Vorremmo ringraziare il Dr. Jonathan Newland per la fotografia a figura 4B e per l&#39;elaborazione di immagini al microscopio ottico per il video, la signorina Jennifer Webb per la consulenza e le immagini su misure di angolo di contatto, la signorina Sze-yin Tan per la finestra del solvente dati della figura 2B , il dottor Joseph Maxim per consigli sulla spettroscopia Raman, e anche i membri della Warwick Elettrochimica e interfacce Gruppo che hanno contribuito a sviluppare i protocolli descritti nel presente documento. Vorremmo anche ringraziare Max Joseph, Lingcong Meng, Zoe Ayres e Roy Meyler per la loro parte nella riprese del protocollo.

The authors declare that they have no competing financial interests.

Partendo da una superficie O-terminato è sostenuto perché la superficie H-terminato è elettrochimicamente instabile, soprattutto alle alte potenziali anodici 7,40,41. Cambiare terminazione superficie può influenzare la cinetica di trasferimento elettronico di coppie sfera interiore, come l&#39;elettrolisi dell&#39;acqua (qui utilizzato per modificare il pH della soluzione locale). Inoltre, se il BDD contiene significativa NDC al bordo dei grani è anche possibile che in seguito all&#39;applicazione del es...

Scelta del materiale degli elettrodi è di grande importanza per lo svolgimento di qualsiasi studio elettroanalitica. Negli ultimi anni, sp 3 del carbonio (diamante) drogato con boro sufficiente a rendere il materiale &quot;metal-like&quot; è diventato una scelta popolare per una vasta gamma di applicazioni elettroanalitiche grazie alla sua eccellente elettrochimica (e termiche e meccaniche) proprietà 1,2 , 3. Questi includono la resistenza alla corrosione sotto soluzione, temperatura e pressione estreme 4 finestre solvente ultra-larga e bassa sfondo correnti, e ridotto sporcamento, rispetto ad altri materiali elettrodici comunemente usati 5-7,3. Tuttavia, l&#39;aumento non-diamante-carbonio (NDC: sp 2) Opere risultati in una finestra di solvente in diminuzione, l&#39;aumento delle correnti di fondo 7,8, cambiamenti sia l&#39;integrità strutturale e la sensibilità verso diverse specie redox sfera interiore, ad esempio. ossigeno 9-12. Nota per cosìmi applicazioni, presenza NDC è visto come vantaggioso 13. Inoltre, se il materiale non contiene boro sufficiente si comporterà come p-tipo semiconduttore e mostra una ridotta sensibilità alle specie redox nella finestra potenziale riduttivo, dove il materiale è più impoverito di portatori di carica 7. Infine, la chimica superficiale del boro diamante drogato (BDD) può anche giocare un ruolo nella risposta elettrochimica osservata. Questo è particolarmente vero per le specie a sfera interna che sono sensibili alla superficie chimica e abbassare diamante drogato dove un idrogeno (H -) - superficie chiuso possa far apparire un elettrodo BDD semiconduttore &quot;metal-like&quot; 7. Per sfruttare le proprietà superiori di BDD, è spesso necessario il materiale è sufficientemente drogato e contiene il meno possibile NDC. A seconda del metodo adottato per far crescere il BDD, le proprietà possono variare 14,15. Questo documento suggerisce primo un materiale e di un elettorochemical Guida protocollo di caratterizzazione per la valutazione BDD elettrodo idoneità prima dell&#39;uso (cioè boro sufficiente, minimo NDC) e poi descrive una applicazione basata sul cambiamento localmente pH elettrochimica tramite l&#39;elettrodo protocollo verificata. Questo processo sfrutta la resistenza superficiale del NDC-libera BDD verso corrosione o la dissoluzione sotto il controllo di potenziali estreme applicato (o correnti) per lunghi periodi di tempo. In particolare l&#39;uso di un elettrodo BDD per generare protone stabile (H +) o idrossido (OH -) fondenti causa dell&#39;elettrolisi (ossidazione o riduzione rispettivamente) di acqua in prossimità di un secondo (sensore) 16,17 è descritto qui. In questo modo è possibile controllare l&#39;ambiente pH del sensore in modo sistematico, ad esempio per esperimenti di titolazione pH, o per fissare il pH ad un valore in cui il processo elettrochimico è più sensibile. Quest&#39;ultimo è particolarmente utile perapplicazioni in cui il sensore è posto alla fonte, ad esempio fiume, mare e il pH del sistema non è ottimale per la misura elettrochimica di interesse. Due esempi recenti comprendono: (i) generazione di un basso pH localizzata, in una soluzione a pH neutro, per l&#39;elettrodeposizione e stripping di mercurio 17; notare BDD è un materiale preferito per elettrodeposizione di metalli grazie alla finestra catodica estesa 9,18,19. (ii) La quantificazione della forma elettrochimicamente rilevabile di solfuro di idrogeno, presente a pH elevato, aumentando localmente il pH da neutro a fortemente alcalina 16.

