Vibrational structure analysis of cobalt fluoro-porphyrin surface coatings on gallium phosphide

2018 ◽  
Vol 22 (06) ◽  
pp. 461-466 ◽  
Author(s):  
Diana Khusnutdinova ◽  
Anna M. Beiler ◽  
Brian L. Wadsworth ◽  
Sylvia K. Nanyangwe ◽  
Gary F. Moore
Keyword(s):  
Ftir Spectroscopy ◽  
Gallium Phosphide ◽  
Plane Deformation ◽  
Grazing Angle ◽  
Spectroscopic Techniques ◽  
Step Method ◽  
Pyridyl Nitrogen ◽  
Surface Attachment ◽  
Modified Surfaces ◽  
Surface Graft

Grazing angle attenuated total reflectance Fourier transform infrared (GATR–FTIR) spectroscopy is used to characterize chemically modified gallium phosphide (GaP) surfaces containing grafted cobalt(II) porphyrins with 3-fluorophenyl substituents installed at the meso-positions. In these hybrid constructs, porphyrin surface attachment is achieved using either a two-step method involving coordination of cobalt fluoro-porphyrin metal centers to nitrogen sites on an initially applied thin-film polypyridyl surface coating, or via a direct modification strategy using a cobalt fluoro-porphyrin precursor bearing a covalently bonded 4-vinylphenyl surface attachment group at a [Formula: see text]-position. Both surface-attachment chemistries leverage the UV-induced immobilization of alkenes but result in distinct structural connectivities of the grafted porphyrin units and their associated vibrational spectra. In particular, the in-plane deformation vibrational frequency of metalloporphyrin components in samples prepared via coordination to the polymeric interface is characterized by an eight wavenumber shift to higher frequencies compared to that measured on metalloporphyrin-modified surfaces prepared using the one-step attachment method. The more rigid ring structure in the polymeric architecture is consistent with coordination of porphyrin cobalt centers to pyridyl-nitrogen sites on the surface graft. These results demonstrate the use of GATR–FTIR spectroscopy as a sensitive tool for characterizing porphyrin-modified surfaces with absorption signals that are close to the detection limits of many common spectroscopic techniques.

scholarly journals 2125. Staphylococcus Species Identification by Fourier Transform Infrared (FTIR) Spectroscopic Techniques: A Cross-Lab Study

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S720-S720
Author(s):  
Tamao Tsutsumi ◽  
Alok Shah ◽  
Lisa M T Lam ◽  
Sanmarie Schlebusch ◽  
Annika Krueger ◽  
...  
Keyword(s):  
Fourier Transform ◽  
16S Rrna ◽  
Ftir Spectroscopy ◽  
Species Identification ◽  
Ftir Spectra ◽  
16S Rrna Sequencing ◽  
Spectroscopic Techniques ◽  
Rrna Sequencing ◽  
Perilesional Skin ◽  
Spectral Databases

Abstract Background Staphylococcus aureus is well known to be associated with atopic dermatitis. Recent studies also report S. aureus presence in lesional skin of squamous cell carcinoma (SCC) and its precursor lesion, actinic keratosis (AK). Therefore, it is of potential clinical interest to monitor skin S. aureus colonization on AK lesions. Fourier transform infrared (FTIR) spectroscopy is a cost-effective, nondestructive, and reagent-free technique for rapid microbial identification. It is based on the use of spectral databases developed with well-characterized strains in conjunction with the application of multivariate statistical analysis to elaborate classification models. In the present cross-lab study, spectral databases containing FTIR spectra of over 1000 staphylococcal isolates obtained from reference and clinical microbiology laboratories across Canada were employed in the FTIR spectroscopic identification of Staphylococcus spp. isolated from AK, SCC and perilesional skin of patients at the Princess Alexandra Hospital Dermatology Clinic in Brisbane, Australia. Methods FTIR spectra of 51 staphylococcal isolates from AK, SCC and perilesional skin were acquired by both attenuated total reflectance (ATR)-FTIR and transflection-FTIR spectroscopy. All isolates had been previously characterized by 16S rRNA sequencing. ATR- and transflection-FTIR spectra were recorded in triplicate from isolated colonies taken from the same agar plate. Identification of the bacteria was based on the similarities of their spectra with those in ATR- and transflection-FTIR spectral databases originating from the Canadian lab. Results Among the 51 staphylococcal isolates included in this study, identification of S. aureus (n = 24) with 100% specificity and 100% sensitivity was achieved by both ATR- and transflection-FTIR spectroscopy. Overall, FTIR-based species identification was in 90.2% concordance with 16S rRNA sequencing. Conclusion This cross-lab study demonstrates the applicability of Canadian isolate-based ATR- and transflection-FTIR spectral databases for the identification of clinical staphylococcal isolates obtained in Australia. The results support the potential utility of FTIR spectroscopic techniques to monitor skin S. aureus colonization on AK lesions. Disclosures All authors: No reported disclosures.

