particularly suitable for low-cost diagnostic and monitoring devices. Their limit of detection, i.e., the lowest analyte concentration that can be reliably observed, mainly depends on the sensors response to small refractive index changes, and the noise in the read-out system. While enhancements in the sensors response have been extensively studied, noise optimization has received much less attention. Here we show that order-of-magnitude enhancements in the limit of detection can be achieved through systematic noise reduction, and demonstrate a limit of detection of ∼10−8RIU with a silicon nitride sensor operating at telecom wavelengths.
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Affiliation(s)
- Jonas Leuermann
- Bionand Center for Nanomedicine and Biotechnology, Parque Tecnológico de Andalucía, 29590 Málaga, Spain.
- Department de Ingeniería de Comunicaciones, Universidad de Málaga, ETSI Telecomunicación, Campus de Teatinos, 29071 Málaga, Spain.
| | | | - Antonia Torres-Cubillo
- Department de Ingeniería de Comunicaciones, Universidad de Málaga, ETSI Telecomunicación, Campus de Teatinos, 29071 Málaga, Spain
| | - Sergio Postigo
- Department de Ingeniería Mecánica, Universidad de Málaga, Térmica y de Fluidos, Escuela de Ingenierías Industriales, Campus de Teatinos, 29071 Málaga, Spain
| | - Alejandro Sánchez-Postigo
- Department de Ingeniería de Comunicaciones, Universidad de Málaga, ETSI Telecomunicación, Campus de Teatinos, 29071 Málaga, Spain
| | - Laura M Lechuga
- Nanobiosensors and Bioanalytical Applications Group, Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC, BIST and CIBER-BBN Campus UAB, 08193 Barcelona, Spain
| | - Robert Halir
- Bionand Center for Nanomedicine and Biotechnology, Parque Tecnológico de Andalucía, 29590 Málaga, Spain
- Department de Ingeniería de Comunicaciones, Universidad de Málaga, ETSI Telecomunicación, Campus de Teatinos, 29071 Málaga, Spain
| | - Íñigo Molina-Fernández
- Bionand Center for Nanomedicine and Biotechnology, Parque Tecnológico de Andalucía, 29590 Málaga, Spain
- Department de Ingeniería de Comunicaciones, Universidad de Málaga, ETSI Telecomunicación, Campus de Teatinos, 29071 Málaga, Spain
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37
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Knoerzer M, Szydzik C, Ren G, Huertas CS, Palmer S, Tang P, Nguyen TG, Bui L, Boes A, Mitchell A. Optical frequency comb based system for photonic refractive index sensor interrogation. OPTICS EXPRESS 2019; 27:21532-21545. [PMID: 31510229 DOI: 10.1364/oe.27.021532] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 06/28/2019] [Indexed: 06/10/2023]
Abstract
In this contribution, we demonstrate how an optical frequency comb can be used to enhance the functionality of an integrated photonic biosensor platform. We show that if an optical frequency comb is used to sample the spectral response of a Mach-Zehnder interferometer and if the line spacing is arranged to sample the periodic response at 120° intervals, then it is possible to combine these samples into a single measurement of the interferometer phase. This phase measurement approach is accurate, independent of the bias of the interferometer and robust against intensity fluctuations that are common to each of the comb lines. We demonstrate this approach with a simple silicon photonic interferometric refractive index sensor and show that the benefits of our approach can be obtained without degrading the lower limit of detection of 3.70×10-7 RIU.
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38
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Jiang Y, Wang T, Liu C, Feng D, Jiang B, Yang D, Zhao J. Simultaneous measurement of refractive index and temperature with high sensitivity based on a multipath fiber Mach-Zehnder interferometer. APPLIED OPTICS 2019; 58:4085-4090. [PMID: 31158165 DOI: 10.1364/ao.58.004085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 04/19/2019] [Indexed: 06/09/2023]
Abstract
We present and experimentally demonstrate a highly sensitive sensor for simultaneously measuring the refractive index (RI) and temperature based on a multipath fiber Mach-Zehnder interferometer. The sensor is fabricated by sandwiching a segment of weak-coupling seven-core fiber (SCF) with two short multimode fibers, and then splicing it with lead-in and lead-out single-mode fibers, respectively. Six outer cores of the SCF are half-etched chemically for enhancing the interaction between light and matter. A high-quality transmission spectrum with 23 dB fringe visibility is obtained. Due to the strong interaction between the outer core modes and cladding modes with the surrounding medium, the proposed fiber structure exhibits not only an extremely high RI sensitivity of -1802.26 nm/RI unit from 1.427 to 1.442, but also a superior temperature sensitivity of 82 pm/°C from 10°C to 90°C. Moreover, RI and temperature can be discriminated simultaneously by measuring the central wavelength shifts of two transmission notches. This sensor has outstanding advantages of high sensitivity, easy fabrication, simple structure, and low cost, and may find applications in multiparameter highly sensitive sensing.