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			<td height="20" style="height:20px;width:117px;">Pt Wire</td>
			<td style="width:64px;"></td>
			<td style="width:75px;"></td>
			<td style="width:117px;">Counter Electrode</td>
		</tr>
		<tr height="100">
			<td height="100" style="height:100px;width:117px;">Saturated Calomel Electrode</td>
			<td style="width:64px;">IJ Cambria Scientific Ltd.</td>
			<td style="width:75px;">2056</td>
			<td style="width:117px;">Reference Electrode (alternatively use Ag|AgCl)</td>
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		<tr height="40">
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			<td style="width:64px;"></td>
			<td style="width:75px;"></td>
			<td style="width:117px;">Working Electrode</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:117px;">Iridium Tetrachloride</td>
			<td style="width:64px;">VWR International Ltd</td>
			<td style="width:75px;">12184.01</td>
			<td style="width:117px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:117px;">Hydrogen Peroxide</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">H1009</td>
			<td style="width:117px;">(30% w/w) Corrosive</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:117px;">Oxalic Acid&#160;</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">241172</td>
			<td style="width:117px;">Harmful, Irritant</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:117px;">Anhydrous Potassium Chloride</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">451029</td>
			<td style="width:117px;"></td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:117px;">Sulphuric Acid</td>
			<td style="width:64px;">VWR International Ltd</td>
			<td style="width:75px;">102765G</td>
			<td style="width:117px;">(98%) Corrosive</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:117px;">Potassium Nitrate</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">221295</td>
			<td style="width:117px;"></td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:117px;">Hexaamine Ruthenium Chloride</td>
			<td style="width:64px;">Strem Chemicals Inc.</td>
			<td style="width:75px;">44-0620</td>
			<td style="width:117px;">Irritant</td>
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		<tr height="40">
			<td height="40" style="height:40px;width:117px;">Perchloric Acid</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">311421</td>
			<td style="width:117px;">Oxidising, Corrosive</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:117px;">2-Propanol</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">24137</td>
			<td style="width:117px;">Flammable</td>
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		<tr height="40">
			<td height="40" style="height:40px;width:117px;">Nitric Acid</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">695033</td>
			<td style="width:117px;">Oxidising, Corrosive</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:117px;">Sputter/ Evapourator</td>
			<td style="width:64px;"></td>
			<td style="width:75px;"></td>
			<td style="width:117px;">With Ti &#38; Au targets</td>
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		<tr height="20">
			<td height="20" style="height:20px;width:117px;">Raman</td>
			<td style="width:64px;"></td>
			<td style="width:75px;"></td>
			<td style="width:117px;">514.5 nm laser</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:117px;">Annealing Oven</td>
			<td style="width:64px;"></td>
			<td style="width:75px;"></td>
			<td style="width:117px;">Capable of 400&#176;C</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:117px;">Ag paste</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">735825</td>
			<td style="width:117px;">or other conductive paint</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:117px;">Potentiostat</td>
			<td style="width:64px;"></td>
			<td style="width:75px;"></td>
			<td style="width:117px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:117px;">pH Buffer solutions</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">38740-38752</td>
			<td style="width:117px;">Fixanal buffer concentrates</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:117px;">Phenolphthalein Indicator</td>
			<td style="width:64px;">VWR International Ltd</td>
			<td style="width:75px;">210893Q</td>
			<td style="width:117px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:117px;">Methyl Red Indicator</td>
			<td style="width:64px;">Sigma-Aldrich</td>
			<td style="width:75px;">32654</td>
			<td style="width:117px;"></td>
		</tr>
	</tbody>
</table>

