Spectral characterisation of new organic fluorescent dyes with an alkoxysilane moiety and their utilisation for the labelling of layered silicates

2013 ◽  
Vol 67 (1) ◽  
Author(s):  
Martin Danko ◽  
Matej Mičušík ◽  
Mária Omastová ◽  
Juraj Bujdák ◽  
Dušan Chorvát
Keyword(s):  
Dicarboxylic Acid ◽  
Photoelectron Spectroscopy ◽  
Laser Scanning ◽  
Fluorescent Dyes ◽  
Stokes Shift ◽  
Particle Surface ◽  
Acid Anhydride ◽  
Laser Scanning Microscopy ◽  
Layered Silicates ◽  
Confocal Laser

AbstractNew fluorescence dyes with an alkoxysilane moiety were synthesised by the condensation of 3-(triethoxysilyl)-1-propanamine (3-aminopropyltriethoxysilane) with 4,10-benzothioxanthene-3,1′-dicarboxylic acid anhydride (BTXA) and N,N-dimethylaminonaphthalene-1,8-dicarboxylic acid anhydride (DMANA), which was accompanied by the formation of an imidic bridge. The compounds N-(3-(triethoxysilyl)propyl)-thioxantheno[2,1,9-dej]isoquinoline-1,3-dione (BTX-S) and 4-(N′, N′-dimethyl)-N-(triethoxysilyl)propyl-1,8-naphthalene dicarboxylic acid imide (DMAN-S) were characterised by steady-state and time-resolved fluorescence spectroscopy in chloroform and ethanol. Both conjugates (BTX-S and DMAN-S) exhibited absorption and emission bands in the same region as the un-substituted BTXA and DMANA. An important Stokes shift was observed for DMAN-S in ethanol. A high fluorescence quantum yield was observed for BTX-S in both solvents and for DMAN-S in chloroform. In addition, the newly developed fluorescent silane dyes were covalently attached to the microscopic particles of layered silicates and on the surface of SiO2 wafers as a proof of concept for fluorescence particle (surface) visualisation. The surface wafer modification was precisely characterised by X-ray photoelectron spectroscopy (XPS). Successful covalent linkage onto the particles of layered silicates was proved by confocal laser scanning microscopy technique.

scholarly journals Investigation of Spin Coating Cerium-Doped Hydroxyapatite Thin Films with Antifungal Properties

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 464
Author(s):  
Simona Liliana Iconaru ◽  
Mihai Valentin Predoi ◽  
Patrick Chapon ◽  
Sofia Gaiaschi ◽  
Krzysztof Rokosz ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Spin Coating ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
X Ray ◽  
Antifungal Properties ◽  
Scanning Electron

In this study, the cerium-doped hydroxyapatite (Ca10−xCex(PO4)6(OH)2 with xCe = 0.1, 10Ce-HAp) coatings obtained by the spin coating method were presented for the first time. The stability of the 10Ce-HAp suspension particles used in the preparation of coatings was evaluated by ultrasonic studies, transmission electron microscopy (TEM), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The surface morphology of the 10Ce-HAp coating was studied by SEM and atomic force microscopy (AFM) techniques. The obtained 10Ce-HAp coatings were uniform and without cracks or unevenness. Glow discharge optical emission spectroscopy (GDOES) and X-ray photoelectron spectroscopy (XPS) were used for the investigation of fine chemical depth profiling. The antifungal properties of the HAp and 10Ce-HAp suspensions and coatings were assessed using Candida albicans ATCC 10231 (C. albicans) fungal strain. The quantitative antifungal assays demonstrated that both 10Ce-HAp suspensions and coatings exhibited strong antifungal properties and that they successfully inhibited the development and adherence of C. albicans fungal cells for all the tested time intervals. The scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) visualization of the C. albicans fungal cells adherence to the 10Ce-HAp surface also demonstrated their strong inhibitory effects. In addition, the qualitative assays also suggested that the 10Ce-HAp coatings successfully stopped the biofilm formation.

