Siamo grati alla scienza nucleare di processo Pacific Northwest National Laboratory (PNNL) di iniziativa (NPSI)-fondo laboratorio diretto di ricerca e sviluppo (LDRD) per il supporto. Dr. Sayandev Chatterjee fornito le particelle boehmite sintetizzato. Accesso strumentale è stata fornita attraverso una proposta di utente generale W. R. Wiley Ambientale Molecular Sciences Laboratory (EMSL). EMSL è una struttura di uso scientifico nazionale sponsorizzata dall'ufficio di biologico e ambientale ricerca (BER) a PNNL. PNNL è gestito da Battelle per il DOE sotto contratto DE-AC05-76RL01830.

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P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Environmental+Scanning+Electron+Microscopy+Study+of+Water+in+Carbon+Nanopipes.">Environmental Scanning Electron Microscopy Study of Water in Carbon Nanopipes.</a> Nano Lett. 4 (5), 989-993 (2004).</li><li>Nune, S. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anomalous+water+expulsion+from+carbon-based+rods+at+high+humidity.">Anomalous water expulsion from carbon-based rods at high humidity.</a> Nat Nano. 11 (9), 791-797 (2016).</li><li>Soumya, E. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Scanning Electron Microscopy (SEM) and Environmental SEM: Suitable Tools for Study of Adhesion Stage and Biofilm Formation. , (2012).</li><li>Thiberge, S. 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Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Systems+and+methods+for+analyzing+liquids+under+vacuum.">Systems and methods for analyzing liquids under vacuum.</a> USA patent. , (2011).</li><li>Yang, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+SEM+and+ToF-SIMS+analysis+of+IgG+conjugated+gold+nanoparticles+at+aqueous+surfaces.">In situ SEM and ToF-SIMS analysis of IgG conjugated gold nanoparticles at aqueous surfaces.</a> Surf Interface Anal. 46 (4), 224-228 (2014).</li><li>Liu, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+chemical+probing+of+the+electrode-electrolyte+interface+by+ToF-SIMS.">In situ chemical probing of the electrode-electrolyte interface by ToF-SIMS.</a> Lab Chip. 14 (5), 855-859 (2014).</li><li>Ding, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+Molecular+Imaging+of+the+Biofilm+and+Its+Matrix.">In situ Molecular Imaging of the Biofilm and Its Matrix.</a> Anal Chem. 88 (22), 11244-11252 (2016).</li><li>Hua, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-dimensional+and+three-dimensional+dynamic+imaging+of+live+biofilms+in+a+microchannel+by+time-of-flight+secondary+ion+mass+spectrometry.">Two-dimensional and three-dimensional dynamic imaging of live biofilms in a microchannel by time-of-flight secondary ion mass spectrometry.</a> Biomicrofluidics. 9 (3), 031101 (2015).</li><li>Hua, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemical+imaging+of+molecular+changes+in+a+hydrated+single+cell+by+dynamic+secondary+ion+mass+spectrometry+and+super-resolution+microscopy.">Chemical imaging of molecular changes in a hydrated single cell by dynamic secondary ion mass spectrometry and super-resolution microscopy.</a> Integr Biol. 8 (5), 635-644 (2016).</li><li>Hua, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+molecular+imaging+of+a+hydrated+biofilm+in+a+microfluidic+reactor+by+ToF-SIMS.">In situ molecular imaging of a hydrated biofilm in a microfluidic reactor by ToF-SIMS.</a> Analyst. 139 (7), 1609-1613 (2014).</li><li>Yu, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Capturing+the+transient+species+at+the+electrode-electrolyte+interface+by+in+situ+dynamic+molecular+imaging.">Capturing the transient species at the electrode-electrolyte interface by in situ dynamic molecular imaging.</a> Chem Commun. 52 (73), 10952-10955 (2016).</li><li>Yang, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Making+a+hybrid+microfluidic+platform+compatible+for+in+situ+imaging+by+vacuum-based+techniques.">Making a hybrid microfluidic platform compatible for in situ imaging by vacuum-based techniques.</a> J Vac Sci Technol, A. 29 (6), (2011).</li><li>Yang, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probing+liquid+surfaces+under+vacuum+using+SEM+and+ToF-SIMS.">Probing liquid surfaces under vacuum using SEM and ToF-SIMS.</a> Lab Chip. 11 (15), 2481-2484 (2011).</li><li>Yao, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Switchable+1,8-diazabicycloundec-7-ene+and+1-hexanol+ionic+liquid+analyzed+by+liquid+ToF-SIMS.">Switchable 1,8-diazabicycloundec-7-ene and 1-hexanol ionic liquid analyzed by liquid ToF-SIMS.</a> Surf Sci Spectra. 23 (1), 9-28 (2016).</li><li>Yu, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Capturing+the+transient+species+at+the+electrode-electrolyte+interface+by+in+situ+dynamic+molecular+imaging.">Capturing the transient species at the electrode-electrolyte interface by in situ dynamic molecular imaging.</a> Chem Commun. 52 (73), 10952-10955 (2016).</li><li>Clark, S. B., Buchanan, M., Wilmarth, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Basic Research Needs for Environmental Management. , (2016).</li><li>Mills, O. P., Rose, W. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shape+and+surface+area+measurements+using+scanning+electron+microscope+stereo-pair+images+of+volcanic+ash+particles.">Shape and surface area measurements using scanning electron microscope stereo-pair images of volcanic ash particles.</a> Geosphere. 6, 805-811 (2010).</li><li>Li, S., Jiang, F., Yin, Q., Jin, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Scanning+electron+acoustic+microscopy+of+semiconductor+materials.">Scanning electron acoustic microscopy of semiconductor materials.</a> Solid State Commun. 99 (11), 853-857 (1996).</li><li>Dohnalkova, A. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imaging+Hydrated+Microbial+Extracellular+Polymers:+Comparative+Analysis+by+Electron+Microscopy.">Imaging Hydrated Microbial Extracellular Polymers: Comparative Analysis by Electron Microscopy.</a> Appl Environ Microbiol. 77 (4), 1254-1262 (2011).</li><li>Yu, X. -. Y., Liu, B., Yang, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imaging+liquids+using+microfluidic+cells.">Imaging liquids using microfluidic cells.</a> Microfluid Nanofluid. 15 (6), 725-744 (2013).</li><li>Barshack, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Novel+Method+for+"Wet"+SEM.">A Novel Method for "Wet" SEM.</a> Ultrastruct Pathol. 28 (1), 29-31 (2004).</li><li>Cameron, R. E., Donald, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Minizing+sample+evaporation+in+the+Environmental+Scanning+Microscope.">Minizing sample evaporation in the Environmental Scanning Microscope.</a> J Microsc. (Oxford, U. K.). 173 (3), 227-237 (1994).</li><li>Danilatos, G. 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SEM è una potente tecnica di caratterizzazione delle superfici di materiali organici ed inorganici a livello di nanoscala (nm) con alta risoluzione1. Ad esempio, è ampiamente usato per l'analisi dei campioni solidi e asciutti come materiali geologici a semiconduttore e26 27. Tuttavia, ha limiti nel caratterizzare i campioni liquidi e bagnati a causa dell'incompatibilità di liquido all'interno dell'ambiente altamente aspirato necessaria per microsc...

