Increasing customer demand for durable and functional apparel manufactured in a sustainable manner has created an opportunity for nanomaterials to be integrated into textile substrates. Nanomoieties can induce stain repellence, wrinkle-freeness, static elimination, and electrical conductivity to fibers without compromising their comfort and flexibility. Nanomaterials also offer a wider application potential to create connected garments that can sense and respond to external stimuli via electrical, color, or physiological signals. This review discusses electronic and photonic nanotechnologies that are integrated with textiles and shows their applications in displays, sensing, and drug release within the context of performance, durability, and connectivity. Risk factors including nanotoxicity, nanomaterial release during washing, and environmental impact of nanotextiles based on life cycle assessments have been evaluated. This review also provides an analysis of nanotechnology consolidation in the textiles ...

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Nanotechnology in Textiles

Surface plasmon resonance technique in collaboration with optical fiber technology has brought tremendous advancements in sensing of various physical, chemical, and biochemical parameters. In this review article, we present the principle of SPR technique for sensing and various designs of the fiber optic SPR probe reported for the enhancement of the sensitivity of the sensor. In addition, we present few examples of the surface plasmon resonance- (SPR-) based fiber optic sensors. The present review may provide researchers valuable information regarding fiber optic SPR sensors and encourage them to take this area for further research and development.

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Surface Plasmon Resonance-Based Fiber Optic Sensors: Principle, Probe Designs, and Some Applications

We report a miniaturized fiber inline Fabry-Perot interferometer (FPI), with an open micro-notch cavity fabricated by one-step fs laser micromachining, for highly sensitive refractive index measurement. The device was tested for measurement of the refractive indices of various liquids including isopropanol, acetone and methanol at room temperature, as well as the temperature-dependent refractive index of deionized water from 3 to 90 degrees C. The sensitivity for measurement of refractive index change of water was 1163 nm/RIU at the wavelength of 1550 nm. The temperature cross-sensitivity of the device was about 1.1x10(-6) RIU/degrees C. The small size, all-fiber structure, small temperature dependence, linear response and high sensitivity, make the device attractive for chemical and biological sensing.

/pdf/temperature-insensitive-miniaturized-fiber-inline-fabry-r6hevcd4jf.pdf

Temperature-insensitive miniaturized fiber inline Fabry-Perot interferometer for highly sensitive refractive index measurement

Current status of micro- and nano-structured optical fiber sensors

Demand for accessible and affordable healthcare for infectious and chronic diseases present significant challenges for providing high-value and effective healthcare. Traditional approaches are expanding to include point-of-care (POC) diagnostics, bedside testing, and community-based approaches to respond to these challenges.1 Innovative solutions utilizing recent advances in mobile technologies, nanotechnology, imaging systems, and microfluidic technologies are envisioned to assist this transformation.

Infectious diseases have considerable economic and societal impact on developing settings. For instance, malaria is observed more commonly in sub-Saharan Africa and India.2 The societal impact of acquired immune deficiency syndrome (AIDS) and tuberculosis is high, through targeting adults in villages and leaving behind declining populations.3 In resource-constrained settings, it is estimated that about 32% of the disease burden is from communicable diseases such as respiratory infections, AIDS, and malaria, while 43% of the burden is from noncommunicable diseases, such as cardiovascular diseases, neuropsychiatric conditions, and cancer.4 Developing diagnostic platforms that are affordable, robust, and rapid-targeting infectious diseases is one of the top priorities for improving healthcare delivery in the developing world.5 The early detection and monitoring of infectious diseases and cancer through affordable and accessible healthcare will significantly reduce the disease burden and help preserve the social fabric of these communities. Further, improved diagnostics and disease monitoring technologies have potential to enhance foreign investment, trade, and mobility in the developing countries.6

Highly sensitive and specific lab assays such as cell culture methods, polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay (ELISA) are available for diagnosis of infectious diseases in the developed world. They require sample transportation, manual preparation steps, and skilled and well-trained technicians. These clinical conventional methods provide results in several hours to days, precluding rapid detection and response at the primary care settings. Another diagnostic challenge is identifying multiple pathogens. Since common symptoms like sore throat and fever can be caused by multiple infectious agents (e.g., bacteria and viruses), it is important to accurately identify the responsible agent for targeted treatment. Therefore, high-throughput sensors for multiplexed identification would help improve patient care.7

