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1.
Surg Clin North Am ; 100(6): 971-992, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33128891

RESUMO

Surgeons have been involved, since the beginning, in the development and evolution of endoscopy. They have been instrumental in developing new methods and have been actively involved in most of the therapeutic applications. The continued evolution of endoscopic technique is inevitable and will involve the integration of new technology with innovative thinking.


Assuntos
Endoscópios Gastrointestinais/história , Endoscopia Gastrointestinal/história , Tecnologia de Fibra Óptica/história , Endoscopia Gastrointestinal/instrumentação , Endoscopia Gastrointestinal/tendências , Europa (Continente) , Tecnologia de Fibra Óptica/instrumentação , História do Século XIX , História do Século XX , História Antiga , Humanos , Óptica e Fotônica/história , Óptica e Fotônica/tendências , Estados Unidos
3.
Sci Rep ; 10(1): 4545, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32161333

RESUMO

Laser microsurgery is a powerful tool for neurobiology, used to ablate cells and sever neurites in-vivo. We compare a relatively new laser source to two well-established designs. Rare-earth-doped mode-locked fibre lasers that produce high power pulses recently gained popularity for industrial uses. Such systems are manufactured to high standards of robustness and low maintenance requirements typical of solid-state lasers. We demonstrate that an Ytterbium-doped fibre femtosecond laser is comparable in precision to a Ti:Sapphire femtosecond laser (1-2 micrometres), but with added operational reliability. Due to the lower pulse energy required to ablate, it is more precise than a solid-state nanosecond laser. Due to reduced scattering of near infrared light, it can lesion deeper (more than 100 micrometres) in tissue. These advantages are not specific to the model system ablated for our demonstration, namely neurites in the nematode C. elegans, but are applicable to other systems and transparent tissue where a precise micron-resolution dissection is required.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Lasers de Estado Sólido , Microcirurgia/métodos , Neurônios/química , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/métodos , Itérbio/química , Óxido de Alumínio/química , Animais , Caenorhabditis elegans , Titânio/química
4.
Sensors (Basel) ; 20(4)2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32059555

RESUMO

A highly sensitive Au-graphene structure D-type fiber surface plasmon resonance biosensor is presented in this study to specifically detect biomolecules. The method of growing graphene is employed directly on the copper, and then a gold film of optimum thickness is sputtered, and the copper foil is etched to obtain the structure. This method makes the contact closer between the gold layer and the graphene layer to improve surface plasmon resonance performance. The performance of this type of surface plasmon resonance (SPR) sensor has been previously verified both theoretically and experimentally. With the proposed Au-graphene structure D-type fiber biosensor, the SPR behaviors are obtained and discussed. In the detection of ethanol solution, a red shift of 40 nm is found between the refractive index of 1.3330 and 1.3657. By calculation, the sensitivity of the sensor we designed is 1223 nm/RIU. Besides, the proposed sensor can detect the nucleotide bonding between the double-stranded DNA helix structures. Thus, our sensors can distinguish between mismatched DNA sequences.


Assuntos
Ouro/química , Grafite/química , Nanopartículas/química , Ressonância de Plasmônio de Superfície , DNA/análise , Tecnologia de Fibra Óptica/instrumentação , Análise Espectral Raman
5.
A A Pract ; 14(5): 134-136, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31876560

RESUMO

The choledochoscope is an additional tool to manage a difficult airway. We successfully used it for the first time for awake nasal intubation in a patient with no mouth opening resulting from bilateral temporomandibular ankylosis. The visual appearance of the airway structures was not compromised. However, the shorter length and larger diameter of the choledochoscope in comparison with the fiberoptic bronchoscope are crucial limiting factors of this method. We, therefore, suggest considering a choledochoscope for intubation in patients with difficult airway as a second-line alternative when a fiberoptic bronchoscope is not available.