Microscopio elettronico a scansione (SEM) è stato ampiamente applicato per indagare su una serie di esemplari con la produzione di imaging ad alta risoluzione1. La spettroscopia di raggi x dispersiva di energia (EDX) connessa con il SEM consente la determinazione della composizione elementare1. Tradizionalmente, SEM è applicato per l'imaging di campioni solo asciutti e solidi. Negli ultimi 30 anni, SEM ambientale (ESEM) è stato sviluppato per analizzare i campioni idratati parziali in un vapore ambiente2,3,4,5. Tuttavia, ESEM è in grado di immagine i campioni bagnati, completamente fluidi con alta risoluzione desiderata6. Bagnate le cellule SEM sono state sviluppate anche agli esemplari di immagine bagnato utilizzando SEM7,8; Tuttavia, queste cellule sono state sviluppate principalmente per campioni biologici e retrodiffusa formazione immagine dell'elettrone e sono più accessibili per le applicazioni con quei disegni9,10.
Per affrontare le sfide nell'analizzare vari campioni nel loro ambiente nativo di liquido utilizzando SEM, abbiamo inventato un dispositivo microfluidico compatibile vuoto, sistema per l'analisi a liquido vuoto interfaccia (SALVI), per consentire un'alta risoluzione spaziale secondaria analisi elementare e imaging elettronico (SE) di campioni liquidi utilizzando la modalità high vuoto in SEM. Questa tecnica novella include le seguenti caratteristiche uniche: 1) liquido è sondato direttamente in una piccola apertura di 1-2 µm di diametro; 2) liquido si svolge all'interno del foro dalla tensione superficiale; e 3) SALVI è portatile e può essere adattato a più di una piattaforma analitica11,12,13,14,15,16,17 ,18.
SALVI è costituito da una membrana di nitruro (SiN) di 100 nm silicio di spessore e un microchannel ampia 200 µm in blocco di polidimetilsilossano (PDMS). La finestra di membrana peccato viene applicata per sigillare il microchannel. I dettagli di fabbricazione e le considerazioni di progettazione chiave erano dettagliati in precedenti lavori e brevetti11,19,20. Attualmente, un produttore e distributore leader di approvvigionamento dei materiali di consumo per microscopia ha acquistato la licenza per vendere dispositivi SALVI commercialmente per liquido SEM applicazioni21,22.
Le applicazioni di SALVI in strumenti analitici basati su vuoto sono state dimostrate usando una varietà di soluzioni acquose e le miscele complesse di liquide tra cui biofilm, cellule di mammifero, nanoparticelle ed elettrodo materiali12, 14 , 17 , 20 , 23 , 24. Tuttavia, gran parte del lavoro di cui sopra utilizzati spettrometria di massa di ioni secondari di tempo di volo (ToF-SIMS) come lo strumento di analisi della chiave, quindi l'applicazione del liquido SEM con SALVI non è stato esplorato completamente. In questo lavoro, SALVI è stato utilizzato per studiare le più grandi particelle colloidali non sferica in liquido utilizzando liquido SEM imaging e l'analisi elementare EDX. L'esempio è costituito da particelle di AlOOH sintetizzate presso il nostro laboratorio. Particelle di dimensioni submicrometriche boehmite sono conosciute per esistere in scorie altamente radioattive presso il sito di Hanford. Sono lenti a sciogliere e può causare problemi reologici nel trattamento dei rifiuti. Pertanto, è importante avere la capacità di caratterizzare le particelle boehmite in liquido25. Questo approccio tecnico può essere utilizzato per studiare boehmite in varie condizioni fisico-chimiche per migliorare la comprensione di queste particelle e le proprietà reologiche correlate. Queste particelle sono state utilizzate per illustrare passo passo come applicare SALVI per alto vuoto SEM al fine di studiare le particelle sospese in un liquido. Punti chiave tecniche per l'integrazione di SALVI e SEM e acquisizione dati SEM sono evidenziati all'interno della carta.
Il protocollo prevede la dimostrazione dell'analisi campione liquido utilizzando SALVI e liquido SEM imaging, per coloro che sono interessati ad utilizzare questa tecnica novella in diverse applicazioni di liquido SEM in futuro.

