The intention of the present invention is to provide an optical waveguide type glucose sensor which enables highly sensitive and highly accurate analysis of extremely small amounts of glucose contained in a body fluid, for example, extracted from an analyte, a device for optical waveguide type glucose measurement by use of the optical waveguide type glucose sensor, a system for the optical waveguide type glucose measurement and a methodology for the optical waveguide type glucose measurement. A light such as a laser light is made incident to an optical waveguide layer via a grating. The analyte is defined as a dielectric material and its index is set to 1.33. Glucose-Sensitive Hydrogel Optical Fibers Functionalized with Phenylboronic Acid. Ultrasensitive mechanical crack-based sensor inspired by the spider sensory system. In more advanced sensors, the measurement of phase difference allows very accurate measurement of small pressure changes. Therefore, hydrogels with optimized optical and mechanical properties are favorable materials for light-guiding in tissues. Copyright 2018, Wiley; (e,f) Stretchable sensory fiber integrated with an LED and a photodiode to track the knee angle. The stretchable sensor was attached to an elastic kneepad and applied for sports activities monitoring (Figure 7b,c). Front. Reproduced with permission [86]. The invention relates to a optical trap, chip and sensor system comprising the . an optical waveguide sensor for determining an analyte in a medium, which sensor comprises an optical waveguide having a portion to be brought into contact with said medium, said portion having a plurality of cells arranged in an array which substantially covers the cross-sectional area of the waveguide, each of said cells containing an indicator Sensing functionalities of the waveguide can be further expanded by the exploration of novel structures, materials, and principles to provide comprehensive information inside the body for diagnostics and health tracking. Prajzler et al. Copyright 2017, Elsevier. Lett. The functionality is limited to basic scrolling. Choi M., Choi J.W., Kim S., Nizamoglu S., Hahn S.K., Yun S.H. Leal-Junior AG, Diaz CAR, Avellar LM, Pontes MJ, Marques C et al. Reproduced with permission [40]. The flexible microfiber resonator was worn on the human wrist to detect artery pulse, which is an important indicator of heartbeat and arterial blood pressure (Figure 7e,f). When a waveguide is derived from a stretchable material, the team working on this project was thus able to produce elastomeric optical waveguides that can deform with great ease. Multiplexing capabilities of the FBG-based sensors have been explored by using a free-running fiber laser based on dual-comb spectroscopy. Optical and mechanical characterizations of the resins (photocurable and PDMS resins). The large water content and porous structures of hydrogels enable encapsulating living cells and functional molecules for innovative biosensing applications such as continuous glucose monitoring, metal-ion detection, and in vivo toxicity sensing. Additionally, the sensory fibers could also be used to track the evolution of the knee angle during walking or running, enabling applications in the assessment of athletic performance, knee rehabilitation, and assisting human/robot walking (Figure 8e,f) [68]. Chang-Yen D.A., Eich R.K., Gale B.K. The transmission loss of the cellulose optical fiber was ~1 dB/cm. Leber et al. Copyright 2019, Wiley; (b,c) Stretchable FBG sensor installed on an elastic kneepad to monitor various knee-related sports activities. Notice. Tan HW, Zhou YF, Tao QZ, Rosen J, van Dijken S. Bioinspired multisensory neural network with crossmodal integration and recognition. The vertical structure increases the sensing area and can be fabricated in a one-step lithography step enabling easy and high-resolution fabrication and making this waveguide attractive in . The loss in the polymeric materials mainly arise from absorption of the constituent molecules and light scattering due to the structural imperfections. In the following sections, the waveguides made from polymeric materials including hydrogels, biodegradable polymers, and elastomers will be further detailed and discussed. 