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Mahalanabish A, Huang SH, Shvets G. Inverted Transflection Spectroscopy of Live Cells Using Metallic Grating on Elevated Nanopillars. ACS Sens 2024; 9:1218-1226. [PMID: 38470457 DOI: 10.1021/acssensors.3c02031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Water absorption of mid-infrared (MIR) radiation severely limits the options for vibrational spectroscopy of the analytes-including live biological cells-that must be probed in aqueous environments. While internal reflection elements, such as attenuated total reflection prisms and metasurfaces, partially overcome this limitation, such devices have their own limitations: ATR prisms are difficult to integrate with multiwell cell culture workflows, while metasurfaces suffer from a limited spectral range and small penetration depth into analytes. In this work, we introduce an alternative live cell biosensing platform based on metallic nanogratings fabricated on top of elevated dielectric pillars. For the MIR wavelengths that are significantly longer than the grating period, reflection-based spectroscopy enables broadband sensing of the analytes inside the trenches separating the dielectric pillars. Because the depth of the analyte twice-traversed by the MIR light excludes the highly absorbing thick water layer above the grating, we refer to the technique as inverted transflection spectroscopy (ITS). The analytic power of ITS is established by measuring a wide range of protein concentrations in solution, with the limit of detection in the single-digit mg mL-1. The ability of ITS to interrogate live cells that naturally wrap themselves around the grating is used to characterize their adhesion kinetic.
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Affiliation(s)
- Aditya Mahalanabish
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Steven H Huang
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Gennady Shvets
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
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2
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Chesi G, Falcone V, Calcaterra S, Virgilio M, Frigerio J. Modelling second harmonic generation at mid-infrared frequencies in waveguide integrated Ge/SiGe quantum wells. OPTICS EXPRESS 2023; 31:17098-17111. [PMID: 37381452 DOI: 10.1364/oe.483888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 03/26/2023] [Indexed: 06/30/2023]
Abstract
A promising alternative to bulk materials for the nonlinear coupling of optical fields is provided by photonic integrated circuits based on heterostructures made of asymmetric-coupled quantum wells. These devices achieve a huge nonlinear susceptivity but are affected by strong absorption. Here, driven by the technological relevance of the SiGe material system, we focus on Second-Harmonic Generation in the mid-infrared spectral region, realized by means of Ge-rich waveguides hosting p-type Ge/SiGe asymmetric coupled quantum wells. We present a theoretical investigation of the generation efficiency in terms of phase mismatch effects and trade-off between nonlinear coupling and absorption. To maximize the SHG efficiency at feasible propagation distances, we also individuate the optimal density of quantum wells. Our results indicate that conversion efficiencies of ≈ 0.6%/W can be achieved in WGs featuring lengths of few hundreds µm only.
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3
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Morse PT, Tuck S, Kerns M, Goebel DJ, Wan J, Waddell T, Wider JM, Hüttemann CL, Malek MH, Lee I, Sanderson TH, Hüttemann M. Non-invasive treatment of ischemia/reperfusion injury: Effective transmission of therapeutic near-infrared light into the human brain through soft skin-conforming silicone waveguides. Bioeng Transl Med 2023; 8:e10496. [PMID: 37206207 PMCID: PMC10189478 DOI: 10.1002/btm2.10496] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 01/02/2023] [Accepted: 01/13/2023] [Indexed: 02/10/2023] Open
Abstract
Noninvasive delivery of near-infrared light (IRL) to human tissues has been researched as a treatment for several acute and chronic disease conditions. We recently showed that use of specific IRL wavelengths, which inhibit the mitochondrial enzyme cytochrome c oxidase (COX), leads to robust neuroprotection in animal models of focal and global brain ischemia/reperfusion injury. These life-threatening conditions can be caused by an ischemic stroke or cardiac arrest, respectively, two leading causes of death. To translate IRL therapy into the clinic an effective technology must be developed that allows efficient delivery of IRL to the brain while addressing potential safety concerns. Here, we introduce IRL delivery waveguides (IDWs) which meet these demands. We employ a low-durometer silicone that comfortably conforms to the shape of the head, avoiding pressure points. Furthermore, instead of using focal IRL delivery points via fiberoptic cables, lasers, or light-emitting diodes, the distribution of the IRL across the entire area of the IDW allows uniform IRL delivery through the skin and into the brain, preventing "hot spots" and thus skin burns. The IRL delivery waveguides have unique design features, including optimized IRL extraction step numbers and angles and a protective housing. The design can be scaled to fit various treatment areas, providing a novel IRL delivery interface platform. Using fresh (unfixed) human cadavers and isolated cadaver tissues, we tested transmission of IRL via IDWs in comparison to laser beam application with fiberoptic cables. Using the same IRL output energies IDWs performed superior in comparison to the fiberoptic delivery, leading to an up to 95% and 81% increased IRL transmission for 750 and 940 nm IRL, respectively, analyzed at a depth of 4 cm into the human head. We discuss the unique safety features and potential further improvements of the IDWs for future clinical implementation.