assessment of boron doped diamond electrode quality and application to in situ modification of local ph by water electrolysis

Boron diamante drogato (BDD) elettrodi hanno dimostrato molto promettente come materiale degli elettrodi dove molte delle loro proprietà riportate come esteso finestra solvente, basse correnti di fondo, resistenza alla corrosione, ecc, derivano dalla natura cataliticamente inerte della superficie. Tuttavia, se durante il processo di crescita, non-diamante-carbonio (NDC) viene incorporato nella matrice elettrodi, le proprietà elettrochimiche cambiano mentre la superficie diventa più cataliticamente attivo. Come tale, è importante che la elettrochimico è consapevole della qualità e conseguente principali proprietà elettrochimiche dell&#39;elettrodo BDD prima dell&#39;uso. Questo articolo descrive una serie di fasi di caratterizzazione, tra cui la microscopia Raman, capacità, finestra solvente e redox elettrochimica, per accertare se l&#39;elettrodo BDD contiene trascurabile NDC e quindi trascurabile sp 2 di carbonio. Un&#39;applicazione è evidenziato che sfrutta il cataliticamente inertee la natura resistente alla corrosione di una superficie NDC privo cioè protoni locale stabile e quantificabile e la produzione di idrossido causa di elettrolisi dell&#39;acqua ad un elettrodo di BDD. Un approccio per misurare la variazione del pH locale indotta mediante elettrolisi dell&#39;acqua utilizzando ossido di iridio elettrodi rivestiti BDD è anche descritto in dettaglio.

Raman spettri ed elettrochimici caratteristiche sono state ottenute per rappresentativi elettrodi macrodisc BDD con diverse densità drogante, ed entrambi i livelli significativi e trascurabili di NDC, figure 1 e 2. Figure 1A e B mostrano dati tipici Raman per NDC contenenti film sottile microcristallina BDD e grano più grande autoportante BDD, drogato sopra della soglia metallica, rispettivamente. La presenza di NDC è...

Watch this Scientific Journal Video about Assessment of Boron Doped Diamond Electrode Quality and Application to In Situ Modification of Local pH by Water Electrolysis at JoVE.com

Assessment of Boron Doped Diamond Electrode Quality and Application to In Situ Modification of Local pH by Water Electrolysis

Un protocollo è descritto per la caratterizzazione dei parametri chiave elettrochimici di boro diamante drogato (BDD) elettrodo e la successiva domanda di esperimenti in situ generazione pH.

Valutazione del Boro Doped Diamante elettrodi Qualità e applicazioni per<em&gt; In Situ</em&gt; Modifica del pH locale da acqua Elettrolisi

Boron doped diamond (BDD) electrodes have shown considerable promise as an electrode material where many of their reported properties such as extended ...

assessment-boron-doped-diamond-electrode-quality-application-to-situ

Research

JoVE Journal

Chemistry

Assessment of Boron Doped Diamond Electrode Quality and Application to In Situ Modification of Local pH by Water Electrolysis

14.7K Views.  University of Warwick.  Un protocollo è descritto per la caratterizzazione dei parametri chiave elettrochimici di boro diamante drogato (BDD) elettrodo e la successiva domanda di esperimenti in situ generazione pH. 