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39
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A thermodynamic investigation of solute - solvent interactions through volumetric, ultrasonic, dielectric, refractive and excess properties of binary mixtures of Tri-n-butyl phosphate with dichloro, trichloro and tetrachloromethane at 298.15 K. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.01.155] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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40
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Wang F, Song D, Dickie DA, Fraser CL. Ring Size Effects on Multi‐Stimuli Responsive Luminescent Properties of Cyclic Amine Substituted β‐Diketones and Difluoroboron Complexes. Chem Asian J 2019; 14:1849-1859. [DOI: 10.1002/asia.201801576] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 12/21/2018] [Indexed: 12/17/2022]
Affiliation(s)
- Fang Wang
- Department of Chemistry University of Virginia Charlottesville VA 22904 USA
| | - Daniel Song
- Department of Chemistry University of Virginia Charlottesville VA 22904 USA
| | - Diane A. Dickie
- Department of Chemistry University of Virginia Charlottesville VA 22904 USA
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41
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Moock P, Kasper L, Jäger M, Stolarek D, Richter H, Bruns J, Petermann K. TDM-controlled ring resonator arrays for fast, fixed-wavelength optical biosensing. OPTICS EXPRESS 2018; 26:22356-22365. [PMID: 30130930 DOI: 10.1364/oe.26.022356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/19/2018] [Indexed: 06/08/2023]
Abstract
A novel control concept for serial ring resonator arrays based on a time-division multiplex (TDM) approach is presented. It allows fast sampling rates in terms of biological kinetics. The novelty consists of using both thermal tuning of the effective refractive index and thermo-optical multiplexing for the silicon-on-insulator (SOI) ring resonator arrays, without the need for a tunable laser source. Using a fixed wavelength, fast read-out rates of 100 Hz are demonstrated for each ring.
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42
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Bernini R, Persichetti G, Catalano E, Zeni L, Minardo A. Refractive index sensing by Brillouin scattering in side-polished optical fibers. OPTICS LETTERS 2018; 43:2280-2283. [PMID: 29762572 DOI: 10.1364/ol.43.002280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 04/09/2018] [Indexed: 06/08/2023]
Abstract
In this Letter, we demonstrate the possibility to measure the refractive index of a liquid, using the stimulating Brillouin scattering in a 3-cm-long side-polished optical fiber. In addition, we show that by depositing a high-refractive index layer on the polished surface the sensitivity of the Brillouin frequency shift (BFS) can be increased due to a higher penetration of the evanescent field in the outer medium. Experiments show a maximum BFS change of about 11 MHz when varying the refractive index of the external medium from 1 (air) to 1.402, and a BFS sensitivity to refractive index of about 293 MHz/RIU around 1.40.
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Prasad PR, Selvaraja SK, Varma M. Real-time compensation of errors in refractive index shift measurements of microring sensors using thermo-optic coefficients. OPTICS EXPRESS 2018; 26:13461-13473. [PMID: 29801371 DOI: 10.1364/oe.26.013461] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 03/07/2018] [Indexed: 06/08/2023]
Abstract
We report a method for compensation of errors caused by temperature fluctuations in refractive index measurements using Silicon photonic microring sensors. The method involves determination of resonance wavelength shifts caused by thermal fluctuations using real-time measurement of on-chip temperature variations and thermo-optic coefficient (TOC) of analyte liquids. Resistive metal lines patterned around Silicon microrings are used to track temperature variations and TOC of analyte is calculated by measuring wavelength shifts caused by controlled increments in device temperature. The TOC of de-ionized water is determined to be -1.12 × 10-4/°C, with an accuracy of ±8.26 × 10-6/°C. In our system, chip-surface temperature variations were measured with an instrument limited precision of 0.004 °C yielding a factor of 16 enhancement in tracking accuracy compared to conventional, bottom-of-chip temperature measurement. We show that refractive index detection limit of the microring sensor is also improved by the same factor.