scholarly journals Synthesis and thermal properties of new copolyesters based on polycaprolactone

e-Polymers ◽  
2012 ◽  
Vol 12 (1) ◽  
Author(s):  
El Miloud Maafi ◽  
Fouad Malek ◽  
Lan Tighzert ◽  
Fouad Laoutid ◽  
Philippe Dubois
Keyword(s):  
Thermal Properties ◽  
Ftir Spectroscopy ◽  
Polymer Chain ◽  
Synthesis Method ◽  
Aromatic Rings ◽  
Step Method ◽  
One Step ◽  
Random Distributions ◽  
Poly Caprolactone ◽  
C Nmr

AbstractSeveral copolyesters were synthesized from carboxytelechelic poly( - caprolactone) and bis(2-hydroxyethyl)terephthalate (BHET), using a two-step method and a one-step method providing regular and random distributions of starting comonomers in the copolyester chains, respectively. Even with an identical molar comonomer composition, the properties of obtained copolyesters depended on the synthesis method, therefore the comonomer distribution along the polymer chain. The copolyester structure was characterized by 1H and 13C NMR and FTIR spectroscopy. The thermal properties of synthesized copolyesters were also studied by DSC and TGA demonstrating the influence of aromatic rings spread along the macromolecular polyester chain.

scholarly journals Investigating the Adsorption Behavior and Mechanism of Eu(III) and Au(III) on β-cyclodextrin/polyethylenimine Functionalized Waste Paper

2021 ◽  
Author(s):  
Fenglei Liu ◽  
Shan Hua ◽  
Qingyuan Hu ◽  
Chao Wang ◽  
baowei hu
Keyword(s):  
Vital Role ◽  
Adsorption Behavior ◽  
Waste Paper ◽  
Spectroscopic Techniques ◽  
Spectroscopy Analysis ◽  
Step Method ◽  
Structure Morphology ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Redox Interaction

Abstract A bio-adsorbent (DAWP-PEI-β-CD) was facilely prepared by introducing polyethylenimine (PEI) and β-cyclodextrin (β-CD) into dialdehyde waste paper (DAWP) via a facile two-step method. Various physicochemical and spectroscopic techniques (FT-IR, XRD, SEM, NMR, XPS) were applied to characterize the structure, morphology and composition of the as-prepared adsorbents. Investigation results showed that the pH values, reaction temperature and contact time played a vital role in uptake of Eu(III) and Au(III). Meanwhile, the adsorption behavior of Eu(III) and Au(III) could be fitted felicitously with the Langmuir and the Pseudo-second-order models, and the saturated adsorption amounts of Eu(III) (pH = 6.0) and Au(III) (pH = 2.0) onto DAWP-PEI-β-CD were 424.2 and 241.3 mg/g, respectively. Further advanced spectroscopy analysis revealed that the elimination of Eu(III) was attributed to host-guest inclusion and surface complexation interaction, while adsorption of Au(III) might stem from a combination of electrostatic attraction, chelation, host-guest inclusion and redox interaction. This study demonstrated that DAWP-PEI-β-CD was a promising environmental functional material to separation and enrichment of Eu(III) and Au(III) from contaminated water.