2125 June 2009; pp. The active optical waveguide refers to the optical output from the intrinsic emission of the sample by exciting it with an external energy source, whereas the passive optical waveguide mode refers to the light propagation of optical source [ 21, 22, 23, 24, 25 ]. We tested the sensors performance by monitoring the adhesion of Escherichia coli K12 cells to the sensor surface. AI 8:773166. doi: 10.3389/frobt.2021.773166 Ma LY, Wu RH, Patil A, Zhu SH, Meng ZH et al. Reproduced with permission [64]. Guo J., Niu M., Yang C. Highly flexible and stretchable optical strain sensing for human motion detection. However, in the conventional glucose sensor there have been problems, such as, since the optical waveguide layer is made up with a single layer, there is a limit to the sensitivity in detecting the change in the quantity of the evanescent wave generated in the optical waveguide layer, and also the film structure on the optical waveguide layer is not suitable for analysis of the extremely small amounts of biomolecules contained in blood and the like which are extracted from the analyte. Li et al. Yamada T., Hayamizu Y., Yamamoto Y., Yomogida Y., Izadi-Najafabadi A., Futaba D.N., Hata K. A stretchable carbon nanotube strain sensor for human-motion detection. Copyright 2015, Optical Society of America; (b) Cross-section images of step-index, core-cladding PDMS optical fibers. For example, an intensity-modulated microbend fiber-optic sensor has been developed for noninvasive monitoring of respiratory in strong electromagnetic interference environments during magnetic resonance imaging (MRI) [80]. . The waveguide design results in increased depth of penetration into the sample volume, which makes it suitable for detecting micrometer-sized biological objects. Forster T., Strohhofer C., Bock K., Kasak P., Danko M., Kronekova Z., Nedelcev T., Krupa I., Lacik I. Biosensor for calcium based on a hydrogel optical waveguide with integrated sensor proteins; Proceedings of the TRANSDUCERS 2009-2009 International Solid-State Sensors, Actuators and Microsystems Conference; Denver, CO, USA. Guo J., Liu X., Jiang N., Yetisen A.K., Yuk H., Yang C., Khademhosseini A., Zhao X., Yun S.H. Continuous monitoring of glucose levels in the blood is of great significance for management and treatment of diabetes mellitus in clinics. Keywords: tactile sensor, minimally invasive surgical, 3D surface, optical sensor, multi-point force measurement. To minimize the analyte-independent effects, hydrogel waveguides doped with two types of QDs at different emission bands were demonstrated for ratiometric sensing of metal ions (Figure 5e) [76]. The recent advances in nanotechnology have created the need for the development of materials and devices with unique properties, suitable for applications in related areas such as nano-electronics, Recent development of optical gas sensing devices are reviewed. Besides, there have also been efforts in developing optical waveguides that are biodegradable. Generating an ePub file may take a long time, please be patient. P2001-358333, filed on Nov. 22, 2001, No. Analogously, optical waveguide has a longer interacting distance while microcavities focus on the confinement of light. A low-cost integrated biosensing platform based on SiN nanophotonics for biomarker detection in urine. Figure 1e shows the microscope images of the core-cladding hydrogel fibers with different sizes. or First, a OWG sensor based on THPP was prepared using the spin-coating method. We have reviewed recent progress on soft and stretchable polymeric optical waveguides for wearable and biomedical sensing applications. 1) a layer having a structure in which the enzyme and the coloring dyestuff are fixed by cross linking polymers. germanium refractive index germanium refractive index. Polymer optical fiber sensors in healthcare applications: a comprehensive review. Skin-inspired highly stretchable and conformable matrix networks for multifunctional sensing. A stretchable fiber-optic strain sensor made up of a sinuous-shaped fiber-Bragg-grating (FBG) embedded in a slab PDMS substrate has been fabricated by using 3D-printed mold [84]. Except for light transmission, waveguides can also be designed and functionalized for highly sensitive sensing (e.g., strain, temperature, and bioanalytes), through the modulation of light intensity, phase, wavelength, or polarization [28,29,30,31]. In recent work, researchers developed a carbon dots (CDs)-doped slab hydrogel waveguide for Hg2+ sensing (Figure 5c) [75]. 58985903. . Reproduced with permission [83]. Despite the many existing reviews focusing on the materials that these devices are made from, a systematic review that relates these devices to the various materials, fabrication . With a molecular weight of 10 kDa and a concentration of 10% w/v, PEGDA hydrogels showed notable transparency with an average loss as low as 0.17 dB/cm in the wavelength range of 450550 nm. P2002-140055, filed on May 15, 2002; the entire contents of which are incorporated herein by reference. and Niels B. Larsen2, 1Optics and Fluid Dynamics Department, Ris National Laboratory, DK-4000 Roskilde, Denmark, 2Danish Polymer Center, Ris National Laboratory, DK-4000 Roskilde, Denmark, Corresponding author: henrik.pedersen@risoe.dk, Your library or personal account may give you access. Amjadi M., Yoon Y.J., Park I. Ultra-stretchable and skin-mountable strain sensors using carbon nanotubesEcoflex nanocomposites. A linear sensing range of 2070 C was achieved by ratiometric