Assuntos
Anquilose/cirurgia , Intubação Intratraqueal/instrumentação , Transtornos da Articulação Temporomandibular/cirurgia , Adolescente , Endoscopia/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Humanos , Masculino
6.
J Biomed Opt ; 24(12): 1-9, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31884746

RESUMO

Suturing of corneal incisions requires significant skill. We demonstrate a noncontact method that will simplify the bonding process. 5-mm-long penetrating vertical and slanted incisions were made in corneas of eyes, extracted from dead piglets. A fiber-optic laser system was used for laser soldering of the incisions, under close temperature control, using albumin solder. The burst-pressure PB immediately after the soldering was found to be PB ≈ 92 and 875 mmHg, for vertical and slanted incisions, respectively. PB = 875 mmHg is an exceptionally high figure, ≈10 times the clinically acceptable value for sutured incisions. Laser soldering was then performed on penetrating incisions made in the corneas of live healthy piglets, of weight ≈10 Kg. After a healing period, the eyes were extracted, and the corneas were examined by histopathology and by optical coherence tomography. Our method immediately generated watertight and strong bonding without noticeable corneal shape distortion. These results would be beneficial for cataract surgery and for corneal transplantations. The fiber-optic system makes it much easier to bond corneal incisions. In the future, laser soldering could be automated and efficiently used by less experienced surgeons, thereby reducing the workload on the experienced ones.


Assuntos
Córnea , Tecnologia de Fibra Óptica/instrumentação , Terapia a Laser/métodos , Animais , Córnea/fisiologia , Córnea/efeitos da radiação , Córnea/cirurgia , Terapia a Laser/instrumentação , Procedimentos Cirúrgicos sem Sutura , Suínos , Cicatrização
7.
Mikrochim Acta ; 186(11): 726, 2019 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-31655909

RESUMO

A reusable fiber optic chemiluminescent aptasensor (FOCA) is reported for the rapid and sensitive on-site detection of 17ß-estradiol (E2), an endocrine-disrupting compound frequently found in water samples. The E2-ovalbumin conjugate (E2-OVA) was covalently immobilized onto the optical fiber as a biorecognition element as well as a transducer. The affinity constant of the E2/aptamer complex was determined to be 1.35 × 106 M-1 using the FOCA. An indirect competitive assay was then developed for E2 detection. A certain concentration of HRP-E2 aptamers pre-reacted with samples containing E2 in various concentrations. Part of HRP-E2 aptamers specially bound to the sensor surface after introduction of the mixture. This catalyzed the chemiluminescece reaction of a chemiluminescent system composed of luminol and H2O2. A higher concentration of E2 led to less HRP-E2 aptamer bound to the biosensor surface, thus resulting in less chemiluminescence. Highly sensitive detection of E2 was achieved under optimal conditions, and the limit of detection is 48 ng ·L-1 (0.18 nM). The whole analytical process, including measurement and regeneration, can be performed in <15 min. The robustness of the biosensor allows its application to multiple assays with little activity loss. The selectivity, recovery, and accuracy of the sensor was demonstrated by evaluating its response to potentially interfering endocrine disruptors in spiked water samples. Graphical abstract Schematic diagram of the fiber optic chemiluminescent aptasensor system (A), detection mechanism of 17ß-estradiol (B), and its application for detection of 17ß-estradiol with rapidity and sensitivity (C and D).


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Disruptores Endócrinos/análise , Estradiol/análise , Poluentes Químicos da Água/análise , Sequência de Bases , Técnicas Biossensoriais/instrumentação , Água Potável/análise , Tecnologia de Fibra Óptica/instrumentação , Peróxido de Hidrogênio/química , Proteínas Imobilizadas/química , Limite de Detecção , Luminol/química , Ovalbumina/química , Águas Residuárias/análise
8.
Biosens Bioelectron ; 146: 111760, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31605987