Video: Assessment of Boron Doped Diamond Electrode Quality and Application to In Situ Modification of Local pH by Water Electrolysis

Synthesis, Cellular Delivery and In vivo Application of Dendrimer-based pH Sensors

The development of fluorescent indicators represented a revolution for life sciences. Genetically encoded and synthetic fluorophores with sensing abilities allowed the visualization of biologically relevant species with high spatial and temporal resolution. Synthetic dyes are of particular interest thanks to their high tunability and the wide range of measureable analytes. However, these molecules suffer several limitations related to small molecule behavior (poor solubility, difficulties in targeting, often no ratiometric imaging allowed). In this work we introduce the development of dendrimer-based sensors and present a procedure for pH measurement in vitro, in living cells and in vivo. We choose dendrimers as ideal platform for our sensors for their many desirable properties (monodispersity, tunable properties, multivalency) that made them a widely used scaffold for several biomedical devices. The conjugation of fluorescent pH indicators to the dendrimer scaffold led to an enhancement of their sensing performances. In particular dendrimers exhibit reduced cell leakage, improved intracellular targeting and allow ratiometric measurements. These novel sensors were successfully employed to measure pH in living HeLa cells and in vivo in mouse brain.

Synthesis, Cellular Delivery and In vivo Application of Dendrimer-based pH Sensors

Fluorescence sensors are powerful tools in life science. Here we describe a methodology to synthesize and use dendrimer-based fluorescent sensors to measure pH in living cells and in vivo. The dendritic scaffold enhances the properties of conjugated fluorescent dyes leading to improved sensing properties.

Sintesi, Consegna Cellulare e<em&gt; In vivo</em&gt; Applicazione di sensori di pH basati Dendrimero

The development of  fluorescent indicators represented a revolution for life sciences. Genetically  encoded and synthetic fluorophores with sensing ...

Ricerca

Chimica

Synthesis of Non-uniformly Pr-doped SrTiO3 Ceramics and Their Thermoelectric Properties

We demonstrate a novel synthesis strategy for the preparation of Pr-doped SrTiO3 ceramics via a combination of solid state reaction and spark plasma sintering techniques. Polycrystalline ceramics possessing a unique morphology can be achieved by optimizing the process parameters, particularly spark plasma sintering heating rate. The phase and morphology of the synthesized ceramics were investigated in detail using X-ray diffraction, scanning electron microcopy and energy-dispersive X-ray spectroscopy. It was observed that the grains of these bulk Pr-doped SrTiO3 ceramics were enhanced with Pr-rich grain boundaries. Electronic and thermal transport properties were also investigated as a function of temperature and doping concentration. Such a microstructure was found to give rise to improved thermoelectric properties. Specifically, it resulted in a significant improvement in carrier mobility and the thermoelectric power factor. Simultaneously, it also led to a marked reduction in the thermal conductivity. As a result, a significant improvement (> 30%) in the thermoelectric figure of merit was achieved for the whole temperature range over all previously reported maximum values for SrTiO3-based ceramics. This synthesis demonstrates the steps for the preparation of bulk polycrystalline ceramics of non-uniformly Pr-doped SrTiO3.

Synthesis of Non-uniformly Pr-doped SrTiO3 Ceramics and Their Thermoelectric Properties

A protocol for the synthesis and processing of polycrystalline SrTiO3 ceramics doped non-uniformly with Pr is presented along with the investigation of their thermoelectric properties.

Sintesi di non-uniforme Pr-drogato SrTiO<sub&gt; 3</sub&gt; Ceramica e le loro proprietà termoelettriche

We demonstrate a novel synthesis strategy for the preparation of Pr-doped SrTiO3 ceramics via a combination of solid state reaction and spark plasma ...

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 ...