Confocal Laser Scanning Microscopy of Hamster Cerebellum using FM4-64 as Intracellular Staining

1998 ◽  
Vol 4 (S2) ◽  
pp. 1126-1127
Author(s):  
O. Castejón ◽  
P. Sims
Keyword(s):  
Confocal Laser Scanning Microscopy ◽  
Laser Scanning ◽  
Granular Layer ◽  
Fluorescent Dyes ◽  
Laser Scanning Microscopy ◽  
Climbing Fibers ◽  
Confocal Laser Scanning ◽  
Scanning Microscopy ◽  
Confocal Laser ◽  
Fluorescence Signal

Confocal laser scanning microscopy is an excellent method to study nerve cell morphology and the three-dimensional distribution and interrelationship of dentrites and axons in the central nervous system. The cerebellum has been taking as a model of a gray center.The FM4-64, a member of the family of fluorescent dyes, has been applied to the cerebellar cortex to evaluate its properties as an intracellular stain and intracortical tracer. Slabs of hamster cerebellum,5 mm thick, were incubated in 10,30 and 100 μm solutions of FM4-64 in sodium phosphate buffer and observed in a slow scan confocal laser scanning microscope. Mossy and climbing fibers were traced in the cerebellar white and gray substances .They exhibited high fluorescence signal at the level of myelin sheath.Mossy fibers were identified in the granular layer by their typical rosette formation and dichotomous bifurcation pattern. Climbing fibers bundles were observed crossing the granular layer and giving collateral branches around Golgi cell bodies.

scholarly journals Applicability of Confocal Raman Microscopy to Observe Microstructural Modifications of Cream Cheeses as Influenced by Freezing

Foods ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 679 ◽  
Author(s):  
Marcello Alinovi ◽  
Germano Mucchetti ◽  
Ulf Andersen ◽  
Tijs A. M. Rovers ◽  
Betina Mikkelsen ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Fluorescent Dyes ◽  
Raman Microscopy ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Confocal Raman Microscopy ◽  
Freezing And Thawing ◽  
High Moisture ◽  
Cream Cheese ◽  
Confocal Raman

Confocal Raman microscopy is a promising technique to derive information about microstructure, with minimal sample disruption. Raman emission bands are highly specific to molecular structure and with Raman spectroscopy it is thus possible to observe different classes of molecules in situ, in complex food matrices, without employing fluorescent dyes. In this work confocal Raman microscopy was employed to observe microstructural changes occurring after freezing and thawing in high-moisture cheeses, and the observations were compared to those obtained with confocal laser scanning microscopy. Two commercially available cream cheese products were imaged with both microscopy techniques. The lower resolution (1 µm/pixel) of confocal Raman microscopy prevented the observation of particles smaller than 1 µm that may be part of the structure (e.g., sugars). With confocal Raman microscopy it was possible to identify and map the large water domains formed during freezing and thawing in high-moisture cream cheese. The results were supported also by low resolution NMR analysis. NMR and Raman microscopy are complementary techniques that can be employed to distinguish between the two different commercial formulations, and different destabilization levels.

Interspecies Interactions of Metal-Oxidizing Thermo-Acidophilic Archaea Acidianus and Sulfolobus

2015 ◽  
Vol 1130 ◽  
pp. 105-108 ◽  
Author(s):  
Rui Yong Zhang ◽  
Jing Liu ◽  
Thomas R. Neu ◽  
Qian Li ◽  
Sören Bellenberg ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Laser Scanning ◽  
Fluorescent Dyes ◽  
Mine Drainage ◽  
Cell Attachment ◽  
Thermophilic Bacteria ◽  
Laser Scanning Microscopy ◽  
Physical Contact ◽  
Confocal Laser ◽  
Acidophilic Archaea