RESUMO

A novel optical fiber glucose biosensor based on fluorescent carbon quantum dots (CQDs)-glucose oxidase (GOD)/cellulose acetate (CA) complex sensitive film was fabricated, in which the dip-coating method was adopted to immobilize the CQDs-GOD/CA complex sensitive film onto the end face of the optical fiber. The surface morphology, microstructure and optical performances of the sensitive film were characterized by field emission scanning electron microscope (FESEM), atomic force microscope (AFM), Zeiss Axiovert 25 inverted microscope, Fourier transform infrared spectroscopy (FTIR), Ultraviolet-visible spectrophotometer and fluorescence spectrophotometer, respectively. The developed fiber-optic biosensor exhibits high sensitivity and repeatability for continuous online detection of low concentration glucose, allowing visualization of real-time glucose fluctuations over a period of time. The change ratios in fluorescence intensity of the biosensor are linear with glucose concentration in various ranges including micromole and nanomole levels, and the relationship between relative fluorescence intensity ratio and glucose concentration complies well with the modified Stern-Volmer equation in the range of 10-200 µmol/L with the detection limit of 6.43 µM, and in the range of 10-100 nmol/L with the detection limit of 25.79 nM, respectively.


Assuntos
Técnicas Biossensoriais/instrumentação , Glicemia/análise , Celulose/análogos & derivados , Glucose Oxidase/química , Fibras Ópticas , Carbono/química , Celulose/química , Desenho de Equipamento , Tecnologia de Fibra Óptica/instrumentação , Fluorescência , Humanos , Limite de Detecção , Pontos Quânticos/química
9.
Photosynth Res ; 142(3): 283-305, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31541418

RESUMO

Regulated heat dissipation under excessive light comprises a complexity of mechanisms, whereby the supramolecular light-harvesting pigment-protein complex (LHC) shifts state from light harvesting towards heat dissipation, quenching the excess of photo-induced excitation energy in a non-photochemical way. Based on whole-leaf spectroscopy measuring upward and downward spectral radiance fluxes, we studied spectrally contiguous (hyperspectral) transient time series of absorbance A(λ,t) and passively induced chlorophyll fluorescence F(λ,t) dynamics of intact leaves in the visible and near-infrared wavelengths (VIS-NIR, 400-800 nm) after sudden strong natural-like illumination exposure. Besides light avoidance mechanism, we observed on absorbance signatures, calculated from simultaneous reflectance R(λ,t) and transmittance T(λ,t) measurements as A(λ,t) = 1 - R(λ,t) - T(λ,t), major dynamic events with specific onsets and kinetical behaviour. A consistent well-known fast carotenoid absorbance feature (500-570 nm) appears within the first seconds to minutes, seen from both the reflected (backscattered) and transmitted (forward scattered) radiance differences. Simultaneous fast Chl features are observed, either as an increased or decreased scattering behaviour during quick light adjustment consistent with re-organizations of the membrane. The carotenoid absorbance feature shows up simultaneously with a major F decrease and corresponds to the xanthophyll conversion, as quick response to the proton gradient build-up. After xanthophyll conversion (t = 3 min), a kinetically slower but major and smooth absorbance increase was occasionally observed from the transmitted radiance measurements as wide peaks in the green (~ 550 nm) and the near-infrared (~ 750 nm) wavelengths, involving no further F quenching. Surprisingly, in relation to the response to high light, this broad and consistent VIS-NIR feature indicates a slowly induced absorbance increase with a sigmoid kinetical behaviour. In analogy to sub-leaf-level observations, we suggest that this mechanism can be explained by a structure-induced low-energy-shifted energy redistribution involving both Car and Chl. These findings might pave the way towards a further non-invasive spectral investigation of antenna conformations and their relations with energy quenching at the intact leaf level, which is, in combination with F measurements, of a high importance for assessing plant photosynthesis in vivo and in addition from remote observations.


Assuntos
Folhas de Planta/química , Folhas de Planta/fisiologia , Carotenoides/química , Clorofila/química , Desenho de Equipamento , Tecnologia de Fibra Óptica/instrumentação , Tecnologia de Fibra Óptica/métodos , Fluorescência , Juglans/química , Luz , Morus/química , Morus/fisiologia , Processos Fotoquímicos , Pigmentos Biológicos/química , Espectroscopia de Luz Próxima ao Infravermelho
10.
Anal Bioanal Chem ; 411(26): 6813-6823, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432237

RESUMO

We demonstrate a DNA-based optical fiber device that uses an in-fiber grating, a light absorbing coating with surface anchored DNA, and a built-in optical thermometer. This device is used for precisely thermal cycling surface DNA spots bound by a simple UV cross-linking technique. Near-infrared light of wavelengths near 1550 nm and guided power near 300 mW is coupled out of the fiber core by a tilted fiber Bragg grating inscribed in the fiber and absorbed by the coating to increase its temperature to more than 95 °C. A co-propagating broadband light signal (also in the near-infrared region) is used to measure the reflection spectrum of the grating and thus the temperature from the wavelength shifts of the reflection peaks. The device is capable of sensitive DNA melt analysis and can be used for DNA amplification. Graphical abstract.