scholarly journals Application of Spectroscopic Techniques in Early Detection of Fungal Plant Pathogens

2021 ◽  
Author(s):  
Ritesh Kumar ◽  
Shikha Pathak ◽  
Nishant Prakash ◽  
Upasna Priya ◽  
Abhijeet Ghatak
Keyword(s):  
Fluorescence Spectroscopy ◽  
Ftir Spectroscopy ◽  
Pathogen Detection ◽  
Plant Pathogens ◽  
Spectroscopic Techniques ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Flight Mass Spectrometry ◽  
Fungal Phytopathogens ◽  
Tof Ms

Among the plant pathogens, around 85% of diseases in plants are caused by fungi. Rapid and accurate detection of fungal phytopathogens up to the species level is crucial for the implementation of proper disease control strategies, which were previously relied on conventional approaches. The conventional identification methods have been replaced by many rapid and accurate methods like high throughput sequencing, real-time polymerase chain reaction (PCR), serological and spectroscopic technique. Among these rapid pathogen detection techniques, spectroscopy is a rapid, cost-effective, non-destructive method and does not require sample preparation. Nowadays, visible, infrared and near-infrared rays are commonly employed for pathogen detection. Fluorescence Spectroscopy, Nuclear Magnetic Resonance (NMR) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, Attenuated Total Reflection (ATR)-FTIR spectroscopy, Raman Spectroscopy, Matrix-assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS). Biocontrol fungus-like Trichoderma spp. can be detected with the help of MALDI-TOF MS. Fluorescence spectroscopy used fluorescence emanating from the sample and successfully used in the detection of powdery mildew (Blumeria graminis). Hyperspectral imaging is an advanced approach which uses artificial intelligence in plant disease detection. This literature discusses briefly about the features of above-mentioned spectroscopy techniques which may impel the general understanding and propel the research activities.

Characterization of thermal inkjet technology TNT deposits by fiber optic-grazing angle probe FTIR spectroscopy

2005 ◽  
Author(s):  
Oliva M. Primera-Pedrozo ◽  
Leonardo Pacheco-Londono ◽  
Orlando Ruiz ◽  
Michael Ramirez ◽  
Yadira M. Soto-Feliciano ◽  
...  
Keyword(s):  
Ftir Spectroscopy ◽  
Fiber Optic ◽  
Grazing Angle ◽  
Angle Probe

Preparation and Characterization of FeCo2O4 Nanoparticles: A Robust and Reusable Nanocatalyst for the Synthesis of 3,4-Dihydropyrimidin- 2(1H)-thiones and Thiazolopyrimidines

2019 ◽  
Vol 15 (6) ◽  
pp. 637-646
Author(s):  
Farah Sadat Mousavi-Moghadam ◽  
Mohammad Ali Ghasemzadeh
Keyword(s):  
Average Particle Size ◽  
Reaction Times ◽  
Chloroacetic Acid ◽  
Aromatic Aldehydes ◽  
Average Particle ◽  
Spectroscopic Techniques ◽  
Magnetic Nanocatalyst ◽  
Step Method ◽  
Solvent Free Conditions ◽  
Three Component Reaction