<table><tbody><tr><td>Carbon Coater</td><td>Cressington</td><td>208 Carbon</td><td>It is accompanied with thickness monitor MTM-10.</td></tr><tr><td>SEM</td><td>FEI</td><td>Quanta 3D FEG</td><td>It provides highly resolved scanning electron microscopy and elemental analysis.</td></tr><tr><td>System for Analysis at the Liquid Vacuum Interface (SALVI)</td><td>Pacific Northwest National Laboratory</td><td>N/A</td><td>SALVI is a unique, vacuum compatible microfluidic cell that enables the characterization of the liquid sample using vacuu- based scientific instrument.</td></tr><tr><td>PEEK Union</td><td>Valco</td><td>ZU1TPK</td><td>The polyether ether ketone union is used for connecting the inlet and outlet of SALVI</td></tr><tr><td>Syringe</td><td>BD</td><td>309659</td><td>1 mL</td></tr><tr><td>Pipette</td><td>Thermo Fisher Scientific</td><td>21-377-821</td><td>Range: 100 to 1,000 mL</td></tr><tr><td>Pipette Tip 1</td><td>Neptune</td><td>2112.96.BS</td><td>1,000 &amp;micro;L</td></tr><tr><td>Pipette Tip 2</td><td>Rainin</td><td>17001865</td><td>20 &amp;micro;L</td></tr><tr><td>Syringe Pump</td><td>Harvard Apparatus</td><td>70-2213</td><td>It is used to inject the liquid sample into the SALVI device.</td></tr><tr><td>pH meter</td><td>Fisher Scientific/accumet</td><td>13-636-AP72</td><td>It is used for measuring the pH of AlOOH in DI water.</td></tr><tr><td>Barnstead Ultrapure Water System, UV/UF</td><td>Thermo Scientific Barnstead</td><td>Nanopure diamond D11931</td><td>It is used for producing DI water.</td></tr><tr><td>Centrifuge tubes</td><td>Fisher scientific/Falcon</td><td>15-527-90</td><td>15 mL</td></tr><tr><td>Bransonic ultrasonic cleaner</td><td>Sigma-Aldrich</td><td>2510</td><td>It is used to ultrasonicate the AlOOH liquid sample.</td></tr><tr><td>Balance</td><td>Mettler Toledo</td><td>11106015</td><td>XS64</td></tr><tr><td>AlOOH</td><td>Pacific Northwest National Laboratory</td><td>N/A</td><td>It is synthesized by scientists at Pacific Northwest National Laboratory.</td></tr><tr><td>xT microscope Control</td><td>FEI</td><td>Quanta 3D FEG</td><td>Default microscope control software of SEM Quanta 3D FEG</td></tr><tr><td>EDAX Genesis software</td><td>EDAX</td><td>N/A</td><td>The software is used for collecting the EDX elemental information of the samples.</td></tr><tr><td>Teflon tubing</td><td>SUPELCO</td><td>58697-U</td><td>It is used for introducing the sample into the microchannel and holding adequate volume of liquid.</td></tr></tbody></table>