Assuntos
Técnicas Biossensoriais/instrumentação , DNA/química , Tecnologia de Fibra Óptica/instrumentação , Hibridização de Ácido Nucleico , DNA/genética , Desenho de Equipamento , Calefação , Ácidos Nucleicos Imobilizados/química , Ácidos Nucleicos Imobilizados/genética , Desnaturação de Ácido Nucleico , Fibras Ópticas
11.
Biosens Bioelectron ; 142: 111505, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357154

RESUMO

Surface plasmon resonance (SPR) technology has effectively bolstered optic fiber sensing in fields of life science, clinical diagnosis, medicine, food safety and so on. The current review outlines the research status of fiber optic biosensor based on SPR, and the merits of optical fiber sensor and the development of optical fiber sensor based on SPR are completely covered. An in-depth review of four devices for generating SPR is presented, and optical fiber is finally adopted for a substrate to generate SPR. Different prototypes of optical fiber biosensor based on SPR are meticulously outlined: optical fiber grating biosensor based on SPR and optical fiber structured type biosensor based on SPR, and representative instances from literature are presented to verify the latest advancements in this potentially valuable research avenue. In addition, the sensing performance of different optical fiber structured type biosensor based on SPR are compared. What's more, simultaneous multi-parameter detection and improvement of sensitivity are discussed and summarized. The article concludes identify key challenges and develop orientation of optical fiber biosensor based on SPR.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Animais , Desenho de Equipamento , Tecnologia de Fibra Óptica/métodos , Humanos , Fibras Ópticas , Ressonância de Plasmônio de Superfície/métodos
12.
Sensors (Basel) ; 19(13)2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31284380

RESUMO

In this paper, we report the development of a portable energy-efficient interrogator (Perrogator) for wavelength-based optical sensors. The interrogator is based on a compact solution encompassing a white light source and the spectral convolution between the sensor and a tunable filter, which is acquired by a photodetector, where a microcontroller has two functions: (i) To control the filter tuning and to (ii) acquire the photodetector signal. Then, the data is sent to a single-board computer for further signal processing. Furthermore, the employed single-board computer has a Wi-Fi module, which can be used to send the sensors data to the cloud. The proposed approach resulted in an interrogator with a resolution as high as 3.82 pm (for 15.64 nm sweeping range) and maximum acquisition frequency of about 210 Hz (with lower resolution ~15.30 pm). Perrogator was compared with a commercial fiber Bragg grating (FBG) interrogator for strain measurements and good agreement between both devices was found (1.226 pm/µÎµ for the commercial interrogator and 1.201 pm/µÎµ for the proposed approach with root mean square error of 0.0144 and 0.0153, respectively), where the Perrogator has the additional advantages of lower cost, higher portability and lower energy consumption. In order to demonstrate such advantages in conjunction with the high acquisition frequency allowed us to demonstrate two wearable applications using the proposed interrogation device over FBG and Fabry-Perot interferometer (FPI) sensors. In the first application, an FBG-embedded smart textile for knee angle assessment was used to analyze the gait of a healthy person. Due to the capability of reconstructing the FBG spectra, it was possible to employ a technique based on the FBG wavelength shift and reflectivity to decouple the effects of the bending angle and axial strain on the FBG response. The measurement of the knee angle as well as the estimation of the angular and axial displacements on the grating that can be correlated to the variations of the knee center of rotation were performed. In the second application, a FPI was embedded in a chest band for simultaneous measurement of breath and heart rates, where good agreement (error below 5%) was found with the reference sensors in all analyzed cases.