In Situ Characterization of Shewanella oneidensis MR1 Biofilms by SALVI and ToF-SIMS

Bacterial biofilms are surface-associated communities that are vastly studied to understand their self-produced extracellular polymeric substances (EPS) and their roles in environmental microbiology. This study outlines a method to cultivate biofilm attachment to the System for Analysis at the Liquid Vacuum Interface (SALVI) and achieve in situ chemical mapping of a living biofilm by time-of-flight secondary ion mass spectrometry (ToF-SIMS). This is done through the culturing of bacteria both outside and within the SALVI channel with our specialized setup, as well as through optical imaging techniques to detect the biofilm presence and thickness before ToF-SIMS analysis. Our results show the characteristic peaks of the Shewanella biofilm in its natural hydrated state, highlighting upon its localized water cluster environment, as well as EPS fragments, which are drastically different from the same biofilm's dehydrated state. These results demonstrate the breakthrough capability of SALVI that allows for in situ biofilm imaging with a vacuum-based chemical imaging instrument.

In Situ Characterization of Shewanella oneidensis MR1 Biofilms by SALVI and ToF-SIMS

This article presents a method for growing a biofilm for in situ time-of-flight secondary ion mass spectrometry for chemical mapping in its hydrated state, enabled by a microfluidic reactor, System for Analysis at the liquid Vacuum Interface. The Shewanella oneidensis MR-1 with green fluorescence protein was used as a model.

In Situ Caratterizzazione di Shewanella oneidensis MR1 biofilm di SALVI e ToF-SIMS

Bacterial biofilms are surface-associated communities that are vastly studied to understand their self-produced extracellular polymeric substances (EPS) ...

In Situ Characterization of Boehmite Particles in Water Using Liquid SEM

In situ imaging and elemental analysis of boehmite (AlOOH) particles in water is realized using the System for Analysis at the Liquid Vacuum Interface (SALVI) and Scanning Electron Microscopy (SEM). This paper describes the method and key steps in integrating the vacuum compatible SAVLI to SEM and obtaining secondary electron (SE) images of particles in liquid in high vacuum. Energy dispersive x-ray spectroscopy (EDX) is used to obtain elemental analysis of particles in liquid and control samples including deionized (DI) water only and an empty channel as well. Synthesized boehmite (AlOOH) particles suspended in liquid are used as a model in the liquid SEM illustration. The results demonstrate that the particles can be imaged in the SE mode with good resolution (i.e., 400 nm). The AlOOH EDX spectrum shows significant signal from the aluminum (Al) when compared with the DI water and the empty channel control. In situ liquid SEM is a powerful technique to study particles in liquid with many exciting applications. This procedure aims to provide technical know-how in order to conduct liquid SEM imaging and EDX analysis using SALVI and to reduce potential pitfalls when using this approach.

In Situ Characterization of Boehmite Particles in Water Using Liquid SEM

We present a procedure for real-time imaging and elemental composition analysis of boehmite particles in deionized water by in situ liquid Scanning Electron Microscopy.

In Situ Caratterizzazione delle particelle Boehmite in acqua usando liquido SEM

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

Microfluidic Dry-spinning and Characterization of Regenerated Silk Fibroin Fibers

The protocol demonstrates a method for mimicking the spinning process of silkworm. In the native spinning process, the contracting spinning duct enables the silk proteins to be compact and ordered by shearing and elongation forces. Here, a biomimetic microfluidic channel was designed to mimic the specific geometry of the spinning duct of the silkworm. Regenerated silk fibroin (RSF) spinning doped with high concentration, was extruded through the microchannel to dry-spin fibers at ambient temperature and pressure. In the post-treated process, the as-spun fibers were drawn and stored in ethanol aqueous solution. Synchrotron radiation wide-angle X-ray diffraction (SR-WAXD) technology was used to investigate the microstructure of single RSF fibers, which were fixed to a sample holder with the RSF fiber axis normal to the microbeam of the X-ray. The crystallinity, crystallite size, and crystalline orientation of the fiber were calculated from the WAXD data. The diffraction arcs near the equator of the two-dimensional WAXD pattern indicate that the post-treated RSF fiber has a high orientation degree.

A protocol for the microfluidic spinning and microstructure characterization of regenerated silk fibroin monofilament is presented.

A secco microfluidic-spinning e caratterizzazione delle fibre rigenerate seta Fibroin

The protocol demonstrates a method for mimicking the spinning process of silkworm. In the native spinning process, the contracting spinning duct enables ...