measurements of the dual-wavelength UCNPs emissions upon near-infrared (NIR) excitation. P2002-7807, filed on Jan. 16, 2002, No. Cost-effective multimode polymer waveguides for high-speed on-board optical interconnects. Method and device for measuring luminescence, Multiple-mode planar-waveguide sensor, fabrication materials and techniques, Fluorescent indicator for measuring the activity of alkali metal ions in sample solutions, Optical waveguide type glucose sensor and optical waveguide type glucose sensor measuring method, Optical waveguide type immunosensor and optical waveguide type immunoassay method, Antigen measurement apparatus and method, pallet, and antibody chip package, Optical waveguide glucose sensor and coloring reagent film fixing method, Optical waveguide type glucose sensor and method of immobilizing coloring reagent, Bio measurement device and bio apparatus having the bio measurement device, Optical waveguide type glucose sensor and coloring reagent membrane immobilizing method, Lapse for failure to pay maintenance fees, Information on status: patent discontinuation, Lapsed due to failure to pay maintenance fee. blood, urine; Haemocytometers, Chemical analysis of biological material, e.g. This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. A light-emitting diode and a photodiode were embedded at each end of the waveguide, serving as the light source and detector, respectively. Mar 2014 - Sep 20162 years 7 months. The directions of the orientation planes (roll, pitch, and yaw) are also shown. Moreover, the high rigidity of silica fibers poses a limit for many applications such as human motion detection, where large deformation needs to be accommodated by the sensor. Free format text: But the single crystals cannot transport the multi-waveguide mode [ 26 ]. For waveguides with a square cross-section of 1 m2, a 5 m gap between them and a 785 nm operation wavelength, we perform finite-difference time-domain simulations of the beam profiles and the trapping forces acting on polystyrene beads (diameter 0.2-1.4 m). Reproduced with permission [85]. Copyright 2018, Optical Society of America; (i) Surface-enhanced Raman scattering (SERS) spectra of R6G molecules at various concentrations measured by AgNPs-doped hydrogel optical fiber. This intermediate layer comprises a material that is doped with a sensor material to respond to an analyte of interest by luminescing or by developing optical absorption in the transmission region of the core fiber and that has a refractive index greater than the . fabricated slab and biocompatible optical waveguide from polyethylene glycol diacrylate (PEGDA) hydrogels by mold injection and ultraviolet (UV)-induced polymerization processes (Figure 1a,b) [36]. Peters K. Polymer optical fiber sensors-a review. Vaddiraju S., Burgess D.J., Tomazos I., Jain F.C., Papadimitrakopoulos F. Technologies for continuous glucose monitoring: Current problems and future promises. The sewn fibers were installed on a piece of athletic tape for wearable monitoring of strains generated by weight-bearing activities, which could be used in sports monitoring and functional fitness tests (Figure 6a,b). Keywords According to a ninth aspect of the present invention, a method for glucose measurement comprises contacting an upper portion of an electro-conductive body formed on a substrate and connected to a cathode of an electric source with a first portion of an analyte, contacting an electrode plate connected to an anode of the electric source with a second portion of the analyte, generating an electric field between the electro-conductive body and the electrode plate, extracting a body fluid containing glucose from the analyte towards the electro-conductive body, causing a coloring reaction by the glucose on the substrate, irradiating a light from beneath one side of the substrate maintaining a predetermined incident angle, absorbing the light by the coloring reaction within a second optical waveguide layer on the first optical waveguide layer formed on a surface of the substrate, the second optical waveguide layer having a refractive index higher than that of the first optical waveguide layer and measuring the quantity of an emitted light below the other side of the substrate. Zhao et al. Such devices have been designed with various functionalities for wearable/implantable monitoring of physiological (e.g., heart rate, body temperature) [3,4,5,6,7,8,9,10,11], mechanical (e.g., pressure, strain, torsion) [12,13,14,15,16,17,18,19,20,21], and biochemical (e.g., glucose, sweat, blood oxygen saturation) conditions [22,23,24,25,26] of the human body. However, these sensors normally require complex manufacturing processes and have poor biocompatibility due to the usage of electrically conductive components. To address this problem, many researchers developed waveguides from organic elastomers. 