We thank&#160;Siheng Wang, Qinxia Wang, Jing Gao, Yingxin Liu for their help with the experiments. This research used resources of the Advanced Photon Source (APS), a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. GeoSoilEnviroCARS (Sector 13) is supported by NSF-Earth Sciences (EAR-1128799), and the Department of Energy, Geosciences (DE-FG02-94ER14466). The development of EHDAC was supported by Externally-heated Diamond Anvil Cell Experimentation (EH-DANCE) project to B. Chen under Education Outreach and Infrastructure Development (EOID) program&#160;from COMPRES under NSF Cooperative Agreement EAR-1606856. X. Lai acknowledges the support from the start-up funding of China University of Geosciences (Wuhan) (no.162301202618). B. Chen acknowledges the support from the U.S. National Science Foundation (NSF) (EAR-1555388 and EAR-1829273).&#160;&#160;J.S. Zhang acknowledges the support from the U.S. NSF (EAR-1664471, EAR-1646527 and EAR-1847707).

1. Ring heater preparation
<ol>
	<li>Fabricating the ring heater base
	<ol>
		<li>Fabricate the ring heater base by a computer numerical control (CNC) milling machine using pyrophyllite based on the designed 3D model. The dimensions of the heater are 22.30 mm in outer diameter (OD), 8.00 mm in inner diameter (ID) and 2.25 mm in thickness. Sinter the heater base in the furnace at 1523 K for &#62;20 hours.</li>
	</ol>
	</li>
	<li>Wiring
	<ol>
		<li>Cut Pt 10 wt% Rh wire (diameter: 0.01 inch) into 3 equal-length wires (about 44 cm each).</li>
		<li>Carefully wind each Pt/Rh wire through the holes in the heater base, leave about 10 cm wire outside of the heater base for connection to the power supply. When wiring, make sure that the wire is lower than the gutters of the base. If it is higher than the gutter, use a proper flat-head screwdriver to press it down.</li>
		<li>Wind more wires on the 10 cm extension wires to reduce the electrical resistance and thus the temperature of the extension wires during heating.</li>
	</ol>
	</li>
	<li>Adding insulators
	<ol>
		<li>Use two small ceramic electrical insulating sleeves to protect the wires extending outside the ring heater base. Mix cement adhesive (e.g., Resbond 919) with water at a ratio of 100:13. Fix those tubes to the ring heater base using the cement mixture. 
		NOTE: The cement needs 4 hours to be cured at 393 K or 24 hours at room temperature.</li>
		<li>Use the high-temp braid sleeving to protect the outside wires.</li>
		<li>Cut two mica rings using a CO2 laser-cutting machine. To electrically insulate the wire, attach one mica ring to each side of the heater by UHU tac.</li>
	</ol>
	</li>
</ol>
2. EHDAC preparation
<ol>
	<li>Gluing diamonds
	<ol>
		<li>Align the diamonds with backing seats using mounting jigs. Use black epoxy to glue the diamond to the backing seat. The black epoxy should be lower than the girdle of the diamond to leave some space for the high-temperature cement.</li>
	</ol>
	</li>
	<li>Alignment
	<ol>
		<li>Glue mica or place the machined pyrophyllite rings under the seats to insulate the seats and DAC thermally. Put the seats with the diamonds into a BX-90 DAC. Align two diamonds under the optical microscope.</li>
	</ol>
	</li>
	<li>Preparing the sample gasket
	<ol>
		<li>Place the rhenium gasket, which is smaller than the hole of the ring heater, between the two diamonds and pre-indent the gasket to approximately 30-45 &#181;m by gently tightening the four screws of DAC. Drill a hole at the center of the indentation by electrical discharge machine (EDM) or laser micro-drilling machine.</li>
	</ol>
	</li>
	<li>Mounting thermocouple
	<ol>
		<li>Fix two small pieces of mica with the cement mixture on the seat of the piston side of DAC to electrically insulate the thermocouples from the seat. Attach two K-type (Chromega-Alomega 0.005&#39;&#39;) or R-type (87%Platium/13%Rhodium&#8211;Platium, 0.005&#8221;) thermocouples to the piston side of the DAC, ensuring that the tips of the thermocouples touch the diamond and close to the culet of the diamond (about 500 &#181;m away). Finally, use the high-temperature cement mixture to fix the thermocouple position and cover the black epoxy on both sides of the DAC.</li>
	</ol>
	</li>
	<li>Heater placement
	<ol>
		<li>Cut the 2300 &#176;F ceramic tape in the shape of the heater base by CO2 laser drilling machine and place it on both sides of DAC (piston and cylinder sides). If it is very easy to move around, use some UHU tac to fix it.</li>
		<li>Place the heater in the piston side of the BX-90 DAC. Use some 2300 &#176;F ceramic tape to fill the gap between the heater and the wall of the DAC.</li>
	</ol>
	</li>
	<li>Gasket placement
	<ol>