Background:The present research describes a mild and efficient method for the synthesis of 3,4-dihydropyrimidine-2(1H)-thiones and thiazolopyrimidine via multi-component reactions using FeCo2O4 nanoparticles. It was found that FeCo2O4 nanoparticles act as a powerful and effective catalyst. The prepared catalyst was characterized by the various spectroscopic techniques.Objective:The three-component reaction of thiourea, aromatic aldehydes and ethyl acetoacetate was catalyzed by FeCo2O4 nanoparticles. Next, the prepared 3,4-dihydropyrimidin-2(1H)-thiones were applied for the preparation of thiazolopyrimidines via the reactions of 3,4-dihydropyrimidine-2(1H)- thiones, chloroacetic acid, and aromatic aldehydes in the presence of FeCo2O4 nanoparticles.Methods:The FeCo2O4 nanoparticles were synthesized by a facile one-step method and the structure determination of the catalyst has been done using spectral techniques.:Then, the prepared nanocatalyst was used in the synthesis of 3,4-dihydropyrimidin-2(1H)-thiones and thiazolopyrimidines under solvent-free conditions at 80°C.Results:FeCo2O4 nanoparticles as a magnetic nanocatalyst were applied as a catalyst in the synthesis of some heterocyclic compounds in excellent yields and short reaction times. The average particle size of the catalyst is found to be 30-40 nm. The study on the reusability of the FeCo2O4 nanoparticles showed the recovered catalyst could be reused fifth consecutive times. We propose that FeCo2O4 nanoparticles act as a Lewis acid cause to increase electrophilicity of carbonyl groups of substrates and intermediates to promote the reactions.Conclusion:The present research introduced various advantageous including excellent yields, short reaction times, simple workup procedure and recyclability of the FeCo2O4 NPs in order to the synthesis of 3,4-dihydropyrimidin-2(1H)-thiones and thiazolopyrimidines.

scholarly journals Hybrid polymers bearing oligo-l-lysine(carboxybenzyl)s: synthesis and investigations of secondary structure

RSC Advances ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 1287-1295 ◽  
Author(s):  
Merve Basak Canalp ◽  
Wolfgang H. Binder
Keyword(s):  
Secondary Structure ◽  
Ftir Spectroscopy ◽  
Chain Length ◽  
Secondary Structures ◽  
Spectroscopic Techniques ◽  
Hybrid Polymers ◽  
Dynamic Folding

We demonstrate the influence of chain length of segmented polymers bearing dynamic folding elements onto the formation of secondary structures with the help of spectroscopic techniques such as CD and FTIR-spectroscopy in a helicogenic solvent.

New Dinuclear Transition Metal Complexes with the [M2(μ-dhbq)]n+ Core and 2-(2′-Pyridyl)quinoxaline (L) as a Terminal Ligand: Preparation and Characterization (dhbq2-= the Dianion of 2,5-Dihydroxy -1,4- benzoquinone; M = AgI, MnII, CoII, NiII, CuII, RuII, PdII, FeIII, RhIII; n = 0, 2, 4)

2001 ◽  
Vol 56 (4-5) ◽  
pp. 394-402 ◽  
Author(s):  
Sahar I. Mostafa ◽  
Spyros P. Perlepes ◽  
Nick Hadjiliadis
Keyword(s):  
Solid State ◽  
Nitrogen Atom ◽  
Transition Metal Complexes ◽  
Metal Ion ◽  
Spectroscopic Techniques ◽  
Pyridyl Nitrogen ◽  
Terminal Ligand ◽  
Square Planar ◽  
Elemental Analyses ◽  
Bidentate Chelate

Abstract Synthetic procedures are described that allow access to the new complexes [Mn2(dhbq)L2(H2O)4 (1), [Fe2(dhbq)L2(H2O)4](NO3)4 · 6H2O (2), [Co2(dhbq)Cl2L2(H2O)2] (3), [Ni2(dhbq)Cl2L2(H2O)2] (4), [Cu2(dhbq)Cl2L2(H2O)2] (5), [Ru2(dhbq)L2(H2O)4](ClO4)2 (6), [Rh2(dhbq)Cl2L2(H2O)2]Cl2·2H2O (7), [Pd2(dhbq)L2]Cl2·5H2O (8) and [Ag2(dhbq)L2] (9), where dhbq2- is the dianion of 2,5-dihydroxy-1,4-benzoquinone and L is the biheteroaromatic ligand 2-(2′-pyridyl)quinoxaline. The new complexes were characterized by elemental analyses and by a variety of physical and spectroscopic techniques. Dinuclear structures are assigned for the complexes in the solid state. The two metal ions are bridged by the bischelating dhbq2- ion, while L behaves as a bidentate chelate with the 2′-pyridyl nitrogen and the nearest quinoxaline nitrogen atom as the ligand atoms. The metal ion coordination geometries are octahedral, tetrahedral or square planar.

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