1a. Odeh M., Voort B., Anjum A., Paredes B., Dimas C., Dahlem M.S. Optics letters. We are experimenting with display styles that make it easier to read articles in PMC. used to detect optical phase shift of the guided compact and rugged compared with the fiber-optic such optical waveguide sensors are more compact and rugged compared with the Soft and Stretchable Polymeric Optical Waveguide-Based Sensors for Wearable and Biomedical Applications. 61805126). However, due to their poor biocompatibility, long-term implantation of these fibers could induce severe inflammation and immune reactions. 28 September2 October 2015; pp. Jolliffe IT, Cadima J. The core of the waveguide was a silk film with a high RI of 1.54; while the cladding was a silk hydrogel, having a low RI of ~1.34. Reproduced with permission [73]. The sensor system for the detection of chemical substances has a spiral optical waveguide which produces an evanescent field penetrating into the adjacent medium, a light source for coupling light into the waveguide, and a detecting circuit for receiving light from the waveguide and producing an output signal reflecting the sensed chemical substance. The sensor structure is bioinspired in orb webs, which are multifunctional devices for prey capturing and vibration transmission. For wearable and skin-comfortable sensing, sensors with high flexibility and deformability are demanded to ensure high mechanical compliance with the soft and curvilinear surfaces of the human body. Single-shot on-chip spectral sensors based on photonic crystal slabs. To optimize the material loss, approaches such as filtration, degassing and compositional adjustments (e.g., crosslinking density and molecular weight) may be adopted [32,34,36]. However, these sensors are often in need of complex production processes and are susceptible to EMI and electrical safety issues (e.g., current leakage). The basic objective of an optical biosensor is to produce a signal which is proportionate to the concentration of a measured substance (analyte). Rugged and breathable forms of stretchable electronics with adherent composite substrates for transcutaneous monitoring. Liu Z., Zhang Z.F., Tam H.Y., Tao X. Multifunctional smart optical fibers: Materials, fabrication, and sensing applications. 10/302,685, filed Nov. 22, 2002, now U.S. Pat. The core and cladding were made of polystyrene-based polymer Star Clear 1044 (RI, 1.52) and fluorinated polymer Daikin T-530 (RI, 1.36), respectively. Reproduced with permission [34]. Spin-coating techniques have also been used to deposit silk planar waveguides on borosilicate glasses and Si/SiO2 substrates, which showed optical losses of 0.22 dB/cm at 632.8 nm [43]. A monolithic PDMS waveguide system fabricated using soft-lithography techniques. Author Information. By virtue of the ratiometric readout, the temperature sensor was self-calibrated and its sensing performance was independent of strain deformations. reported scalable fabrications of highly stretchable, core-cladding optical fibers through a one-step coextrusion process (Figure 3d) [68]. Spectral Interrogation of Optical Metal-Cladding Waveguides for Chemical Sensing World Scientific Book Polypyrrole Based Molecularly Imprinted Polymer Platform for Klebsiella pneumonia Detection Sharma, et al, ECS Sensors Plus, 2022 Powered by PDF view Top Catalog Abstract FullText (HTML) Supplementary Information References Relative Articles spectral photometrical oximeters, BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING, MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES, Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions, Enzyme electrodes involving specific analytes or enzymes, Enzyme electrodes involving specific analytes or enzymes for glucose, Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator producing a change of colour, Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00, Biological material, e.g. 5. S. Rashleigh. The accuracy and reproducibility mainly depend on the characteristics of the. Recent advances in flexible and stretchable bio-electronic devices integrated with nanomaterials. Optical waveguide sensor for on-line monitoring of bacteria A grating-coupled planar optical waveguide sensor is presented for sensing of bacteria by evanescent waves. Reproduced with permission [51]. Example: (diode OR solid-state) AND laser [search contains "diode" or "solid-state" and laser], Example: (photons AND downconversion) - pump [search contains both "photons" and "downconversion" but not "pump"]. Optical waveguides and integrated optical devices are promising solutions for many applications, such as medical diagnosis, health monitoring and light therapies. Copyright 2016, Nature Publishing Group; (i) Cross-section image of a citrate-based optical fiber with poly(octamethylene maleate citrate) (POMC) core and poly(octamethylene citrate) (POC) cladding. Various