		<li>Clean the sample chamber hole of the gasket using a needle or sharpened toothpick to get rid of the metal fragments introduced by the drilling. Use ultrasonic cleaner to clean the gasket for 5-10 min.</li>
		<li>Put two small balls of adhesive putty (e.g., UHU Tac) around the diamond on the piston side of the DAC to support the gasket. Align the sample chamber hole of the gasket to match the center of culet under the optical microscope.</li>
	</ol>
	</li>
</ol>
3. Synthesizing single-crystal ice-VII by EHDAC
<ol>
	<li>Loading sample
	<ol>
		<li>Load one or more ruby spheres and one piece of gold into the sample chamber.</li>
		<li>Load a drop of distilled water in the sample chamber, close the DAC and compress it by tightening the four screws on the DAC to quickly seal the water in the sample chamber.</li>
	</ol>
	</li>
	<li>Pressurizing sample to obtain powder ice-VII
	<ol>
		<li>Determine the pressure of the sample by measuring the fluorescence of ruby spheres using a Raman spectrometer.</li>
		<li>Carefully compress the sample by turning the four screws and monitor the pressure by ruby florescence until it reaches the stability field of ice-VII (&#62;2 GPa). Watch the sample chamber under the optical microscope during compression. Sometimes the coexistence of water fluid and crystallized ice VI is visible if the pressure is close to the phase boundary of water and ice VI.</li>
		<li>Continue compressing the sample chamber until it reaches the pressure in the stability field of ice-VII. In order to melt the ice-VII later, the target pressure is usually between 2 GPa and 10 GPa at 300 K.</li>
	</ol>
	</li>
	<li>Heating sample to obtain single crystal ice-VII
	<ol>
		<li>Put the EHDAC under the optical microscope with a camera connected to the computer. Thermally insulate the DAC from the microscope stage, without blocking the transmitted light path of the microscope.</li>
		<li>Connect the thermocouple to the thermometer and connect the heater to a DC power supply.</li>
		<li>Monitor the melting of ice-VII crystals upon heating to a temperature that is higher than the melting temperature of high-pressure ice-VII determined by the phase diagram of H2O.</li>
		<li>Quench the sample chamber to allow the liquid water to crystallize, and then increase the temperature until some of the smaller ice crystals are molten. Repeat the heating and cooling cycles a few times until only one or a few larger grains remains in the sample chamber.</li>
		<li>Measure the pressure of the sample after the synthesis.</li>
	</ol>
	</li>
</ol>
4. Synchrotron X-ray diffraction and Brillouin spectroscopy collection
<ol>
	<li>Synchrotron X-ray diffraction
	<ol>
		<li>Check if the ice-VII sample synthesized is polycrystalline or a single crystal by synchrotron-based single-crystal XRD15. If it is a single crystal, the diffraction pattern should be diffraction spots instead of powder rings.</li>
		<li>Obtain step scan single-crystal XRD images to determine the orientation and lattice parameters of ice-VII.</li>
		<li>Collect the XRD of pressure marker, i.e. gold, in the sample chamber to determine the pressure.</li>
	</ol>
	</li>
	<li>Brillouin spectroscopy
	<ol>
		<li>Mount the EHDAC on a specialized holder which can be rotated within the vertical plane by changing the &#967; angles. Connect the thermocouples to the temperature controller and connect the heater to the power supply.</li>
		<li>Perform Brillouin spectroscopy measurements every 10-15&#176; &#967; angle at 300 K for a total &#967; angle range of 180&#176; or 270&#176;16. Then heat the sample to high temperatures (e.g., 500 K) and repeat the Brillouin spectroscopy measurement.</li>
	</ol>
	</li>
</ol>

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R., Loubeyre, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temperature+gradients,+wavelength-dependent+emissivity,+and+accuracy+of+high+and+very-high+temperatures+measured+in+the+laser-heated+diamond+cell.">Temperature gradients, wavelength-dependent emissivity, and accuracy of high and very-high temperatures measured in the laser-heated diamond cell.</a> High Pressure Research. 24 (4), 423-445 (2004).</li><li>Goncharov, A. F., Crowhurst, J. 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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phase+transition+in+CaSiO3+perovskite.">Phase transition in CaSiO3 perovskite.</a> Earth and Planetary Science Letters. 260 (3-4), 564-569 (2007).</li><li>Datchi, F., Loubeyre, P., LeToullec, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extended+and+accurate+determination+of+the+melting+curves+of+argon,+helium,+ice+(H+2+O),+and+hydrogen+(H+2).">Extended and accurate determination of the melting curves of argon, helium, ice (H 2 O), and hydrogen (H 2).