in situ characterization of boehmite particles in water using liquid sem

In situ un analisi elementale e imaging delle particelle boehmite (AlOOH) in acqua è realizzato utilizzando il sistema per analisi all'interfaccia liquido di vuoto (SALVI) e microscopia elettronica a scansione (SEM). Questo documento descrive il metodo e passi cruciali nell'integrare il vuoto SAVLI compatibile a SEM e ottenere elettroni secondari (SE) immagini di particelle nel liquido in alto vuoto. Spettroscopia di raggi x dispersiva di energia (EDX) viene utilizzata per ottenere analisi elementare delle particelle nel liquido e controllo campioni inclusi acqua deionizzata (DI) solo e anche un canale vuoto. Boehmite sintetizzato (AlOOH) particelle sospese in un liquido sono usate come modello nell'illustrazione liquido SEM. I risultati dimostrano che le particelle possono essere imaged in modalità SE con buona risoluzione (cioè, 400 nm). Lo spettro di AlOOH EDX Mostra segnale significativo dall'alluminio (Al) se confrontato con l'acqua DI ed il controllo di canale vuoto. In situ liquido SEM è una tecnica potente per studiare le particelle nel liquido con molte applicazioni interessanti. Questa procedura mira a fornire il know-how tecnico per condotta liquido SEM imaging e l'analisi EDX utilizzando SALVI e ridurre potenziali problemi quando si utilizza questo approccio.

I risultati rappresentativi vengono presentati per mostrare come le particelle vengono ripresi e analizzati usando in situ liquido imaging SEM accoppiato con EDX. I risultati includono SE immagini e spettri EDX. Le immagini SE sono state ottenute a 100.000 X e 200.000 X ingrandimenti nella Figura 1. Figura 1a raffigura l'immagine SE di AlOOH, Figura 1b DI acqua e Figura ...

Watch this Scientific Journal Video about In Situ Characterization of Boehmite Particles in Water Using Liquid SEM at JoVE.com

In Situ Characterization of Boehmite Particles in Water Using Liquid SEM

In Situ Caratterizzazione delle particelle Boehmite in acqua usando liquido SEM

Presentiamo una procedura per l'analisi di composizione elementare di boehmite particelle in acqua deionizzata e immagini in tempo reale di in situ liquido scansione microscopia elettronica.

In situ imaging and elemental analysis of boehmite (AlOOH) particles in water is realized using the System for Analysis at the Liquid Vacuum Interface ...

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Chemistry

In Situ Characterization of Boehmite Particles in Water Using Liquid SEM

9.2K Views.  Pacific Northwest National Laboratory. Presentiamo una procedura per l'analisi di composizione elementare di boehmite particelle in acqua deionizzata e immagini in tempo reale di in situ liquido scansione microscopia elettronica.

Video: In Situ Characterization of Boehmite Particles in Water Using Liquid SEM

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and detritus, and excreting particulate and dissolved compounds, they serve as important agents for benthic-pelagic coupling. Accurately measuring the compounds removed and excreted by suspension feeders (such as sponges, ascidians, polychaetes, bivalves) is crucial for the study of their physiology, metabolism, and feeding ecology, and is fundamental to determine the ecological relevance of the nutrient fluxes mediated by these organisms. However, the assessment of the rate by which suspension feeders process particulate and dissolved compounds in nature is restricted by the limitations of the currently available methodologies. Our goal was to develop a simple, reliable, and non-intrusive method that would allow clean and controlled water sampling from a specific point, such as the excurrent aperture of benthic suspension feeders, in situ. Our method allows simultaneous sampling of inhaled and exhaled water of the studied organism by using minute tubes installed on a custom-built manipulator device and carefully positioned inside the exhalant orifice of the sampled organism. Piercing a septum on the collecting vessel with a syringe needle attached to the distal end of each tube allows the external pressure to slowly force the sampled water into the vessel through the sampling tube. The slow and controlled sampling rate allows integrating the inherent patchiness in the water while ensuring contamination free sampling. We provide recommendations for the most suitable filtering devices, collection vessel, and storing procedures for the analyses of different particulate and dissolved compounds. The VacuSIP system offers a reliable method for the quantification of undisturbed suspension feeder metabolism in natural conditions that is cheap and easy to learn and apply to assess the physiology and functional role of filter feeders in different ecosystems.

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

We introduce the VacuSIP, a simple, non-intrusive, and reliable method for clean and accurate point sampling of water. The system was developed and evaluated for the simultaneous collection of the water inhaled and exhaled by benthic suspension feeders in situ, to cleanly measure removal and excretion of particulate and dissolved compounds.

