In this paper, we present a microstructured optofluidic in-fiber Raman sensor for the detection of quinolone antibiotic residue in a water environment based on Ag surface-enhanced Raman scattering (SERS) substrate grown on the surface of the suspended core of micro-hollow optical fiber (MHF). Here, MHF has a special structure with a suspended core and a microchannel inside, which can become a natural in-fiber optofluidic device. Meanwhile, the self-assembled Ag SERS substrate can be grown on the suspended core's surface through chemical bonds, forming a microstructured optofluidic device with a Raman enhancement effect.
View Article and Find Full Text PDFIn this paper, we propose a self-assembled graphene oxide (GO)/Ag NPs SERS Raman sensor based on a novel type of optofluidic MHF as a point-of-care testing (POCT) device. This device is used to diagnose jaundice and its related diseases through on-line detection of free bilirubin content in human serum. This optofluidic Raman sensor is composed of a microstructured hollow fiber (MHF) with a microstructured channel and a suspended core, which allows the sample solution to flow in the channel while interacting with the strong evanescent field on the suspended core.
View Article and Find Full Text PDFA cheap, compact, and simply prepared all-fiber bidirectional optical modulator based on the Pockels effect of water and the band population effect was first, to the best of our knowledge, proposed and demonstrated. The transparent conductive oxide indium-tin-oxide (ITO) was coated on the surface of a nonadiabatic microfiber and first used as a modulating electrode on the microfiber. The device was realized by just submerging the microfiber in water.
View Article and Find Full Text PDFIn this Letter, we propose a microstructured in-fiber optofluidic surface-enhanced Raman spectroscopy (SERS) sensor for the initial inspection of uremia through the detection of unlabeled urea and creatinine. As a natural microfluidic device, microstructured hollow fiber has a special structure inside. Through chemical bonds, the SERS substrate can be modified and grown on the surface of the suspended core.
View Article and Find Full Text PDFAll-fiber modulators and switches have drawn great interest in the photonics domain, and they are applied in viable photonic and optoelectronic devices. In this work, with the assistance of an agarose membrane, aspherical gold nanoparticles are embedded on the surface of the microfiber treated with the piranha solution. An all-fiber Mach-Zehnder interferometer was used to realize a low-cost, low-loss, and conveniently prepared all-fiber phase modulator.
View Article and Find Full Text PDFInt J Environ Res Public Health
May 2019
Chromium contamination of drinking water has become a global problem due to its extensive use in industry. The most commonly used methods for chromium detection in water are laboratory-based methods, such as atomic absorption spectroscopy and mass spectroscopy. Although these methods are highly selective and sensitive, they require expensive maintenance and highly trained staff.
View Article and Find Full Text PDFArsenic contamination of drinking water is a global concern. Standard laboratory methods that are commonly used for arsenic detection in water, such as atomic absorption spectroscopy and mass spectroscopy, are not suitable for mass monitoring purposes. Autonomous microfluidic detection systems combined with a suitable colorimetric reagent could provide an alternative to standard methods.
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