Assuntos
Marcha/fisiologia , Determinação da Frequência Cardíaca/instrumentação , Articulação do Joelho/fisiologia , Processamento de Sinais Assistido por Computador , Dispositivos Eletrônicos Vestíveis , Desenho de Equipamento , Tecnologia de Fibra Óptica/instrumentação , Frequência Cardíaca/fisiologia , Determinação da Frequência Cardíaca/métodos , Humanos , Interferometria/instrumentação , Respiração , Tecnologia sem Fio/instrumentação
13.
Sensors (Basel) ; 19(14)2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31336770

RESUMO

In order to improve the precision and stability of puncture surgical operations to assist doctors in completing fine manipulation, a new of type puncturing needle sensor is proposed based on a fiber Bragg grating (FBG). Compared with the traditional puncture needle sensor, the new type of puncturing needle sensor is able to sense not only the axial force, but also the torque force during the puncture process. A spoke-type structure is designed near the needle tip. In order to eliminate the influence of temperature and realize temperature compensation, a reference fiber method using three FBGs is applied. FBG1 and the reference FBG2 are pasted on the upper and lower surfaces of the new-type elastic beam, and FBG3 is pasted into the groove on the surface of the new type of puncturing needle cylinder. The difference of Bragg wavelength between FBG1 and the reference FBG2 is calibrated with the torque force, while the difference between the Bragg wavelength of the FBG3 and the reference FBG2 is calibrated with the axial force. Through simulation and sensing tests, when the torque force calibration range is 10 mN·m, the torque average sensitivity is 22.8 pm/mN·m, and the determination coefficient R2 is 0.99992, with a hysteresis error YH and repetition error YR of 0.03%FS and 0.81%FS, respectively. When the axial force calibration rang is 5 N, the axial force average sensitivity is 0.089 nm/N, and the determination coefficient R2 is 0.9997, with hysteresis error YH and repetition error YR of 0.014%FS and 0.11%FS, respectively. The axial force resolution and torque resolution of the new type of puncturing needle sensor are 0.03 N and 0.8 mN·m, respectively. The experimental data and simulation analysis show that the proposed new type of puncturing needle sensor has good practicability and versatility.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Punções/instrumentação , Calibragem , Desenho de Equipamento , Tecnologia de Fibra Óptica/métodos , Análise de Elementos Finitos , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Agulhas , Torque
14.
Respir Investig ; 57(5): 481-489, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31353288

RESUMO

BACKGROUND: Peripheral pulmonary lesions are rarely observed directly before transbronchial biopsy. This study aimed to characterize the differences between malignant and benign peripheral pulmonary lesions according to the findings of direct observation using probe-based optical fiberscopy. METHODS: Thirty patients who underwent probe-based optical fiberscopy in combination with bronchoscopy using endobronchial ultrasonography with a guide sheath for the evaluation of peripheral pulmonary lesions were prospectively included in this study. The patients were divided into the malignant and benign groups according to their final diagnosis. The findings of probe-based optical fiberscopy in the two groups were compared. RESULTS: The numbers of patients who were diagnosed using histological or bacteriological analyses via bronchoscopic sampling in the malignant and benign groups were 20/23 (87.0%) and 2/7 (28.6%), respectively. On probe-based optical fiberscopy, angiogenesis and vascular engorgement were observed only in the malignant group. The disappearance of subepithelial microvessel transparency and presence of bronchiolar stenosis were observed more frequently in the malignant group (78.3% and 60.9%) than in the benign group (28.6% and 28.6%), whereas increased mucus secretion was observed more frequently in the benign group (71.4%) than in the malignant group (8.7%). CONCLUSIONS: These results suggest that the findings of direct observation using probe-based optical fiberscopy are useful for differentiating malignant from benign peripheral pulmonary lesions. TRIAL REGISTRY: UMIN-CTR; UMIN000018796; URL: https://www.umin.ac.jp/ctr/index.htm.