VacuSIP, un metodo migliorato per Inex<em&gt; In Situ</em&gt; Misura di particolato e sciolto composti elaborati da Alimentatori sospensioni attive

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and ...

Ricerca

Ambiente

Phase Diagram Characterization Using Magnetic Beads as Liquid Carriers

Magnetic beads with ~1.9 &#181;m average diameter were used to transport microliter volumes of liquids between contiguous liquid segments with a tube for the purpose of investigating phase change of those liquid segments. The magnetic beads were externally controlled using a magnet, allowing for the beads to bridge the air valve between the adjacent liquid segments. A hydrophobic coating was applied to the inner surface of the tube to enhance the separation between two liquid segments. The applied magnetic field formed an aggregate cluster of magnetic beads, capturing a certain liquid amount within the cluster that is referred to as carry-over volume. A fluorescent dye was added to one liquid segment, followed by a series of liquid transfers, which then changed the fluorescence intensity in the neighboring liquid segment. Based on the numerical analysis of the measured fluorescence intensity change, the carry-over volume per mass of magnetic beads has been found to be ~2 to 3 &#181;l/mg. This small amount of liquid allowed for the use of comparatively small liquid segments of a couple hundred microliters, enhancing the feasibility of the device for a lab-in-tube approach. This technique of applying small compositional variation in a liquid volume was applied to analyzing the binary phase diagram between water and the surfactant C12E5 (pentaethylene glycol monododecyl ether), leading to quicker analysis with smaller sample volumes than conventional methods.

Here, we present a protocol to investigate multi-component phase diagrams using externally controlled magnetic beads as liquid carriers in a lab-in-tube approach. This approach can aid in applications that seek to gather further information on phase change in complex liquid systems.

Fase Diagramma Caratterizzazione utilizzando biglie magnetiche come vettori liquidi

Magnetic beads with ~1.9 &#181;m average diameter were used to transport microliter volumes of liquids between contiguous liquid segments with a tube for ...

Ingegneria

In Situ Characterization of Hydrated Proteins in Water by SALVI and ToF-SIMS

This work demonstrates in situ characterization of protein biomolecules in the aqueous solution using the System for Analysis at the Liquid Vacuum Interface (SALVI) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The fibronectin protein film was immobilized on the silicon nitride (SiN) membrane that forms the SALVI detection area. During ToF-SIMS analysis, three modes of analysis were conducted including high spatial resolution mass spectrometry, two-dimensional (2D) imaging, and depth profiling. Mass spectra were acquired in both positive and negative modes. Deionized water was also analyzed as a reference sample. Our results show that the fibronectin film in water has more distinct and stronger water cluster peaks compared to water alone. Characteristic peaks of amino acid fragments are also observable in the hydrated protein ToF-SIMS spectra. These results illustrate that protein molecule adsorption on a surface can be studied dynamically using SALVI and ToF-SIMS in the liquid environment for the first time.

In Situ Characterization of Hydrated Proteins in Water by SALVI and ToF-SIMS

This work presents a protocol for liquid handling and sample introduction to a microchannel for in situ time-of-flight secondary ion mass spectrometry analysis of protein biomolecules in an aqueous solution.

In Situ Caratterizzazione di idrate proteine ​​in acqua da Salvi e TOF-SIMS

This work demonstrates in situ characterization of protein biomolecules in the aqueous solution using the System for Analysis at the Liquid Vacuum ...

Chimica

Nanostructured Ag-zeolite Composites as Luminescence-based Humidity Sensors

Small silver clusters confined inside zeolite matrices have recently emerged as a novel type of highly luminescent materials. Their emission has high external quantum efficiencies (EQE) and spans the whole visible spectrum. It has been recently reported that the UV excited luminescence of partially Li-exchanged sodium Linde type A zeolites [LTA(Na)] containing luminescent silver clusters can be controlled by adjusting the water content of the zeolite. These samples showed a dynamic change in their emission color from blue to green and yellow upon an increase of the hydration level of the zeolite, showing the great potential that these materials can have as luminescence-based humidity sensors at the macro and micro scale. Here, we describe the detailed procedure to fabricate a humidity sensor prototype using silver-exchanged zeolite composites. The sensor is produced by suspending the luminescent Ag-zeolites in an aqueous solution of polyethylenimine (PEI) to subsequently deposit a film of the material onto a quartz plate. The coated plate is subjected to several hydration/dehydration cycles to show the functionality of the sensing film.

A protocol for the synthesis of moisture-responsive luminescent Ag-zeolite composites is described in this report.

Compositi nanostrutturati Ag-zeolite come Sensori di umidità a base di luminescenza

Small silver clusters confined inside zeolite matrices have recently emerged as a novel type of highly luminescent materials. Their emission has high ...