embodiments of the present invention will be described with reference to the accompanying drawings. OCIS codes: (280.4788) Optical sensing and sensors, (130.3120) Integrated optics devices, (050.6624) Subwavelength structures. One promising approach is to integrate the polymeric waveguide with diverse sensing schemes (such as using fluorophores, plasmonic nanostructures, and gratings), where intensity/wavelength/polarization multiplexing technique may be adopted for the signal decoupling. Full-textile wireless flexible humidity sensor for human physiological monitoring. Copyright 2019, Wiley; (d) Coextrusion fabrication of step-index polymer optical fibers from thermoplastic elastomers. encapsulated sensing cells into a slab PEGDA hydrogel waveguide and applied it for toxicity sensing of cadmium-based quantum dots (QDs) in vivo [36]. Henrik C. Pedersen,1 Reproduced with permission [40]. Click here to learn more. Spin-coating; Mold injection; Lithography. demonstrated a gradient-index (GRIN) optofluidic planar waveguide by applying a gradient temperature during the thermal curing of the PDMS [62]. Beijing Renhe Information Technology Co., Ltd. Akpakwu GA, Silva BJ, Hancke GP, Abu-Mahfouz AM. J.G. Copyright 2013, Nature Publishing Group; (c) Photographs of the two hydrogel samples with molecular weight of 0.5 kDa and 5 kDA. In particular, for a single-layer waveguide, the surroundings might be air, water, or biological tissues, where TIR occurs at the waveguide boundaries. Reproduced with permission [39]. First three types of sensors are distinguished: intrinsic, extrinsic and active. Intensity-modulated microbend fiber optic sensor for respiratory monitoring and gating during MRI. By continuing to use this site, you agree to our use of cookies. In this section, we focus on their applications in biomedical sensing, where waveguide sensors, serving as implantable and injectable devices, can be used for continuous and long-term monitoring of biological information inside the body and tissue. presented an implantable hydrogel waveguide with integrated fluorescent proteins for calcium detection, where the calcium ions bond with the immobilized proteins, resulting in fluorescence changes due to the fluorescence resonance energy transfer effect [74]. In the past decades, hydrogels have been extensively investigated for a wide range of biomedical applications such as tissue engineering, wound dressings, and drug delivery, due to their soft and rubbery nature as well as high water contentsimilar to natural soft tissues [38]. Upon stretching, the ionic chains of Ca2+-alginate breaks, providing an energy dissipation, while the covalently crosslinked, long-chain polyacrylamide (PAAm) gives high deformability and maintains the mechanical integrity of the hydrogels. The resonators which are preferably oriented substantially perpendicularly with respect to incoming vibration waves, vibrate when a wave is detected . According to a seventh aspect of the present invention, an optical waveguide system for glucose measurement comprises (a)(1) an optical waveguide device comprising an optical waveguide sensor having a substrate, a first optical waveguide layer formed on a surface of the substrate, an entrance grating and an exit grating contacting with the first optical waveguide layer and being spaced from each other, a second optical waveguide layer located between the entrance grating and the exit grating while being in contact with the first optical waveguide layer, the second optical waveguide layer having a higher refractive index than that of the first optical waveguide layer, a functioning layer containing an enzyme and a coloring reagent formed on the second optical waveguide layer and a meshed electro-conductive thin film positioned above the functioning layer, and (2) a detection unit having a light source configured to emit a light to the first optical waveguide layer, a light detector configured to receive the light coming from the first optical waveguide layer, a cathode configured to contact with the meshed electro-conductive thin film, an anode having an end to which an electrode plate is connected, a central process control unit configured to control a light quantity of the light source, to process signals sent from the light detector and to control an electric voltage applied between the cathode and the anode, an electric power supply circuit having an electric power-receiving induction coil, a serial port connected to the central process control unit and a data transmission induction coil connected to the serial port, and (b) a charging device comprising an electric power transmission induction coil and a data-receiving induction coil connected with the electric power-receiving induction coil and the data transmission induction coil located in the detection unit electromagnetically, and a microcomputer configured to transfer