Assuntos
Endossonografia/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Pulmão/patologia , Fibras Ópticas , Idoso , Idoso de 80 Anos ou mais , Brônquios/patologia , Broncoscopia , Constrição Patológica , Endossonografia/métodos , Feminino , Tecnologia de Fibra Óptica/métodos , Humanos , Pulmão/irrigação sanguínea , Pneumopatias/metabolismo , Pneumopatias/patologia , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Muco/metabolismo , Neovascularização Patológica/patologia , Estudos Prospectivos
15.
Biosens Bioelectron ; 140: 111350, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31154255

RESUMO

Herein, a home-build fiber optic surface plasmon resonance (FO-SPR) biosensing platform has been developed for highly sensitive detection of platelet-derived growth factor (PDGF-BB) based aptamer-functionalized AuNPs for signal enhancement. In this biosensor, the PDGF-BB aptamer was used to specifically capture PDGF-BB, and the antifouling peptide demonstrated great ability for resisting non-specific adsorption. After a sandwich reaction, the aptamer, PDGF-BB and aptamer-functionalized AuNPs complexes were formed on the fiber optic (FO) probe surface to significantly amplify FO-SPR signal. This method exhibited a broad detection range from 1 to 1000 pM of PDGF-BB and a low detection limit of 0.35 pM. Moreover, this biosensor was successfully applied to the detection of PDGF-BB in 10% human serum samples without suffering from serious interference owing to the excellent antifouling property of the peptide. Thus, this developed FO-SPR biosensor could be a potential alternative device for proteins determination, even as a point-of-care diagnostic tool (POCT) in clinical application.


Assuntos
Aptâmeros de Nucleotídeos/química , Becaplermina/sangue , Ressonância de Plasmônio de Superfície/instrumentação , Incrustação Biológica , Desenho de Equipamento , Tecnologia de Fibra Óptica/instrumentação , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Peptídeos/química
16.
Phys Med Biol ; 64(12): 125015, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31117059

RESUMO

We present a novel FMT endoscope by using a MEMS scanning mirror and an optical fiberscope. The diameter of this highly miniaturized FMT device is only 5 mm. To our knowledge, this is the smallest FMT device we found so far. Several phantom experiments based on indocyanine green (ICG) were conducted to demonstrate the imaging ability of this device. Two tumor-bearing mice were systematically injected with tumor-targeted NIR fluorescent probes (ATF-PEG-IO-830) and were then imaged to further demonstrate the ability of this FMT endoscope for imaging small animals.


Assuntos
Endoscopia/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Fluorescência , Sistemas Microeletromecânicos/instrumentação , Miniaturização/métodos , Imagens de Fantasmas , Tomografia/instrumentação , Animais , Corantes Fluorescentes , Verde de Indocianina , Camundongos
17.
Rev Sci Instrum ; 90(4): 043110, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31043005

RESUMO

Raman spectroscopy has proven to be an effective tool for molecular analysis in different applications. In clinical diagnostics, its application has enabled nondestructive investigation of biological tissues and liquids. The human perilymph, for example, is an inner ear liquid, essential for the hearing sensation. The composition of this liquid is correlated with pathophysiological parameters and was analyzed by extraction and mass spectrometry so far. In this work, we present a fiber optic probe setup for the Raman spectroscopic sampling of inner ear proteins in solution. Multivariate data analysis is applied for the discrimination of individual proteins (heat shock proteins) linked to a specific type of hearing impairment. This proof-of-principle is a first step toward a system for sensitive and continuous in vivo perilymph investigation in the future.


Assuntos
Tecnologia de Fibra Óptica/métodos , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Perilinfa/metabolismo , Análise Espectral Raman/instrumentação , Análise Espectral Raman/métodos , Algoritmos , Aspirina/química , Calibragem , Desenho de Equipamento , Escherichia coli , Tecnologia de Fibra Óptica/instrumentação , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP90/química , Humanos , Análise dos Mínimos Quadrados , Análise Multivariada , Perilinfa/química , Análise de Componente Principal , Prolina/química , Estudo de Prova de Conceito , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Análise de Regressão , Processamento de Sinais Assistido por Computador
18.
Nat Methods ; 16(6): 553-560, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31086339