Sub-nanometer Resolution Imaging with Amplitude-modulation Atomic Force Microscopy in Liquid

Atomic force microscopy (AFM) has become a well-established technique for nanoscale imaging of samples in air and in liquid. Recent studies have shown that when operated in amplitude-modulation (tapping) mode, atomic or molecular-level resolution images can be achieved over a wide range of soft and hard samples in liquid. In these situations, small oscillation amplitudes (SAM-AFM) enhance the resolution by exploiting the solvated liquid at the surface of the sample. Although the technique has been successfully applied across fields as diverse as materials science, biology and biophysics and surface chemistry, obtaining high-resolution images in liquid can still remain challenging for novice users. This is partly due to the large number of variables to control and optimize such as the choice of cantilever, the sample preparation, and the correct manipulation of the imaging parameters. Here, we present a protocol for achieving high-resolution images of hard and soft samples in fluid using SAM-AFM on a commercial instrument. Our goal is to provide a step-by-step practical guide to achieving high-resolution images, including the cleaning and preparation of the apparatus and the sample, the choice of cantilever and optimization of the imaging parameters. For each step, we explain the scientific rationale behind our choices to facilitate the adaptation of the methodology to every user's specific system.

We present a method for achieving sub-nanometer resolution images with amplitude-modulation (tapping mode) atomic force microscopy in liquid. The method is demonstrated on commercial atomic force microscopes. We explain the rationale behind our choices of parameters and suggest strategies for resolution optimization.

Sub-nanometrica Resolution Imaging con modulazione di ampiezza in microscopia a forza atomica in Liquid

Atomic force microscopy (AFM) has become a well-established technique for nanoscale imaging of samples in air and in liquid. Recent studies have shown ...

A Facile Synthetic Method to Obtain Bismuth Oxyiodide Microspheres Highly Functional for the Photocatalytic Processes of Water Depuration

Bismuth oxyhalide (BiOI) is a promising material for sunlight-driven-environmental photocatalysis. Given that the physical structure of this kind of materials is highly related to its photocatalytic performance, it is necessary to standardize the synthetic methods in order to obtain the most functional architectures and, thus, the highest photocatalytic efficiency. Here, we report a reliable route to obtain BiOI microspheres via the solvothermal process, using Bi(NO3)3 and potassium iodide (KI) as precursors, and ethylene glycol as a template. The synthesis is standardized in a 150 mL autoclave, at 126 &#176;C for 18 h. This results in 2-3 &#181;m-sized mesoporous microspheres, with a relevant specific surface area (61.3 m2/g). Shortening the reaction times in the synthesis results in amorphous structures, while higher temperatures lead to a slight increase in the porosity of the microspheres, with no effect in the photocatalytic performance. The materials are photo-active under UV-A/visible light irradiation for the degradation of the antibiotic ciprofloxacin in water. This method has demonstrated to be effective in interlaboratory tests, obtaining similar BiOI microspheres in Mexican and Chilean research groups.

This article describes a synthetic method to obtain bismuth oxyiodide microspheres, which are highly functional to perform the photocatalytic removal of organic pollutants, such as ciprofloxacin, in water under UV-A/visible light irradiation.

Un Facile metodo sintetico per ottenere bismuto Oxyiodide microsfere altamente funzionale per i processi fotocatalitici di depurazione delle acque

Bismuth oxyhalide (BiOI) is a promising material for sunlight-driven-environmental photocatalysis. Given that the physical structure of this kind of ...

In situ FTIR Spectroscopy as a Tool for Investigation of Gas/Solid Interaction: Water-Enhanced CO2 Adsorption in UiO-66 Metal-Organic Framework

In situ infrared spectroscopy is an inexpensive, highly sensitive, and selective valuable tool to investigate the interaction of polycrystalline solids with adsorbates. Vibrational spectra provide information on the chemical nature of adsorbed species and their structure. Thus, they are very useful for obtaining molecular level understanding of surface species. The IR spectrum of the sample itself gives some direct information about the material. General conclusions can be drawn concerning hydroxyl groups, some stable surface species and impurities. However, the spectrum of the sample is &#34;blind&#34; with respect to the presence of coordinatively unsaturated ions and gives rather poor information about the acidity of surface hydroxyls, species decisive for the adsorption and catalytic properties of the materials. Furthermore, no discrimination between bulk and surface species can be made. These problems are solved by the use of probe molecules, substances that interact specifically with the surface; the alteration of some spectral features of these molecules as a result of adsorption provides valuable information about the nature, properties, location, concentration, etc., of the surface sites.
The experimental protocol for in-situ IR studies of gas/sample interaction includes preparation of a sample pellet, activation of the material, initial spectral characterization through the analysis of the background spectra, characterization by probe molecules, and study of the interaction with a particular set of gas mixtures. In this paper we investigate a zirconium terephthalate metal organic framework, Zr6O4(OH)4(BDC)6 (BDC = benzene-1,4-dicarboxylate), namely UiO-66 (UiO refers to University of Oslo). The acid sites of the UiO-66 sample are determined by using CO and CD3CN as molecular probes. Furthermore, we have demonstrated that CO2 is adsorbed on basic sites exposed on dehydroxylated UiO-66. Introduction of water to the system produces hydroxyl groups acting as additional CO2 adsorption sites. As a result, CO2 adsorption capacity of the sample is strongly enhanced.