Synthesis of Core-shell Lanthanide-doped Upconversion Nanocrystals for Cellular Applications

Lanthanide-doped upconversion nanocrystals (UCNs) have attracted much attention in recent years based on their promising and controllable optical properties, which allow for the absorption of near-infrared (NIR) light and can subsequently convert it into multiplexed emissions that span over a broad range of regions from the UV to the visible to the NIR. This article presents detailed experimental procedures for high-temperature co-precipitation synthesis of core-shell UCNs that incorporate different lanthanide ions into nanocrystals for efficiently converting deep-tissue penetrable NIR excitation (808 nm) into a strong blue emission at 480 nm. By controlling the surface modification with biocompatible polymer (polyacrylic acid, PAA), the as-prepared UCNs acquires great solubility in buffer solutions. The hydrophilic nanocrystals are further functionalized with specific ligands (dibenzyl cyclooctyne, DBCO) for localization on the cell membrane. Upon NIR light (808 nm) irradiation, the upconverted blue emission can effectively activate the light-gated channel protein on the cell membrane and specifically regulate the cation (e.g., Ca2+) influx in the cytoplasm. This protocol provides a feasible methodology for the synthesis of core-shell lanthanide-doped UCNs and subsequent biocompatible surface modification for further cellular applications.

A protocol is presented for the synthesis of core-shell lanthanide-doped upconversion nanocrystals (UCNs) and their cellular applications for channel protein regulation upon near-infrared (NIR) light illumination.

Sintesi di nanocristalli di Upconversion drogato con lantanidi Core-shell per applicazioni cellulari

Lanthanide-doped upconversion nanocrystals (UCNs) have attracted much attention in recent years based on their promising and controllable optical ...

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

The use of nanoprobes such as gold, silver, silica or iron-oxide nanoparticles as detection reagents in bioanalytical assays can enable high sensitivity and convenient colorimetric readout. However, high densities of nanoparticles are typically needed for detection. The available synthesis-based enhancement protocols are either limited to gold and silver nanoparticles or rely on precise enzymatic control and optimization. Here, we present a protocol to enhance the colorimetric readout of gold, silver, silica, and iron oxide nanoprobes. It was observed that the colorimetric signal can be improved by up to a 10000-fold factor. The basis for such signal enhancement strategies is the chemical reduction of Au3+ to Au0. There are several chemical reactions that enable the reduction of Au3+ to Au0. In the protocol, Good&#39;s buffers and H2O2 are used and it is possible to favor the deposition of Au0 onto the surface of existing nanoprobes, in detriment of the formation of new gold nanoparticles. The protocol consists of the incubation of the microarray with a solution consisting of chloroauric acid and H2O2 in 2-(N-morpholino)ethanesulfonic acid pH 6 buffer following the nanoprobe-based detection assay. The enhancement solution can be applied to paper and glass-based sensors. Moreover, it can be used in commercially available immunoassays as demonstrated by the application of the method to a commercial allergen microarray. The signal development requires less than 5 min of incubation with the enhancement solution and the readout can be assessed by naked eye or low-end image acquisition devices such as a table-top scanner or a digital camera.

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

In this work, a protocol for signal enhancement of nanoprobe-based biosensing is presented. The protocol is based on the reduction of chloroauric acid onto the surface of existing nanoprobes that consist of gold, silver, silica or iron-oxide nanoparticles.

Segnale Nanosonda rapido aumento di sintesi di nanoparticelle di oro In Situ

The use of nanoprobes such as gold, silver, silica or iron-oxide nanoparticles as detection reagents in bioanalytical assays can enable high sensitivity ...

