A novel TiO-modified THPP-BCP composite optical waveguide sensor for the determination of ethylenediamine at ppb level.

Composite thin films OWG sensors show higher sensitivity than single film-based OWG sensors, making them particularly useful in the detection of trace gases. In this work, we developed a new tetra hydroxyphenyl porphyrin (THPP)-bromocresol purple (BCP)/TiO gel composite film-based OWG (THPP-BCP/TiO-OWG) sensor for identifying ethylenediamine (EDA) gas. The fabricated sensor was characterized using ultraviolet and infrared spectroscopy and atomic force microscopy.

Development of composite optical waveguide based on azobenzene-modified titanium metal-organic framework film for study of gas adsorption kinetics.

This study investigates the fabrication and gas adsorption kinetics of an azobenzene (AZB)-modified titanium metal-organic framework (AZB@Ti-MOF) film composite optical waveguide (COWG) that recognizes ethylenediamine (EDA) gas. After modification with AZB, the surface of the Ti-MOF film became rough and evolved from a hemispherical structure to a petal-like structure; a large pore size and small specific surface area accompanied the evolution of the surface morphology. The AZB@Ti-MOF film COWG exhibited a positive response to EDA gas co-existing with the same concentration (1000 ppm) of benzenes, amines, and acidic gases.

Metallic Effects on p-Hydroxyphenyl Porphyrin Thin-Film-Based Planar Optical Waveguide Gas Sensor: Experimental and Computational Studies.

Metal effects on the gas sensing behavior of metal complexes of 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin (THPP) thin film was investigated in terms of detecting NO gas by the planar optical waveguide. For this purpose, several THPP and metal complexes were synthesized with different central metal ions: Co(II), Ni(II), Cu(II), and Zn(II). Planar optical gas sensors were fabricated with the metalloporphyrins deposited on K ion-exchanged soda-lime glass substrate with the spin coating method serving as host matrices for gas interaction.

Exploring optical and electrical gas detection based on zinc-tetra-phenyl-porphyrin sensitizer.

We developed optical waveguide (OWG), ultraviolet-visible spectrophotometry (UV-vis), and electrically operated gas sensors utilizing zinc-tetra-phenyl-porphyrin (ZnTPP) as sensitizer. Strikingly, ZnTPP thin-film/K-exchanged glass OWG sensing element exhibits a superior signal-to-noise ratio of 109.6 upon 1 ppm NO gas injection, which is 29.

Sensing Behavior of Metal-Free Porphyrin and Zinc Phthalocyanine Thin Film towards Xylene-Styrene and HCl Vapors in Planar Optical Waveguide.

The sensing behavior of a thin film composed of metal-free 5, 10, 15, 20-tetrakis (p-hydroxy phenyl) porphyrin and zinc phthalocyanine complex towards m-xylene, styrene, and HCl vapors in a homemade planar optical waveguide (POWG), was studied at room temperature. The thin film was deposited on the surface of potassium ion-exchanged glass substrate, using vacuum spin-coating method, and a semiconductor laser light (532 nm) as the guiding light. Opto-chemical changes of the film exposing with hydrochloric gas, m-xylene, and styrene vapor, were analyzed firstly with UV-Vis spectroscopy.

Fabrication and characterization of photo-responsive metal-organic framework membrane for gas sensing using planar optical waveguide sensor.

A facile, novel fabrication approach using UV light irradiation was proposed to fabricate a photo-responsive metal-organic framework (PR-MOF-1, [Zn-(bdc)-(dpNDI)], where bdc = benzene-1,4-dicarboxylic acid; dpNDI = N,N'-di(4-pyridyl)-1,4,5,8-naphthalenetetracarboxy diimide) membrane. The morphology of the PR-MOF-1 framework evolved from a honeycomb porous structure to a densified ladder-layered structure after 60 min of UV-light illumination. The as-grown film was optically transparent and exhibited a greater sensing response to ethylenediamine (EDA) gas in the presence of interfering substances such as ammonia and dimethylamine as well as benzene, toluene, xylene, and styrene gases, as measured using an asymmetric planar optical waveguide gas sensor.