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Affiliation(s)
- Paul T. Morse
- Center for Molecular Medicine and GeneticsWayne State University School of MedicineDetroitMichiganUSA
| | - Samuel Tuck
- Center for Molecular Medicine and GeneticsWayne State University School of MedicineDetroitMichiganUSA
- Department of Emergency MedicineUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | | | - Dennis J. Goebel
- Department of Ophthalmology, Visual and Anatomical SciencesWayne State University School of MedicineDetroitMichiganUSA
| | - Junmei Wan
- Center for Molecular Medicine and GeneticsWayne State University School of MedicineDetroitMichiganUSA
| | - Tom Waddell
- Mitovation, Inc.Innovation Partnerships Startup Incubator University of Michigan North Campus Research ComplexAnn ArborMichiganUSA
| | - Joseph M. Wider
- Department of Emergency MedicineUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Charlotte L. Hüttemann
- Center for Molecular Medicine and GeneticsWayne State University School of MedicineDetroitMichiganUSA
| | - Moh H. Malek
- Department of Health Care SciencesEugene Applebaum College of Pharmacy & Health Sciences, Wayne State UniversityDetroitMichiganUSA
| | - Icksoo Lee
- College of MedicineDankook UniversityCheonan‐siChungcheongnam‐doRepublic of Korea
| | - Thomas H. Sanderson
- Department of Emergency MedicineUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Maik Hüttemann
- Center for Molecular Medicine and GeneticsWayne State University School of MedicineDetroitMichiganUSA
- Department of Biochemistry, Microbiology and ImmunologyWayne State UniversityDetroitMichiganUSA
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4
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Alancay MM, Lobo MO, Samman NC. Physicochemical and structural characterization of whey protein concentrate-tomato pectin conjugates. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2023. [PMID: 37029992 DOI: 10.1002/jsfa.12612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/06/2023] [Accepted: 04/08/2023] [Indexed: 06/19/2023]
Abstract
BACKGROUND Protein-pectin conjugates, obtained through a controlled Maillard reaction in blends of precursors, are studied for their contribution to improving the emulsifying and thermal properties of proteins. The objective was to obtain a conjugate between whey protein concentrate (WPC) and non-conventional pectins extracted in acid (acid tomato pectin, ATP) and aqueous medium (water tomato pectin, WTP) from industrialized tomato residues (tomato waste, TW), characterize the conjugates and study their emulsion properties. The Maillard reaction was carried out at 60 °C and 75% relative humidity in blends with 2:1 proportions; 1:1 and 1:2 (mprotein :mpectin ) for 3, 6 and 12 days. Conjugates were compared concerning treated and untreated WPC. RESULTS The WPC-ATP conjugate showed significant increases in color difference (ΔE). The electrophoresis profile of the conjugates showed diffuse bands of molecular weight between 37 and 250 kDa and a reduction in the intensity of bands characteristic of WPC (α-lactalbumin and β-lactoglobulin). Thermal analysis showed an increase in the peak temperature and a reduction in the enthalpy change in protein denaturation, associated with the formation of conjugates. The infrared spectroscopy of the conjugates, in the amide III zone (1300-1100 cm-1 ), indicated an increase in the relative peak area associated with the unfolding and exhibition of the hydrophobic zones of the WPC fraction. The emulsions formulated with the conjugates showed a significant increase in the emulsifying stability index (ESI) (P < 0.05) concerning the treated and untreated WPC emulsions. CONCLUSION The formation of conjugates increased the emulsifying properties and improved the thermal stability of WPC, showing an innovative and alternative food ingredient too. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Matias Miguel Alancay