In Situ Lithiated Reference Electrode: Four Electrode Design for In-operando Impedance Spectroscopy

Extending operating voltage of Li-ion batteries results in higher energy output from these devices. High voltages, however, may trigger or accelerate multiple processes responsible for long-term performance decay. Given the complexity of physical processes occurring inside the cell, it is often challenging to achieve a full understanding of the root causes of this performance degradation. This difficulty arises in part from the fact that any electrochemical measurement of a battery will return the combined contributions of all components in the cell. Incorporation of a reference electrode can solve part of the problem, as it allows the electrochemical reactions of the cathode and the anode to be individually probed. A variation in the voltage range experienced by the cathode, for example, can indicate alterations in the pool of cyclable lithium ions in the full-cell. The structural evolution of the many interphases existing in the battery can also be monitored, by measuring the contributions of each electrode to the overall cell impedance. Such wealth of information amplifies the reach of diagnostic analysis in Li-ion batteries and provides valuable input to the optimization of individual cell components. In this work, we introduce the design of a test cell able to accommodate multiple reference electrodes, and present reference electrodes that are appropriate for each specific type of measurement, detailing the assembly process in order to maximize the accuracy of the experimental results.

The incorporation of reference electrodes in a Li-ion battery provides valuable information to elucidate degradation mechanisms at high voltages. In this article, we present a cell design that accommodates multiple reference electrodes, along with the assembly steps to assure maximum accuracy of the data obtained in electrochemical measurements.

In Situ litiati riferimento elettrodo: Elettrodo quattro Design per spettroscopia di impedenza nel operando

Extending operating voltage of Li-ion batteries results in higher energy output from these devices. High voltages, however, may trigger or accelerate ...

Negative Additive Manufacturing of Complex Shaped Boron Carbides

Boron carbide (B4C) is one of the hardest materials in existence. However, this attractive property also limits its machineability into complex shapes for high wear, high hardness, and lightweight material applications such as armors. To overcome this challenge, negative additive manufacturing (AM) is employed to produce complex geometries of boron carbides at various length scales. Negative AM first involves gelcasting a suspension into a 3D-printed plastic mold. The mold is then dissolved away, leaving behind a green body as a negative copy. Resorcinol-formaldehyde (RF) is used as a novel gelling agent because unlike traditional hydrogels, there is little to no shrinkage, which allows for extremely complex molds to be used. Furthermore, this gelling agent can be pyrolyzed to leave behind ~50 wt% carbon, which is a highly effective sintering aid for B4C. Due to this highly homogenous distribution of in situ carbon within the B4C matrix, less than 2% porosity can be achieved after sintering. This protocol highlights in detail the methodology for creating near fully dense boron carbide parts with highly complex geometries.

A method called negative additive manufacturing is used to produce near fully dense complex shaped boron carbide parts of various length scales. This technique is possible via the formulation of a novel suspension involving resorcinol-formaldehyde as a unique gelling agent that leaves behind a homogenous carbon sintering aid after pyrolysis.

Produzione additiva negativa del complesso a forma di carburi di boro

Boron carbide (B4C) is one of the hardest materials in existence. However, this attractive property also limits its machineability into complex shapes for ...

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In Situ litiati riferimento elettrodo: Elettrodo quattro Design per spettroscopia di impedenza nel operando

Produzione additiva negativa del complesso a forma di carburi di boro

Valutazione del Boro Doped Diamante elettrodi Qualità e applicazioni per

Riepilogo

Esplora Altri Video

Capitoli in questo video

Sintesi, Consegna Cellulare e

Sintesi di non-uniforme Pr-drogato SrTiO

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

In Situ Caratterizzazione di Shewanella oneidensis MR1 biofilm di SALVI e ToF-SIMS

In Situ Caratterizzazione delle particelle Boehmite in acqua usando liquido SEM

A secco microfluidic-spinning e caratterizzazione delle fibre rigenerate seta Fibroin

Sintesi di nanocristalli di Upconversion drogato con lantanidi Core-shell per applicazioni cellulari

Segnale Nanosonda rapido aumento di sintesi di nanoparticelle di oro In Situ

In Situ litiati riferimento elettrodo: Elettrodo quattro Design per spettroscopia di impedenza nel operando

Produzione additiva negativa del complesso a forma di carburi di boro

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