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44
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Apriyanto H, Ravet G, Bernal OD, Cattoen M, Seat HC, Chavagnac V, Surre F, Sharp JH. Comprehensive Modeling of Multimode Fiber Sensors for Refractive Index Measurement and Experimental Validation. Sci Rep 2018; 8:5912. [PMID: 29651039 PMCID: PMC5897385 DOI: 10.1038/s41598-018-24153-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 03/27/2018] [Indexed: 11/17/2022] Open
Abstract
We propose and develop a comprehensive model for estimating the refractive index (RI) response over three potential sensing zones in a multimode fiber. The model has been developed based on a combined ray optics, Gaussian beam, and wave optics analysis coupled to the consideration of the injected interrogating lightwave characteristics and validated experimentally through the realization of three sensors with different lengths of stripped cladding sections as the sensing region. The experimental results highly corroborate and validate the simulation output from the model for the three RI sensing zones. The sensors can be employed over a very wide dynamic RI range from 1.316 to over 1.608 at a wavelength of 1550 nm, with the best resolution of 2.2406 × 10−5 RI unit (RIU) obtained in Zone II for a 1-cm sensor length.
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Affiliation(s)
- Haris Apriyanto
- LAAS-CNRS, Université de Toulouse, CNRS, INP, Toulouse, France.,Politeknik Negeri Indramayu, Indramayu, Indonesia
| | - Gautier Ravet
- LAAS-CNRS, Université de Toulouse, CNRS, INP, Toulouse, France
| | | | - Michel Cattoen
- LAAS-CNRS, Université de Toulouse, CNRS, INP, Toulouse, France
| | - Han Cheng Seat
- LAAS-CNRS, Université de Toulouse, CNRS, INP, Toulouse, France.
| | - Valérie Chavagnac
- GET - UMR5563, OMP, Université de Toulouse, CNRS, IRD, Toulouse, France
| | - Frederic Surre
- School of Mathematics, Computer Science and Engineering, University of London, London, UK
| | - James H Sharp
- Systems, Power and Energy Research Division, School of Engineering, University of Glasgow, Glasgow, G12 8QQ, UK
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45
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Saunders JE, Chen H, Brauer C, Clayton M, Loock HP. Two distinct mechanisms upon absorption of volatile organic compounds into siloxane polymers. SOFT MATTER 2018; 14:2206-2218. [PMID: 29431812 DOI: 10.1039/c7sm02234d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The response of polysiloxane materials to volatile organic compounds (VOCs) including benzene, toluene, ethylbenzene, and toluene (BTEX), as well as cyclohexane, acetone, methanol and isopropanol is studied using thin film large-angle refractometry. Refractive index and thickness changes are measured to quantify the diffusion rate and partition coefficients associated with the absorption and desorption of VOC vapours into polydimethylsiloxane (PDMS) and polydiphenylsiloxane (PDPS) - PDMS copolymer films. Absorption of volatile solvent vapours into siloxane polymers is found to follow two distinct mechanisms with different absorption rates. These mechanisms are also associated with different excess volumes of mixing and may be accompanied by a polymer restructuring step.
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Affiliation(s)
- John E Saunders
- Department of Chemistry, Queen's University Kingston, ON K7L 3N6, Canada.
| | - Hao Chen
- Department of Chemistry, Queen's University Kingston, ON K7L 3N6, Canada.
| | - Chris Brauer
- Department of Chemistry, Queen's University Kingston, ON K7L 3N6, Canada.
| | - McGregor Clayton
- Department of Chemistry, Queen's University Kingston, ON K7L 3N6, Canada.
| | - Hans-Peter Loock
- Department of Chemistry, Queen's University Kingston, ON K7L 3N6, Canada.
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Datta A, Saha A, Shukla A. Investigation of modal-interference-induced fiber optic refractive index sensor: markedly enhanced sensitivity realized by shining an optical vortex beam. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2017; 34:2034-2045. [PMID: 29091655 DOI: 10.1364/josaa.34.002034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 10/03/2017] [Indexed: 06/07/2023]
Abstract
A highly sensitive multimode-interference-based refractive index sensor is reported here by shining an optical vortex beam. The sensor probe is formed by splicing a length of no-core fiber in between two air-core vortex fibers. The coupling characteristics of various modes inside the sensor and their effect on sensing properties are numerically analyzed. Simulation results show that the sensing scheme proffers a maximum sensing resolution of 7.59×10-6 and 4.18×10-6 RIU for no-core fiber length of 29.40 and 44.60 mm, respectively. Because of its high sensitivity, the study has potential applications in the chemical and biological sensing fields.
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Jiang B, Zhou K, Wang C, Zhao Y, Zhao J, Zhang L. Temperature-calibrated high-precision refractometer using a tilted fiber Bragg grating. OPTICS EXPRESS 2017; 25:25910-25918. [PMID: 29041253 DOI: 10.1364/oe.25.025910] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 10/06/2017] [Indexed: 06/07/2023]
Abstract
We present a refractometer with main- and vernier-scale to measure the refractive index (RI) of liquids with high precision by using the fine spectrum structure of a tilted fiber Bragg grating (TFBG). The absolute RI values are determined by the accurate wavelength of cut-off mode resonances. The main- and vernier-scale are calibrated by measuring large groups of fine spectra at different cut-off mode resonances in a small RI range, and the use of vernier-scale certainly reduces the RI measurement uncertainty resulted from the discrete cladding mode resonances. The performance of the TFBG-based vernier refractometer is experimentally verified by exploring the temperature dependence of RI of anhydrous ethanol in a near infrared region, showing an enhanced accuracy to the order of 10-4, high repeatability and temperature self-calibration capability.