- Facultad de Ingenieria, Universidad Nacional de Jujuy, Centro Interdisciplinario de Investigaciones en Tecnologías y Desarrollo Social para el NOA (CIITED-CONICET-Universidad Nacional de Jujuy), San Salvador de Jujuy, Argentina
| | - Manuel Oscar Lobo
- Facultad de Ingenieria, Universidad Nacional de Jujuy, Centro Interdisciplinario de Investigaciones en Tecnologías y Desarrollo Social para el NOA (CIITED-CONICET-Universidad Nacional de Jujuy), San Salvador de Jujuy, Argentina
| | - Norma Cristina Samman
- Facultad de Ingenieria, Universidad Nacional de Jujuy, Centro Interdisciplinario de Investigaciones en Tecnologías y Desarrollo Social para el NOA (CIITED-CONICET-Universidad Nacional de Jujuy), San Salvador de Jujuy, Argentina
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5
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Zhu X, Li S, Sun A, Pan Y, Liu W, Wu Y, Zhang G, Shi Y. A mid-infrared focusing grating coupler with a single circular arc element based on germanium on silicon. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2023; 14:478-484. [PMID: 37091286 PMCID: PMC10113522 DOI: 10.3762/bjnano.14.38] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 03/17/2023] [Indexed: 05/03/2023]
Abstract
A mid-infrared (MIR) focusing grating coupler (FGC) with a single circular arc element (CAE) in the front of the gratings based on a germanium-on-silicon (Ge-on-Si) platform is designed and demonstrated. It can be used equivalently to a traditional FGC with all-focusing gratings. By optimizing the structural parameters of the CAE, the combination of a tapered linear grating and the CAE can improve the coupling efficiency to 8.61%, which is twice as large as that of the traditional MIR grating couplers. To the best of our knowledge, it is the highest coupling efficiency in a full-etch grating coupler based on Ge-on-Si. Moreover, the proposed grating coupler can be used for refractive index (RI) sensing, and the maximum sensitivity is 980.7 nm/RIU when the RI changes from 1 to 1.04. By comparing with traditional grating couplers requiring secondary etching, the proposed full-etch grating coupler structure can reduce the complexity of fabrication and can provide a prospective platform for MIR photonic integration and photonic biosensor detection.
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Affiliation(s)
- Xiaojun Zhu
- School of Information Science and Technology, Nantong University, Nantong 226019, China
| | - Shuai Li
- School of Information Science and Technology, Nantong University, Nantong 226019, China
| | - Ang Sun
- School of Information Science and Technology, Nantong University, Nantong 226019, China
| | - Yongquan Pan
- School of Information Science and Technology, Nantong University, Nantong 226019, China
| | - Wen Liu
- School of Information Science and Technology, Nantong University, Nantong 226019, China
| | - Yue Wu
- School of Information Science and Technology, Nantong University, Nantong 226019, China
| | - Guoan Zhang
- School of Information Science and Technology, Nantong University, Nantong 226019, China
| | - Yuechun Shi
- Yongjiang Laboratory, Ningbo 315202, China and Nanjing University, Key Lab Intelligent Opt Sensing & Manipulat, Minist Educ, Nanjing University, Nanjing 210093, China
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6
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Barzaghi A, Falcone V, Calcaterra S, Marris-Morini D, Virgilio M, Frigerio J. Modelling of an intersubband quantum confined Stark effect in Ge quantum wells for mid-infrared photonics. OPTICS EXPRESS 2022; 30:46710-46721. [PMID: 36558616 DOI: 10.1364/oe.476735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 11/04/2022] [Indexed: 06/17/2023]
Abstract
In this work we theoretically investigate quantum confined Stark effect of intersubband transitions in asymmetric Ge/SiGe quantum wells for intensity modulation in the mid-infrared. Our calculations show that extinction ratios up to 1 dB and modulation speeds of several tens of GHz could be obtained in 100 µm long waveguides.