Biofilm formation of microorganisms on relevant surfaces is of great importance for biomining and acid mine drainage (AMD). Thermo-acidophilic archaea like Acidianus, Sulfolobus and Metallosphaera are of special interest due to their ability to enhance leaching rates. Visualization and investigation of microbial attachment and biofilm formation of metal-oxidizing organisms up to now has been done mostly with mesophilic or moderately thermophilic bacteria. In this study, attachment and biofilms by the crenarchaeota Sulfolobus metallicus DSM 6482T and a new isolate Acidianus sp. DSM 29099 on sulfur or pyrite were analyzed. Confocal laser scanning microscopy (CLSM) combined with fluorescent dyes specific for nucleic acids or glycoconjugates were used to monitor biofilm formation on surfaces. The data indicate that cell attachment and the subsequently formed biofilm structures were species and substrate dependent. The investigation of binary biofilms on pyrite showed that both species were heterogeneously distributed on pyrite surfaces in the form of individual cells or microcolonies. In addition, physical contact between the two species was visible, as revealed by specific lectins able to distinguish single species.

scholarly journals Antimicrobial Activity Evaluation on Silver Doped Hydroxyapatite/Polydimethylsiloxane Composite Layer

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
C. S. Ciobanu ◽  
A. Groza ◽  
S. L. Iconaru ◽  
C. L. Popa ◽  
P. Chapon ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Photoelectron Spectroscopy ◽  
Laser Scanning ◽  
Composite Layer ◽  
Physicochemical Characterization ◽  
Antimicrobial Effect ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Composite Layers

The goal of this study was the preparation, physicochemical characterization, and microbiological evaluation of novel hydroxyapatite doped with silver/polydimethylsiloxane (Ag:HAp-PDMS) composite layers. In the first stage, the deposition of polydimethylsiloxane (PDMS) polymer layer on commercially pure Si disks has been produced in atmospheric pressure corona discharges. Finally, the new silver doped hydroxyapatite/polydimethylsiloxane composite layer has been obtained by the thermal evaporation technique. The Ag:HAp-PDMS composite layers were characterized by various techniques, such as Scanning Electron Microscopy (SEM), Glow Discharge Optical Emission Spectroscopy (GDOES), and X-ray photoelectron spectroscopy (XPS). The antimicrobial activity of the Ag:HAp-PDMS composite layer was assessed againstCandida albicansATCC 10231 (ATCC—American Type Culture Collection) by culture based and confirmed by SEM and Confocal Laser Scanning Microscopy (CLSM) methods. This is the first study reporting the antimicrobial effect of the Ag:HAp-PDMS composite layer, which proved to be active againstCandida albicansbiofilm embedded cells.

scholarly journals Electrochemical and surface analytical techniques applied to microbiologically influenced corrosion investigation

2018 ◽  
Vol 36 (4) ◽  
pp. 349-363 ◽  
Author(s):  
László Trif ◽  
Abdul Shaban ◽  
Judit Telegdi
Keyword(s):  
Photoelectron Spectroscopy ◽  
Laser Scanning ◽  
Electrochemical Impedance ◽  
Electrochemical Techniques ◽  
Analytical Techniques ◽  
Laser Scanning Microscopy ◽  
Microbiologically Influenced Corrosion ◽  
Microbial Consortia ◽  
Confocal Laser ◽  
The Impact

AbstractSuitable application of techniques for detection and monitoring of microbiologically influenced corrosion (MIC) is crucial for understanding the mechanisms of the interactions and for selecting inhibition and control approaches. This paper presents a review of the application of electrochemical and surface analytical techniques in studying the MIC process of metals and their alloys. Conventional electrochemical techniques, such as corrosion potential (Ecorr), redox potential, dual-cell technique, polarization curves, electrochemical impedance spectroscopy (EIS), electrochemical noise (EN) analysis, and microelectrode techniques, are discussed, with examples of their use in various MIC studies. Electrochemical quartz crystal microbalance, which is newly used in MIC study, is also discussed. Microscopic techniques [scanning electron microscopy (SEM), environmental SEM (ESEM), atomic force microscopy (AFM), confocal laser microscopy (CLM), confocal laser scanning microscopy (CLSM), confocal Raman microscopy] and spectroscopic analytical methods [Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS)] are also highlighted. This review highlights the heterogeneous characteristics of microbial consortia and use of special techniques to study their probable effects on the metal substrata. The aim of this review is to motivate using a combination of new procedures for research and practical measurement and calculation of the impact of MIC and biofilms on metals and their alloys.