data received by the data-receiving induction coil to an outside computer. Zheng LY, Behrooz M, Li R, Wang XJ, Gordaninejad F. Performance of a bio-inspired spider web. The AgNPs-doped hydrogel optical fibers, having a Youngs modulus comparable to soft biological tissues, were demonstrated for detection and discrimination of bioanalytes from the SERS spectra (Figure 5i). Leal-Junior A, Avellar L, Biazi V, Soares MS, Frizera A et al. Within the context, the use of metamaterial enhances the sensitivity of the sensor. Zhao H., OBrien K., Li S., Shepherd R.F. An optical waveguide sensor for glucose measurement comprises a substrate, a first optical waveguide layer formed on a surface of the substrate, an entrance grating and an exit grating which are formed contacting with the first optical waveguide layer and being spaced from each other, a second optical waveguide layer located between the entrance grating and the exit grating while being in contact with the first optical waveguide layer, the second optical waveguide layer having a higher refractive index than that of the first optical waveguide layer, and a functioning layer containing an enzyme and a coloring reagent which is formed on the second optical waveguide layer. Reproduced with permission [57]. The past decades have witnessed the rapid development in soft, stretchable, and biocompatible devices for applications in biomedical monitoring, personal healthcare, and humanmachine interfaces. Received 2019 Jul 25; Accepted 2019 Aug 28. measuring the change in the intensity of light transmitted in the second optical waveguide layer. Catalog 1. Separate search groups with parentheses and Booleans. Yeo J.C., Lim C.T. Inkjet printing bendable circuits based on an oil-water interface reaction. Step-index optical fiber made of biocompatible hydrogels. The RI of the PDMS core (base/curing agent = 5:1) and cladding (base/curing agent=20:1) were 1.424 and 1.417, respectively. Guo J., Zhou B., Yang C., Dai Q., Kong L. Stretchable and temperature-sensitive polymer optical fibers for wearable health monitoring. Chen Y., Lu B., Chen Y., Feng X. Breathable and stretchable temperature sensors inspired by skin. Fiber Bragg grating sensors have been integrated into functional textiles for wearable monitoring of body temperature [81]. -- Example: "gr?y" retrieves documents containing "grey" or "gray". Roriz P., Carvalho L., Frazo O., Santos J.L., Simes J.A. Development of AR hardware smart helmet including near eye display, holo lens, VBG HMD, ToF and CW lidar sensor, VCSEL array . Various modifications will become possible for those skilled in the art after receiving the teachings of the present disclosure without departing from the scope thereof. Copyright 2015, Wiley. In addition to mechanical sensing, stretchable polymeric optical waveguides have also been investigated for wearable measurements of body temperature [64]. Kang D, Pikhitsa PV, Choi YW, Lee C, Shin SS et al. Naturally derived polymers with a high degree of biocompatibility and biodegradability have been widely used in medical and clinical applications, such as for controlled drug release, cell encapsulation, and regenerating and repairing damaged tissue [41]. Jiang YH, Nayeb-Hashemi H. Dynamic response of spider orb webs subject to prey impact. The hydrogel fibers were made by PAAm hydrogel coated with polyethylene glycol (PEG) for enhanced biocompatibility. The propagation loss of the single-mode rib waveguide was measured to be 0.48 dB/cm at 635 nm. using sub-millimetre waves, infrared, visible or ultraviolet light, Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated, Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator, Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator using reagent-clad optical fibres or optical waveguides, Measuring for diagnostic purposes; Identification of persons, Measuring characteristics of blood in vivo, e.g. Copyright 2015, Optical Society of America; (e) Cross-section image of a biodegradable double-core optical fiber made from cellulose. In general, the optical fiber sensors based on antiresonant reflecting optical waveguide have advantages, such as compact structure, high sensitivity, large dynamic range, and high stability, which appear to have potential applications in researches of structure health monitoring, oil exploiting, and biology detection. The attaching thread caused microbends in the fiber upon stretching, resulting in monotonic transmission changes against strain. In the simplest case this can be a mechanical system that blocks the light as the pressure increases. Furthermore, waveguides made of these materials are highly stiff and rigid, resulting in a significant mechanical mismatch with the soft skins and tissues [33,34]. The implementation of wearable sensors by using stretchable optical waveguides offer a promising approach to overcome the limitations above.