In situ FTIR Spectroscopy as a Tool for Investigation of Gas/Solid Interaction: Water-Enhanced CO2 Adsorption in UiO-66 Metal-Organic Framework

The use of FTIR spectroscopy for investigation of the surface properties of polycrystalline solids is described. Preparation of sample pellets, activation procedures, characterization with probe molecules and model studies of CO2 adsorption are discussed.

In situ Spettroscopia FTIR come strumento per lo studio dell'interazione gas/solido: adsordimento di CO2 potenziato con acqua in UiO-66 Metal-Organic Framework

In situ infrared spectroscopy is an inexpensive, highly sensitive, and selective valuable tool to investigate the interaction of polycrystalline solids ...

Nanoscale Characterization of Liquid-Solid Interfaces by Coupling Cryo-Focused Ion Beam Milling with Scanning Electron Microscopy and Spectroscopy

Physical and chemical processes at solid-liquid interfaces play a crucial role in many natural and technological phenomena, including catalysis, solar energy and fuel generation, and electrochemical energy storage. Nanoscale characterization of such interfaces has recently been achieved using cryogenic electron microscopy, thereby providing a new path to advancing our fundamental understanding of interface processes.
This contribution provides a practical guide to mapping the structure and chemistry of solid-liquid interfaces in materials and devices using an integrated cryogenic electron microscopy approach. In this approach, we pair cryogenic sample preparation which allows stabilization of solid-liquid interfaces with cryogenic focused ion beam (cryo-FIB) milling to create cross-sections through these complex buried structures. Cryogenic scanning electron microscopy (cryo-SEM) techniques performed in a dual-beam FIB/SEM enable direct imaging as well as chemical mapping at the nanoscale. We discuss practical challenges, strategies to overcome them, as well as protocols for obtaining optimal results. While we focus in our discussion on interfaces in energy storage devices, the methods outlined are broadly applicable to a range of fields where solid-liquid interface play a key role.

Cryogenic Focused Ion Beam (FIB) and Scanning Electron Microscopy (SEM) techniques can provide key insights into the chemistry and morphology of intact solid-liquid interfaces. Methods for preparing high quality Energy Dispersive X-ray (EDX) spectroscopic maps of such interfaces are detailed, with a focus on energy storage devices.

Caratterizzazione su scala nanometrica di interfacce liquido-solido mediante accoppiamento di fresatura a fascio ionico crio-focalizzato con microscopia elettronica a scansione e spettroscopia

Physical and chemical processes at solid-liquid interfaces play a crucial role in many natural and technological phenomena, including catalysis, solar ...

Performing In Situ Closed-Cell Gas Reactions in the Transmission Electron Microscope

Gas reactions studied by in situ electron microscopy can be used to capture the real-time morphological and microchemical transformations of materials at length scales down to the atomic level. In situ closed-cell gas reaction (CCGR) studies performed using (scanning) transmission electron microscopy (STEM) can separate and identify localized dynamic reactions, which are extremely challenging to capture using other characterization techniques. For these experiments, we used a CCGR holder that utilizes microelectromechanical systems (MEMS)-based heating microchips (hereafter referred to as &#34;E-chips&#34;). The experimental protocol described here details the method for performing in situ gas reactions in dry and wet gases in an aberration-corrected STEM. This method finds relevance in many different materials systems, such as catalysis and high-temperature oxidation of structural materials at atmospheric pressure and in the presence of various gases with or without water vapor. Here, several sample preparation methods are described for various material form factors. During the reaction, mass spectra obtained with a residual gas analyzer (RGA) system with and without water vapor further validates gas exposure conditions during reactions. Integrating an RGA with an in situ CCGR-STEM system can, therefore, provide critical insight to correlate gas composition with the dynamic surface evolution of materials during reactions. In situ/operando studies using this approach allow&#160;for detailed investigation of the fundamental reaction mechanisms and kinetics that occur at specific environmental conditions (time, temperature, gas, pressure), in real-time, and at high spatial resolution.

Performing In Situ Closed-Cell Gas Reactions in the Transmission Electron Microscope

Here, we present a protocol for performing in situ TEM closed-cell gas reaction experiments while detailing several commonly used sample preparation methods.