Substituent Effect on Porphyrin Film-Gas Interaction by Optical Waveguide: Spectrum Analysis and Molecular Dynamic Simulation.

Substituent effect on optical gas sensing performance in porphyrin-based optical waveguide detection system was studied by molecular dynamics simulation (MDS), absorption/emission spectrum analysis, and optical waveguide (OWG) detection. The affinities of porphyrin with seven types of substituents (-H, -OH, -tBu, -COOH, -NH, -OCH, -SO) on para position of meso-phenyl porphyrin toward gas molecules in adsorption process were studied in different size of boxes with the same pressure and concentration. Analyte gases (CO, HS, HCl, NO) were exposed to porphyrin film in absorption spectrophotometer, and in OWG with evanescent field excited by a guiding laser light with 670 nm wavelength.

Application of bromocresol purple nanofilm and laser light to detect mutton freshness.

Optical waveguide gas sensor with bromocresol purple (BCP) nano-film (70-80 nm) composited with silicone deposited on surface of K-ion exchanged glass slide was fabricated and applied to detect amine gases released during mutton spoilage to test mutton freshness with the help of laser light (632 m). Gas sensing measurements (output light intensity vs. time) proved its high selectivity and good sensitivity (0.

Correction: Gulimire Tuerdi, Nuerguli Kari, Yin Yan, Patima Nizamidin and Abliz Yimit *. A Functionalized Tetrakis(4-Nitrophenyl)Porphyrin Film Optical Waveguide Sensor for Detection of HS and Ethanediamine Gases. 2017, , 2717.

The authors wish to make the following corrections to this paper [...

Membrane-Protected Molecularly Imprinted Polymer for the Microextraction of Indole-3-butyric Acid in Mung Bean Sprouts.

Based on the hollow fiber protected molecularly imprinted polymer, a micro-solid-phase extraction (μ-SPE) method was developed and applied for the analysis of indole-3-butyric acid in mung bean sprouts by high-performance liquid chromatography. The extraction conditions of the μ-SPE method were optimized using L(3) orthogonal, and optimum conditions were found as follows: pH of sample solution was 2.0, chloroform was the organic solvent for embedding the μ-SPE bars, and acetonitrile was the desorption solvent.

In situ growth and optical gas adsorption performance of Zn(ii) metal-organic framework membranes at room temperature.

A series of Zn(ii) metal-organic framework membranes, [Zn2(bdc)2(dpNDI)]n (where bdc = terephthalic acid and dpNDI = N,N'-di(4-pyridyl)-1,4,5,8-naphthalenediimide), were grown on a tin-diffused glass substrate using an in situ growth method at room temperature (20 °C). [Zn2(bdc)2(dpNDI)]n thin films were optically transparent and characterized by absorbance, thickness, refractive index and fluorescence techniques. After 20 h of growth, they displayed a complete honeycomb framework with a larger pore size (380 nm), uniform surface and lower refractive index.

Optical-Electricity Gas-Sensing Property Detection of SDBS-WO Film at Room Temperature.

In this work, sodium dodecyl benzene sulfonate (SDBS) was used as a dispersing agent; a WO nanoparticle suspension was used as a sensing material. The SDBS-WO thin film/Sn-doped glass optical waveguide sensor element was prepared by spin coating. The sensing material was characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM).

Detection of Trimethylamine Based on a Manganese Tetraphenylporphyrin Optical Waveguide Sensing Element.

The sensitive detection of trimethylamine has been accomplished by using a homogeneous optical waveguide sensor system. Also the sensor can be easily fabricated by using tetraphenylporphyrin manganese (MnTPP) as sensitive materials to detect different volatile organic compounds (VOC). NMR (H-NMR), field-emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS), infrared (IR), and ultraviolet-visible (UV-vis) instrumental means were used to characterize its structure.