RESUMO

Animal behavior originates from neuronal activity distributed across brain-wide networks. However, techniques available to assess large-scale neural dynamics in behaving animals remain limited. Here we present compact, chronically implantable, high-density arrays of optical fibers that enable multi-fiber photometry and optogenetic perturbations across many regions in the mammalian brain. In mice engaged in a texture discrimination task, we achieved simultaneous photometric calcium recordings from networks of 12-48 brain regions, including striatal, thalamic, hippocampal and cortical areas. Furthermore, we optically perturbed subsets of regions in VGAT-ChR2 mice by targeting specific fiber channels with a spatial light modulator. Perturbation of ventral thalamic nuclei caused distributed network modulation and behavioral deficits. Finally, we demonstrate multi-fiber photometry in freely moving animals, including simultaneous recordings from two mice during social interaction. High-density multi-fiber arrays are versatile tools for the investigation of large-scale brain dynamics during behavior.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Tecnologia de Fibra Óptica/métodos , Neurônios/fisiologia , Optogenética , Fotometria/métodos , Proteínas Vesiculares de Transporte de Aminoácidos Inibidores/fisiologia , Animais , Comportamento Animal , Encéfalo/citologia , Sinalização do Cálcio , Tecnologia de Fibra Óptica/instrumentação , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/citologia
19.
Adv Mater ; 31(23): e1807552, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30985020

RESUMO

A colorimetric multifunctional phototransmittance-based structural durability monitoring system is developed. The system consists of an array with four indium gallium zinc oxide (IGZO)-based phototransistors, a light source at a wavelength of 405 nm through a side-emitting optical fiber, and pH- and Cl-selective color-variable membranes. Under illumination at the wavelength of 405 nm at corrosion status, the pH- and Cl-responsive membrane, showing a change in their color, generates a change in the intensity of the transmitted light, which is received by the phototransistor array in the form of an electrical current. Ids and R (Ids /IpH 12 ) are inversely proportional to the pH, which ranges from 10 to 12. When the pH drops from 12 to 10, the magnitude of Ids and R increases to ≈103 . In the case of Cl detection, Ids and R (Ids /ICl 0 wt% ) increase nearly 50 times with an increase in Cl concentration of 0.05 wt%, and when the Cl concentration reaches 0.30 wt%, Ids and R increase to ≈103 times greater. This multifunctional colorimetric durability sensing system demonstrates considerable potential as a novel smart-diagnostic tool of structural durability with high stability, high sensitivity, and multifunction.


Assuntos
Colorimetria/métodos , Materiais de Construção/análise , Cloretos/análise , Colorimetria/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Tecnologia de Fibra Óptica/métodos , Gálio/química , Concentração de Íons de Hidrogênio , Índio/química , Luz , Membranas Artificiais , Fibras Ópticas , Óxido de Zinco/química
20.
Biosens Bioelectron ; 132: 368-374, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30901726

RESUMO

A simple, convenient, and inexpensive method to fabricate optical fiber based biosensors which utilize periodic hole arrays in gold films for signal transduction is reported. The process of hole array formation mainly relies on self-assembly of hydrogel microgels in combination with chemical gold film deposition and subsequent transfer of the perforated film onto an optical fiber tip. In the fabrication process solely chemical wet lab techniques are used, avoiding cost-intensive instrumentation or clean room facilities. The presented method for preparing fiber optic plasmonic sensors provides high throughput and is perfectly suited for commercialization using batch processing. The transfer of the perforated gold film onto an optical fiber tip does not affect the sensitivity of the biosensor ((420 ±â€¯83) nm/refractive index unit (RIU)), which is comparable to sensitivities of sensor platforms based on periodic hole arrays in gold films prepared by significantly more complex methods. Furthermore, real-time and in-line immunoassay studies with a specially designed 3D printed flow cell are presented exploiting the presented optical fiber based biosensors.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Imunoensaio/instrumentação , Imunoglobulina G/análise , Ressonância de Plasmônio de Superfície/instrumentação , Animais , Desenho de Equipamento , Cabras , Ouro/química , Fibras Ópticas , Impressão Tridimensional , Coelhos , Refratometria/instrumentação
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