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7
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Li H, Zhang Y, Huang Y, Cao D, Wang S. Dissolution-enhanced emission of 1,3,6,8-tetrakis( p-benzoic acid)pyrene for selectively detecting protamine and “on-to-on” heparin detection in water. NEW J CHEM 2022. [DOI: 10.1039/d1nj03946f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A small molecule TBAPy was used as a turn-on fluorescent probe to selectively detect protamine and heparin based on the dissolution-enhanced emission (DEE) phenomenon.
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Affiliation(s)
- Hongtao Li
- State Key Laboratory of Organic–Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Yuting Zhang
- State Key Laboratory of Organic–Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Yan Huang
- State Key Laboratory of Organic–Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Dapeng Cao
- State Key Laboratory of Organic–Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Shitao Wang
- State Key Laboratory of Organic–Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China
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8
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Rowe DJ, Owens DR, Parker SL, Faust SN, Wilkinson JS, Mashanovich GZ. The Effect of Haematocrit on Measurement of the Mid-Infrared Refractive Index of Plasma in Whole Blood. BIOSENSORS 2021; 11:417. [PMID: 34821633 PMCID: PMC8616018 DOI: 10.3390/bios11110417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/21/2021] [Accepted: 10/23/2021] [Indexed: 11/20/2022]
Abstract
Recent advances suggest that miniaturised mid-infrared (MIR) devices could replace more time-consuming, laboratory-based techniques for clinical diagnostics. This work uses Fourier transform infrared spectroscopy to show that the MIR complex refractive index of whole blood varies across a range of haematocrit. This indicates that the use of an evanescent measurement is not sufficient to optically exclude the cellular content of blood in the MIR, as previously assumed. Here, spectral refractive index data is presented in two ways. First, it is given as whole blood with varying haematocrit. Second, it is given as the percentage error that haematocrit introduces to plasma. The maximum error in the effective plasma refractive index due to the haematocrit of healthy adults was 0.25% for the real part n and 11% for the imaginary part k. This implies that calibration measurements of haematocrit can be used to account for errors introduced by the cellular content, enabling plasma spectra and analyte concentrations to be indirectly calculated from a whole blood sample. This methodological advance is of clinical importance as plasma concentration of analytes such as drugs can be determined using MIR without the preprocessing of whole blood.
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Affiliation(s)
- David J. Rowe
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton SO17 1BJ, UK; (J.S.W.); (G.Z.M.)
| | - Daniel R. Owens
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO16 6YD, UK; (D.R.O.); (S.N.F.)
- NIHR Southampton Clinical Research Facility and Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Suzanne L. Parker
- UQ Centre for Clinical Research, The University of Queensland, Herston, QLD 4029, Australia;
| | - Saul N. Faust
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO16 6YD, UK; (D.R.O.); (S.N.F.)
- NIHR Southampton Clinical Research Facility and Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - James S. Wilkinson
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton SO17 1BJ, UK; (J.S.W.); (G.Z.M.)
| | - Goran Z. Mashanovich
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton SO17 1BJ, UK; (J.S.W.); (G.Z.M.)