Optochemical properties of gas-phase protonated tetraphenylporphyrin investigated using an optical waveguide NH sensor.

5,10,15,20-Tetraphenylporphyrin (TPP) was synthesized, and a glass optical waveguide (OWG, which restricts and maintains the light energy in a specific, narrow space and propagates along the space axially) was coated with a gas-phase protonated TPP thin film to develop a sensor for NH gas detection. The results show that the TPP thin film agglomerated into H-based J-type aggregates after HS gas exposure. The molecules in the protonated TPP film OWG sensor acted as NH receptors because the gas-phase protonated TPP film morphologically changed from J-type aggregates into free-base monomers when it was deprotonated by NH exposure.

A Functionalized Tetrakis(4-Nitrophenyl)Porphyrin Film Optical Waveguide Sensor for Detection of H₂S and Ethanediamine Gases.

The detection of hydrogen sulfide (H₂S) and ethanediamine, toxic gases that are emitted from industrial processes, is important for health and safety. An optical sensor, based on the absorption spectrum of tetrakis(4-nitrophenyl)porphyrin (TNPP) immobilized in a Nafion membrane (Nf) and deposited onto an optical waveguide glass slide, has been developed for the detection of these gases. Responses to analytes were compared for sensors modified with TNPP and Nf-TNPP composites.

Room-temperature HS Gas Sensor Based on Au-doped ZnFeO Yolk-shell Microspheres.

Room-temperature type HS sensing devices that use Au-doped ZnFeO yolk-shell microspheres as the active material have been fabricated using a solvothermal method as well as subsequent annealing and a chemical etching process. The samples are characterized using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), field-emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS). The results demonstrate that the doping of Au does not change the spinel structure of the products, which were yolk-shell microspheres, while the particle size varied with the Au doping concentration.

Optical waveguide sensor of volatile organic compounds based on PTA thin film.

In this study, a sensitive optical waveguide (OWG) sensor for the detection and identification of volatile organic compounds (VOCs) was reported. The sensing membrane is constructed by immobilization of peroxopolytungsten acid (PTA) thin film over a single-mode potassium ion (K(+)) exchanged glass OWG by spin-coating method. A laser beam was coupled into and out of the glass optical waveguide using prism couplers, and dry air functioned as a carrier gas.

Optical waveguide BTX gas sensor based on polyacrylate resin thin film.

An optical sensor sensitive to BTX has been developed by spin coating a thin film of polyacrylate resin onto a tin- diffused glass optical waveguide. A pair of prism coupler was employed for optical coupling matched with diiodomethane (CH2l2). The guided wave transmits in waveguide layer and passes through the film as an evanescent wave.

Thin film composite optical waveguides for sensor applications: a review.

We review the design and fabrication of thin-film composite optical waveguides (OWG) with high refractive index for sensor applications. A highly sensitive optical sensor device has been developed on the basis of thin-film, composite OWG. The thin-film OWG was deposited onto the surface of a potassium-ion-exchanged (K(+)) glass OWG by sputtering or spin coating (5-9mm wide, and with tapers at both ends).

[Selection of matrix modifier for GF-AAS determination of trace lead in soil watered with waste water and its application].

The rapid and direct method of selection of the matrix modifier for the determination of trace lead in soil watered with waste water by graphite furnace atomic absorption spectrometry under the best matrix modifier selected has been developed. The effect of the matrix modifiers including NH4 Hz2PO4, (NH4)3PO4, NH4CI, Pd-Mg, NH4H2PO4+MgNO3+NH4NO3 etc. was determined by using graphite furnace atomic absorption spectroscopy.

Nafion film/K(+)-exchanged glass optical waveguide sensor for BTX detection.

An optical waveguide (OWG) sensor for the detection of BTX gases is reported. The highly sensitive element of this sensor was made by coating the copper Nafion film over a single-mode potassium ion exchanged glass OWG. We used the OWG sensor to detect toluene gas as a typical example BTX gas.