Preparation and properties of bamboo/polymer composites enhanced by in situ polymerization of furfuryl alcohol

2019 ◽  
Vol 9 (7) ◽  
pp. 712-722 ◽  
Author(s):  
Yong Wang ◽  
Layun Deng ◽  
Zhihong Xiao ◽  
Xianjun Li ◽  
Youhua Fan ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Furfuryl Alcohol ◽  
Laser Scanning ◽  
In Situ Polymerization ◽  
Decay Resistance ◽  
Laser Scanning Microscopy ◽  
Modulus Of Rupture ◽  
Confocal Laser ◽  
Infrared Spectrometry ◽  
Addition Level

The objective of this paper aimed to develop a novel method to prepare enhanced bamboo-based materials. Furfuryl alcohol (FA) was used as the modification agent with maleic anhydride (MA) as the catalyst. Different bamboo samples were prepared with different FA addition level (10 wt%, 20 wt% and 30 wt%). The furfurylated bamboo samples were characterized by confocal laser scanning microscopy (CLSM), Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). Moreover, the physical and mechanical properties including weight percent gain (WPG), water uptake (WU), thickness swelling (TS), modulus of rupture (MOR), and modulus of elastic (MOE) were investigated in detail. Additionally, the decay resistance of pristine and furfurylated bamboo samples was also investigated. The results showed that FA resins were incorporated into bamboo and polymerized within cell walls. The WPG, WU, and TS were dependent on FA addition level. When the FA addition level reached 30 wt%, the physical properties were all improved significantly. However, due to acidic MA as the catalyst, MOR of furfurylated bamboo samples was enhanced only 2.5% while MOE was weakened. The thermal stability and decay resistance of furfurylated bamboo were all enhanced significantly compared to pristine bamboo. Especially, furfurylated bamboo treated with 30 wt% FA achieved Class I Strong Decay Resistance (<10%) with 5.3% of mass loss.

scholarly journals Sanguinarine Inhibits Mono- and Dual-Species Biofilm Formation by Candida albicans and Staphylococcus aureus and Induces Mature Hypha Transition of C. albicans

2020 ◽  
Vol 13 (1) ◽  
pp. 13 ◽  
Author(s):  
Weidong Qian ◽  
Wenjing Wang ◽  
Jianing Zhang ◽  
Miao Liu ◽  
Yuting Fu ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Laser Scanning ◽  
Inhibitory Concentration ◽  
Fluorescent Dyes ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Matrix Component ◽  
New Agents ◽  
Diffusion Assay ◽  
And Staphylococcus Aureus

Previous studies have reported that sanguinarine possesses inhibitory activities against several microorganisms, but its effects on mono- and dual-species biofilms of C. albicans and S. aureus have not been fully elucidated. In this study, we aimed to evaluate the efficacy of sanguinarine for mono- and dual-species biofilms and explore its ability to induce the hypha-to-yeast transition of C. albicans. The results showed that the minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC90) of sanguinarine against C. albicans and S. aureus mono-species biofilms was 4, and 2 μg/mL, respectively, while the MIC and MBIC90 of sanguinarine against dual-species biofilms was 8, and 4 μg/mL, respectively. The decrease in the levels of matrix component and tolerance to antibiotics of sanguinarine-treated mono- and dual-species biofilms was revealed by confocal laser scanning microscopy combined with fluorescent dyes, and the gatifloxacin diffusion assay, respectively. Meanwhile, sanguinarine at 128 and 256 μg/mL could efficiently eradicate the preformed 24-h biofilms by mono- and dual-species, respectively. Moreover, sanguinarine at 8 μg/mL could result in the transition of C. albicans from the mature hypha form to the unicellular yeast form. Hence, this study provides useful information for the development of new agents to combat mono- and dual-species biofilm-associated infections, caused by C. albicans and S. aureus.