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9
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Freitag S, Baer M, Buntzoll L, Ramer G, Schwaighofer A, Schmauss B, Lendl B. Polarimetric Balanced Detection: Background-Free Mid-IR Evanescent Field Laser Spectroscopy for Low-Noise, Long-term Stable Chemical Sensing. ACS Sens 2021; 6:35-42. [PMID: 33372759 PMCID: PMC7872502 DOI: 10.1021/acssensors.0c01342] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
![]()
In
this work, we introduce polarimetric balanced detection as a
new attenuated total reflection (ATR) infrared (IR) sensing scheme,
leveraging unequal effective thicknesses achieved with laser light
of different polarizations. We combined a monolithic widely tunable
Vernier quantum cascade laser (QCL-XT) and a multibounce ATR IR spectroscopy
setup for analysis of liquids in a process analytical setting. Polarimetric
balanced detection enables simultaneous recording of background and
sample spectra, significantly reducing long-term drifts. The root-mean-square
noise could be improved by a factor of 10 in a long-term experiment,
compared to conventional absorbance measurements obtained via the
single-ended optical channel. The sensing performance of the device
was further evaluated by on-site measurements of ethanol in water,
leading to an improved limit of detection (LOD) achieved with polarimetric
balanced detection. Sequential injection analysis was employed for
automated injection of samples into a custom-built ATR flow cell mounted
above a zinc sulfide multibounce ATR element. The QCL-XT posed to
be suitable for mid-IR-based sensing in liquids due to its wide tunability.
Polarimetric balanced detection proved to enhance the robustness and
long-term stability of the sensing device, along with improving the
LOD by a factor of 5. This demonstrates the potential for new polarimetric
QCL-based ATR mid-IR sensing schemes for in-field measurements or
process monitoring usually prone to a multitude of interferences.
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Affiliation(s)
- Stephan Freitag
- Institute of Chemical Technologies and Analytics, Technische Universität Wien, Getreidemarkt 9/164-UPA, 1060 Vienna, Austria
| | - Matthias Baer
- Institute of Microwaves and Photonics, Friedrich-Alexander-University Erlangen-Nuremberg, Cauerstr. 9, 91058 Erlangen, Germany
| | - Laura Buntzoll
- Institute of Microwaves and Photonics, Friedrich-Alexander-University Erlangen-Nuremberg, Cauerstr. 9, 91058 Erlangen, Germany
| | - Georg Ramer
- Institute of Chemical Technologies and Analytics, Technische Universität Wien, Getreidemarkt 9/164-UPA, 1060 Vienna, Austria
| | - Andreas Schwaighofer
- Institute of Chemical Technologies and Analytics, Technische Universität Wien, Getreidemarkt 9/164-UPA, 1060 Vienna, Austria
| | - Bernhard Schmauss
- Institute of Microwaves and Photonics, Friedrich-Alexander-University Erlangen-Nuremberg, Cauerstr. 9, 91058 Erlangen, Germany
| | - Bernhard Lendl
- Institute of Chemical Technologies and Analytics, Technische Universität Wien, Getreidemarkt 9/164-UPA, 1060 Vienna, Austria
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10
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Benéitez NT, Baumgartner B, Missinne J, Radosavljevic S, Wacht D, Hugger S, Leszcz P, Lendl B, Roelkens G. Mid-IR sensing platform for trace analysis in aqueous solutions based on a germanium-on-silicon waveguide chip with a mesoporous silica coating for analyte enrichment. OPTICS EXPRESS 2020; 28:27013-27027. [PMID: 32906963 DOI: 10.1364/oe.399646] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 07/25/2020] [Indexed: 06/11/2023]
Abstract
A novel platform based on evanescent wave sensing in the 6.5 to 7.5 µm wavelength range is presented with the example of toluene detection in an aqueous solution. The overall sensing platform consists of a germanium-on-silicon waveguide with a functionalized mesoporous silica cladding and integrated microlenses for alignment-tolerant back-side optical interfacing with a tunable laser spectrometer. Hydrophobic functionalization of the mesoporous cladding allows enrichment of apolar analyte molecules and prevents strong interaction of water with the evanescent wave. The sensing performance was evaluated for aqueous toluene standards resulting in a limit of detection of 7 ppm. Recorded adsorption/desorption profiles followed Freundlich adsorption isotherms with rapid equilibration and resulting sensor response times of a few seconds. This indicates that continuous monitoring of contaminants in water is possible. A significant increase in LOD can be expected by likely improvements to the spectrometer noise floor which, expressed as a relative standard deviation of 100% lines, is currently in the range of 10-2A.U.