Medical instruments in centrally located institutions in the developed world rely on uninterrupted electricity and running water and require controlled environmental conditions. It may not be viable to satisfy some of these criteria in some POC settings, where well-trained healthcare personnel are not available and clean water access is unreliable.7,8 Further, in remote settings without infrastructure, rain and dust can act as contaminants.7 Diagnostic devices for POC testing in these settings are identified by the World Health Organization to be affordable, sensitive, user-friendly, specific to biological agents, and providing rapid response to small sample volumes.9 Optical biosensor devices are emerging as powerful biologic agent detection platforms satisfying these considerations.10

Optical sensing platforms employ various methods, including refractive index change monitoring, absorption, and spectroscopic-based measurements.11 Optical sensors that are based on refractive index monitoring cover a range of technologies, including photonic crystal fibers, nano/microring resonator structures, interferometric devices, plasmonic nano/micro arrays, and surface plasmon resonance (SPR)-based platforms.11,12 The latter two are plasmonic-based technologies. Plasmonics is an enabling optical technology with applications in disease monitoring, diagnostics, homeland security, food safety, and biological imaging applications. The plasmonic-based biosensor platforms along with the underlying technologies are illustrated in the Figure ​Figure1.1. Here, we reviewed SPR, localized surface plasmon resonance (LSPR), and large-scale plasmonic arrays (e.g., nanohole arrays).



Figure 1

Plasmonic-based technologies for versatile biosensor applications. SPR stands for surface plasmon resonance, LSPR for localized surface plasmon resonance, SPRi for surface plasmon resonance imaging, and SERS for surface-enhanced Raman scattering.

https://canarycenter.stanford.edu/content/dam/sm/canarycenter/documents/research/bamm-lab/ChemicalReview.pdf

Advances in Plasmonic Technologies for Point of Care Applications

The concept of photonic bandgap fiber-based surface plasmon resonance sensor operating with low refractive index analytes is developed. Plasmon wave on the surface of a thin metal film embedded into a fiber microstructure is excited by a leaky Gaussian-like core mode of a fiber. We demonstrate that by judicious design of the photonic crystal reflector, the effective refractive index of the core mode can be made considerably smaller than that of the core material, thus enabling efficient phase matching with a plasmon, high sensitivity, and high coupling efficiency from an external Gaussian source, at any wavelength of choice from the visible to near-IR. To our knowledge, this is not achievable by any other traditional sensor design. Moreover, unlike the case of total internal reflection waveguide-based sensors, there is no limitation on the upper value of the waveguide core refractive index, therefore, any optical materials can be used in fabrication of photonic bandgap fiber-based sensors. Based on numerical simulations, we finally present designs using various types of photonic bandgap fibers, including solid and hollow core Bragg fibers, as well as honeycomb photonic crystal fibers. Amplitude and spectrum based methodologies for the detection of changes in the analyte refractive index are discussed. Furthermore, sensitivity enhancement of a degenerate double plasmon peak excitation is demonstrated for the case of a honeycomb fiber. Sensor resolutions in the range 7 * 10(-6) -5 * 10(-5) RIU were demonstrated for an aqueous analyte.

Photonic bandgap fiber-based Surface Plasmon Resonance sensors.

In the proposed photonic crystal waveguide-based surface plasmon resonance (SPR) sensor, a plasmon wave on the surface of a thin metal film is excited by a Gaussian-like leaky mode of an effectively single-mode photonic crystal waveguide. By judicious design of a photonic crystal waveguide, the effective refractive index of a core mode can be made considerably smaller than that of the core material, thus enabling efficient phase-matching with a plasmon, high sensitivity, and high coupling efficiency from an external Gaussian source, at any wavelength of choice from the visible to near infrared (IR), which is, to our knowledge, not achievable by any other design. Moreover, unlike the case of total internal reflection (TIR) waveguide-based sensors, a wide variety of material combinations can be used to design photonic crystal waveguide-based sensors as there is no limitation on the value of the waveguide core refractive index. This sensor design concept was implemented using planar multilayer photo...

Majid Fassi Fehri

Papers

Photonic bandgap fiber-based Surface Plasmon Resonance sensors.

Photonic Crystal Fiber and Waveguide-Based Surface Plasmon Resonance Sensors for Application in the Visible and Near-IR

LBLOCA in CANDU-NG cooled by light water

Further improving LBLOCA resistance of CANDU cooled by light water