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Wang F, DeRosa CA, Daly ML, Song D, Fraser CL. Multi-stimuli responsive luminescent azepane-substituted β-diketones and difluoroboron complexes. MATERIALS CHEMISTRY FRONTIERS 2017; 1:1866-1874. [PMID: 29774165 PMCID: PMC5951180 DOI: 10.1039/c7qm00137a] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Difluoroboron β-diketonate (BF2bdk) compounds show environment-sensitive optical properties in solution, aggregation-induced emission (AIE) and multi-stimuli responsive fluorescence switching in the solid state. Here, a series of 4-azepane-substituted β-diketone (bdk) ligands (L-H, L-OMe, L-Br) and their corresponding difluoroboron dyes (D-H, D-OMe, D-Br) were synthesized, and various responsive fluorescence properties of the compounds were studied, including solvatochromism, viscochromism, AIE, mechanochromic luminescence (ML) and halochromism. Compared to the β-diketones, the boron complexes exhibited higher extinction coefficients but lower quantum yields, and red-shifted absorption and emission in CH2Cl2. Computational studies showed that intramolecular charge transfer (ICT) dominated rather than π-π* transitions in all the compounds regardless of boron coordination. In solution, all the bdk ligands and boron dyes showed red-shifted emission in more polar solvents and increased fluorescence intensity in more viscous media. Upon aggregation, the emission of the β-diketones was quenched, however, the boronated dyes showed increased emission, indicative of AIE. Solid-state emission properties, ML and halochromism, were investigated on spin cast films. For ML, smearing caused a bathochromic emission shift for L-Br, and powder X-ray diffraction (XRD) patterns showed that the "as spun" and thermally annealed states were more crystalline and the smeared state was amorphous. No obvious ML emission shift was observed for L-H or L-OMe, and the boronated dyes were not mechano-active. Trifluoroacetic acid (TFA) and triethylamine (TEA) vapors were used to study halochromism. Large hypsochromic emission shifts were observed for all the compounds after TFA vapor was applied, and reversible fluorescence switching was achieved using the acid/base pair.
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Affiliation(s)
- Fang Wang
- Department of Chemistry, University of Virginia, Charlottesville,
Virginia 22904
| | | | - Margaret L. Daly
- Department of Chemistry, University of Virginia, Charlottesville,
Virginia 22904
| | - Daniel Song
- Department of Chemistry, University of Virginia, Charlottesville,
Virginia 22904
| | - Cassandra L. Fraser
- Department of Chemistry, University of Virginia, Charlottesville,
Virginia 22904
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Urbonas D, Balčytis A, Vaškevičius K, Gabalis M, Petruškevičius R. Air and dielectric bands photonic crystal microringresonator for refractive index sensing. OPTICS LETTERS 2016; 41:3655-3658. [PMID: 27472642 DOI: 10.1364/ol.41.003655] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present the experimental and numerical analysis of a microring resonator with an integrated one-dimensional photonic crystal fabricated on a silicon-on-insulator platform and show its applicability in bulk refractive index sensing. The photonic crystal is formed by periodically patterned, partially etched cylindrical perforations, whose induced photonic bandgap is narrower than the range of measurable wavelengths (1520-1620 nm). Of particular interest is that the microring operates in both air and dielectric bands, and the sensitivities of the resonances on both edges of the bandgap were investigated. We showed that a higher field localization inside the volume of the perforations for the air band mode leads to an increase in sensitivity.
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Andrews NLP, Ross R, Munzke D, van Hoorn C, Brzezinski A, Barnes JA, Reich O, Loock HP. In-fiber Mach-Zehnder interferometer for gas refractive index measurements based on a hollow-core photonic crystal fiber. OPTICS EXPRESS 2016; 24:14086-14099. [PMID: 27410569 DOI: 10.1364/oe.24.014086] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We describe an in-fiber interferometer based on a gas-filled hollow-core photonic crystal fiber. Expressions for the sensitivity, figure of merit and refractive index resolution are derived, and values are experimentally measured and theoretically validated using mode field calculations. The refractive indices of nine monoatomic and molecular gases are measured with a resolution of δns < 10-6.
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