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11
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Mittal V, Devitt G, Nedeljkovic M, Carpenter LG, Chong HMH, Wilkinson JS, Mahajan S, Mashanovich GZ. Ge on Si waveguide mid-infrared absorption spectroscopy of proteins and their aggregates. BIOMEDICAL OPTICS EXPRESS 2020; 11:4714-4722. [PMID: 32923073 PMCID: PMC7449756 DOI: 10.1364/boe.398013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 07/19/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
Specific proteins and their aggregates form toxic amyloid plaques and neurofibrillary tangles in the brains of people suffering from neurodegenerative diseases such as Alzheimer's and Parkinson's. It is important to study these conformational changes to identify and differentiate these diseases at an early stage so that timely medication is provided to patients. Mid-infrared spectroscopy can be used to monitor these changes by studying the line-shapes and the relative absorbances of amide bands present in proteins. This work focusses on the spectroscopy of the protein, Bovine Serum Albumin as an exemplar, and its aggregates using germanium on silicon waveguides in the 1900-1000 cm-1 (5.3-10.0 µm) spectral region.
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Affiliation(s)
- Vinita Mittal
- Optoelectronics Research Centre, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - George Devitt
- Institute for Life Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Milos Nedeljkovic
- Optoelectronics Research Centre, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Lewis G. Carpenter
- Optoelectronics Research Centre, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Harold M. H. Chong
- School of Electronics and Computer Science, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - James S. Wilkinson
- Optoelectronics Research Centre, University of Southampton, Southampton, SO17 1BJ, United Kingdom
- Institute for Life Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Sumeet Mahajan
- Institute for Life Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom
- School of Chemistry, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Goran Z. Mashanovich
- Optoelectronics Research Centre, University of Southampton, Southampton, SO17 1BJ, United Kingdom
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12
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Mittal V, Mashanovich GZ, Wilkinson JS. Perspective on Thin Film Waveguides for on-Chip Mid-Infrared Spectroscopy of Liquid Biochemical Analytes. Anal Chem 2020; 92:10891-10901. [PMID: 32658466 DOI: 10.1021/acs.analchem.0c01296] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Miniaturized spectrometers offering low cost, low reagent consumption, high throughput, sensitivity and automation are the future of sensing and have significant applications in environmental monitoring, food safety, biotechnology, pharmaceuticals, and healthcare. Midinfrared (MIR) spectroscopy employing complementary metal oxide semiconductor (CMOS) compatible thin film waveguides and microfluidics shows great promise toward highly integrated and robust detection tools and liquid handling. This perspective provides an overview of the emergence of thin film optical waveguides used for evanescent field sensing of liquid chemical and biological samples for MIR absorption spectroscopy. The state of the art of new material and waveguide systems used for spectroscopic measurements in the MIR is presented. An outlook on the advantages and future of waveguide-based MIR spectroscopy for application in clinical settings for point-of-care biochemical analysis is discussed.