Effect of Exogenous Galactose on EPS Production during Bioleaching of Pyrite by Acidithiobacillus ferrooxidans

2013 ◽  
Vol 825 ◽  
pp. 125-128 ◽  
Author(s):  
Beatriz Pavez ◽  
Albert Saavedra ◽  
Mauricio Diaz ◽  
Juan Carlos Gentina
Keyword(s):  
Laser Scanning ◽  
Extracellular Polymeric Substances ◽  
Control Experiment ◽  
Particle Surface ◽  
Fermentation Medium ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Sulphide Minerals ◽  
Initial Ph ◽  
Shake Flasks

Extracellular polymeric substances (EPS) play an important role in the attachment of bacteria to sulphide minerals, biofilm formation and efficiency of the bioleaching process. Previous studies have suggested a potential connection between galactose and EPS formation. In this context, the influence of exogenous galactose on EPS formation during the bioleaching of pyrite was studied. In order to fully adapt the microorganism to bioleaching conditions it was performed a total of five consecutive sub cultures, one every fifteen days, taking for each one inocula from previous culture in shake flasks with 200 ml of fermentation medium at 30°C, 200 rpm, 40 gL-1 mineral and an initial pH of 1,8. Assays were performed in a medium supplemented with exogenous galactose (0.25% w/v) and without exogenous galactose (control), both with an initial concentration of ferric sulphate in the first three sub cultures of 5 gL-1, decreasing in the last two sub cultures to 2.5 gL-1. Samples of three cultures in both conditions were analyzed using confocal laser scanning microscopy (CLSM) labelling the cells with propidium iodide and EPS carbohydrates with Wheat Germ Agglutinin (WGA). Samples obtained on the last day of the fifth culture showed that the EPS layer on the particle surface was 5.00 μm3/μm2 in the case of the control condition and 6.10 μm3/μm2 when bioleaching was carried out in the presence of exogenous galactose. Also it was observed that in the fifth sub culture the volumetric productivity of total iron in the control experiment was 0.0065 gL-1.h-1 compared with 0.0076 gL-1.h-1 obtained in presence of galactose. The results reveal that the presence of galactose in the bioleaching solution stimulates EPS's formation and apparently also favour the pyrite bioleaching process.

scholarly journals Spitzenkörper Localization and Intracellular Traffic of Green Fluorescent Protein-Labeled CHS-3 and CHS-6 Chitin Synthases in Living Hyphae of Neurospora crassa

2007 ◽  
Vol 6 (10) ◽  
pp. 1853-1864 ◽  
Author(s):  
Meritxell Riquelme ◽  
Salomon Bartnicki-García ◽  
Juan Manuel González-Prieto ◽  
Eddy Sánchez-León ◽  
Jorge A. Verdín-Ramos ◽  
...  
Keyword(s):  
Green Fluorescent Protein ◽  
Neurospora Crassa ◽  
Laser Scanning ◽  
Fluorescent Dyes ◽  
Fluorescent Protein ◽  
Golgi Body ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Chitin Synthases ◽  
Green Fluorescent

ABSTRACT The subcellular location and traffic of two selected chitin synthases (CHS) from Neurospora crassa, CHS-3 and CHS-6, labeled with green fluorescent protein (GFP), were studied by high-resolution confocal laser scanning microscopy. While we found some differences in the overall distribution patterns and appearances of CHS-3-GFP and CHS-6-GFP, most features were similar and were observed consistently. At the hyphal apex, fluorescence congregated into a conspicuous single body corresponding to the location of the Spitzenkörper (Spk). In distal regions (beyond 40 μm from the apex), CHS-GFP revealed a network of large endomembranous compartments that was predominantly comprised of irregular tubular shapes, while some compartments were distinctly spherical. In the distal subapex (20 to 40 μm from the apex), fluorescence was observed in globular bodies that appeared to disintegrate into vesicles as they advanced forward until reaching the proximal subapex (5 to 20 μm from the apex). CHS-GFP was also conspicuously found delineating developing septa. Analysis of fluorescence recovery after photobleaching suggested that the fluorescence of the Spk originated from the advancing population of microvesicles (chitosomes) in the subapex. The inability of brefeldin A to interfere with the traffic of CHS-containing microvesicles and the lack of colocalization of CHS-GFP with the endoplasmic reticulum (ER)-Golgi body fluorescent dyes lend support to the idea that CHS proteins are delivered to the cell surface via an alternative route distinct from the classical ER-Golgi body secretory pathway.

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