Esecuzione di reazioni di gas a celle chiuse in situ nel microscopio elettronico a trasmissione

Gas reactions studied by in situ electron microscopy can be used to capture the real-time morphological and microchemical transformations of materials at ...

Characterization of Calcification Events Using Live Optical and Electron Microscopy Techniques in a Marine Tubeworm

Characterizing the first event of biological production of calcium carbonate requires a combination of microscopy approaches. First, intracellular pH distribution and calcium ions can be observed using live microscopy over time. This allows identification of the life stage and the tissue with the feature of interest for further electron microscopy studies. Life stage and tissues of interest are typically higher in pH and Ca signals. 
Here, using H. elegans, we present a protocol to characterize the presence of calcium carbonate structures in a biological specimen on the scanning electron microscope (SEM), using energy-dispersive X-ray spectroscopy (EDS) to visualize elemental composition, using electron backscatter diffraction (EBSD) to determine the presence of crystalline structures, and using transmission electron microscopy (TEM) to analyze the composition and structure of the material. In this protocol, a focused ion beam (FIB) is used to isolate samples with dimension suitable for TEM analysis. As FIB is a site specific technique, we demonstrate how information from the previous techniques can be used to identify the region of interest, where Ca signals are highest.

We demonstrate the use of various microscopy methods that are useful in observing the calcification of a tubeworm, Hydroides elegans, as well as locating and characterizing the first calcified material. Live microscopy and electron microscopy are used together to provide functional and material information that are important in studying biomineralization.

Caratterizzazione di calcificazione eventi utilizzando dal vivo ottica ed elettronica Microscopia tecniche in un tubeworm Marine

Characterizing the first event of biological production of calcium carbonate requires a combination of microscopy approaches. First, intracellular pH ...

In Situ Caratterizzazione delle particelle Boehmite in acqua usando liquido SEM

Riepilogo

Esplora Altri Video

Capitoli in questo video

VacuSIP, un metodo migliorato per Inex

Fase Diagramma Caratterizzazione utilizzando biglie magnetiche come vettori liquidi

In Situ Caratterizzazione di idrate proteine in acqua da Salvi e TOF-SIMS

Compositi nanostrutturati Ag-zeolite come Sensori di umidità a base di luminescenza

Sub-nanometrica Resolution Imaging con modulazione di ampiezza in microscopia a forza atomica in Liquid

Un Facile metodo sintetico per ottenere bismuto Oxyiodide microsfere altamente funzionale per i processi fotocatalitici di depurazione delle acque

In situ Spettroscopia FTIR come strumento per lo studio dell'interazione gas/solido: adsordimento di CO₂ potenziato con acqua in UiO-66 Metal-Organic Framework

Caratterizzazione su scala nanometrica di interfacce liquido-solido mediante accoppiamento di fresatura a fascio ionico crio-focalizzato con microscopia elettronica a scansione e spettroscopia

Esecuzione di reazioni di gas a celle chiuse in situ nel microscopio elettronico a trasmissione

Caratterizzazione di calcificazione eventi utilizzando dal vivo ottica ed elettronica Microscopia tecniche in un tubeworm Marine

In Situ Caratterizzazione delle particelle Boehmite in acqua usando liquido SEM

Riepilogo

Esplora Altri Video

Capitoli in questo video

VacuSIP, un metodo migliorato per Inex

Fase Diagramma Caratterizzazione utilizzando biglie magnetiche come vettori liquidi

In Situ Caratterizzazione di idrate proteine ​​in acqua da Salvi e TOF-SIMS

Compositi nanostrutturati Ag-zeolite come Sensori di umidità a base di luminescenza

Sub-nanometrica Resolution Imaging con modulazione di ampiezza in microscopia a forza atomica in Liquid

Un Facile metodo sintetico per ottenere bismuto Oxyiodide microsfere altamente funzionale per i processi fotocatalitici di depurazione delle acque

In situ Spettroscopia FTIR come strumento per lo studio dell'interazione gas/solido: adsordimento di CO2 potenziato con acqua in UiO-66 Metal-Organic Framework

Caratterizzazione su scala nanometrica di interfacce liquido-solido mediante accoppiamento di fresatura a fascio ionico crio-focalizzato con microscopia elettronica a scansione e spettroscopia

Esecuzione di reazioni di gas a celle chiuse in situ nel microscopio elettronico a trasmissione

Caratterizzazione di calcificazione eventi utilizzando dal vivo ottica ed elettronica Microscopia tecniche in un tubeworm Marine

In Situ Caratterizzazione di idrate proteine in acqua da Salvi e TOF-SIMS

In situ Spettroscopia FTIR come strumento per lo studio dell'interazione gas/solido: adsordimento di CO₂ potenziato con acqua in UiO-66 Metal-Organic Framework