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Affiliation(s)
- Vinita Mittal
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Goran Z Mashanovich
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton, SO17 1BJ, United Kingdom.,School of Electrical Engineering, University of Belgrade, 11120 Belgrade, Serbia
| | - James S Wilkinson
- Zepler Institute for Photonics and Nanoelectronics, University of Southampton, Southampton, SO17 1BJ, United Kingdom
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13
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Gallacher K, Millar RW, Paul DJ, Frigerio J, Ballabio A, Isella G, Rusconi F, Biagioni P, Giliberti V, Sorgi A, Baldassarre L, Ortolani M. Characterization of integrated waveguides by atomic-force-microscopy-assisted mid-infrared imaging and spectroscopy. OPTICS EXPRESS 2020; 28:22186-22199. [PMID: 32752485 DOI: 10.1364/oe.393748] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/15/2020] [Indexed: 06/11/2023]
Abstract
A novel spectroscopy technique to enable the rapid characterization of discrete mid-infrared integrated photonic waveguides is demonstrated. The technique utilizes lithography patterned polymer blocks that absorb light strongly within the molecular fingerprint region. These act as integrated waveguide detectors when combined with an atomic force microscope that measures the photothermal expansion when infrared light is guided to the block. As a proof of concept, the technique is used to experimentally characterize propagation loss and grating coupler response of Ge-on-Si waveguides at wavelengths from 6 to 10 µm. In addition, when the microscope is operated in scanning mode at fixed wavelength, the guided mode exiting the output facet is imaged with a lateral resolution better than 500 nm i.e. below the diffraction limit. The characterization technique can be applied to any mid-infrared waveguide platform and can provide non-destructive in-situ testing of discrete waveguide components.
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14
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Ma Y, Dong B, Lee C. Progress of infrared guided-wave nanophotonic sensors and devices. NANO CONVERGENCE 2020; 7:12. [PMID: 32239361 PMCID: PMC7113365 DOI: 10.1186/s40580-020-00222-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/12/2020] [Indexed: 06/01/2023]
Abstract
Nanophotonics, manipulating light-matter interactions at the nanoscale, is an appealing technology for diversified biochemical and physical sensing applications. Guided-wave nanophotonics paves the way to miniaturize the sensors and realize on-chip integration of various photonic components, so as to realize chip-scale sensing systems for the future realization of the Internet of Things which requires the deployment of numerous sensor nodes. Starting from the popular CMOS-compatible silicon nanophotonics in the infrared, many infrared guided-wave nanophotonic sensors have been developed, showing the advantages of high sensitivity, low limit of detection, low crosstalk, strong detection multiplexing capability, immunity to electromagnetic interference, small footprint and low cost. In this review, we provide an overview of the recent progress of research on infrared guided-wave nanophotonic sensors. The sensor configurations, sensing mechanisms, sensing performances, performance improvement strategies, and system integrations are described. Future development directions are also proposed to overcome current technological obstacles toward industrialization.
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Affiliation(s)
- Yiming Ma
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117576 Singapore
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore, 117608 Singapore
- NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, 215123 China
| | - Bowei Dong
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117576 Singapore
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore, 117608 Singapore
- NUS Graduate School for Integrative Science and Engineering (NGS), National University of Singapore, Singapore, 117456 Singapore
| | - Chengkuo Lee
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117576 Singapore
- Center for Intelligent Sensors and MEMS (CISM), National University of Singapore, Singapore, 117608 Singapore
- NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, 215123 China
- NUS Graduate School for Integrative Science and Engineering (NGS), National University of Singapore, Singapore, 117456 Singapore
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Griskeviciute U, Millar RW, Gallacher K, Valente J, Paul DJ. Ge-on-Si waveguides for sensing in the molecular fingerprint regime. OPTICS EXPRESS 2020; 28:5749-5757. [PMID: 32121790 DOI: 10.1364/oe.382356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
Low loss, single mode, Ge-on-Si rib waveguides are used to demonstrated optical sensing in the molecular fingerprint region of the mid-infrared spectrum. Sensing is carried out using two spin-coated films, with strong absorption in the mid-infrared. These films are used to calibrate the modal overlap with an analyte, and therefore experimentally demonstrate the potential for Ge-on-Si waveguides for mid-infrared sensing applications. The results are compared to Fourier transform infrared spectroscopy measurements. The advantage of waveguide spectroscopy is demonstrated in terms of the increased optical interaction, and a new multi-path length approach is demonstrated to improve the dynamic range, which is not possible with conventional FTIR or attenuated total reflection (ATR) measurements. These results highlight the potential for Ge-on-Si as an integrated sensing platform for healthcare, pollution monitoring and defence applications.
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