</a> Physical Review B. 61 (10), 6535 (2000).</li><li>Lai, 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=The+high-pressure+anisotropic+thermoelastic+properties+of+a+potential+inner+core+carbon-bearing+phase,+Fe7C3,+by+single-crystal+X-ray+diffraction.">The high-pressure anisotropic thermoelastic properties of a potential inner core carbon-bearing phase, Fe7C3, by single-crystal X-ray diffraction.</a> American Mineralogist. 103 (10), 1568-1574 (2018).</li><li>Yang, J., Mao, Z., Lin, J. F., Prakapenka, V. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-crystal+elasticity+of+the+deep-mantle+magnesite+at+high+pressure+and+temperature.">Single-crystal elasticity of the deep-mantle magnesite at high pressure and temperature.</a> Earth and Planetary Science Letters. 392, 292-299 (2014).</li><li>Zhang, D., 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=High+pressure+single+crystal+diffraction+at+PX^+2.">High pressure single crystal diffraction at PX^ 2.</a> Journal of Visualized Experiments. (119), e54660 (2017).</li><li>Sinogeikin, S., 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=Brillouin+spectrometer+interfaced+with+synchrotron+radiation+for+simultaneous+X-ray+density+and+acoustic+velocity+measurements.">Brillouin spectrometer interfaced with synchrotron radiation for simultaneous X-ray density and acoustic velocity measurements.</a> Review of Scientific Instruments. 77 (10), 103905 (2006).</li><li>Dubrovinskaia, N., Dubrovinsky, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Whole-cell+heater+for+the+diamond+anvil+cell.">Whole-cell heater for the diamond anvil cell.</a> Review of Scientific Instruments. 74 (7), 3433-3437 (2003).</li><li>Fan, D., 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+simple+external+resistance+heating+diamond+anvil+cell+and+its+application+for+synchrotron+radiation+X-ray+diffraction.">A simple external resistance heating diamond anvil cell and its application for synchrotron radiation X-ray diffraction.</a> Review of Scientific Instruments. 81 (5), 053903 (2010).</li><li>Jenei, Z., Cynn, H., Visbeck, K., Evans, W. 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The authors declare no conflict of interest.

In this work, we described the protocol of preparing the EHDAC for high pressure research. The cell assemblies including a micro-heater and thermal and electrical insulating layers. Previously, there are multiple designs of resistive heaters for different types of DACs or experimental configurations7,17,18,19,20. Most of the heaters are machined by individual ...

The diamond anvil cell (DAC) is one of the most important tools for high pressure research. Coupled with synchrotron-based and conventional analytical methods, it has been widely used to study properties of planetary materials up to multi-megabar pressures and at wide ranges of temperatures. Most planetary interiors are under both high-pressure and high-temperature (HPHT) conditions. It is thus essential to heat the compressed samples in a DAC at high pressures in situ to study the physics and chemistry of planetary interiors. High temperatures are not only required for the investigations of phase and melting relationships and thermodynamic properties of planetary materials, but also help mitigate pressure gradient, promote phase transitions and chemical reactions, and expedite diffusion and recrystallization. Two methods are typically utilized to heat the samples in DACs: laser-heating and internal/external resistive heating methods.
The laser-heated DAC technique has been employed for high-pressure materials science and mineral physics research of planetary interiors1,2. Although increasing number of laboratories have access to the technique, it usually requires significant development and maintenance effort. The laser heating technique has been used to achieve temperatures as high as 7000 K3. However, long-duration stable heating as well as temperature measurement in laser-heating experiments have been a persistent issue. The temperature during laser heating usually fluctuates but can be mitigated by feed-back coupling between thermal emission and laser power. More challenging is controlling and determining the temperature for assembly of multiple phases of different laser absorbance. The temperature also has a considerably large gradient and uncertainties (hundreds of K), although recent technical development effort has been used to mitigate this issue4,5,6. Temperature gradients in the heated sample area sometimes may further introduce chemical heterogeneities caused by diffusion, re-partitioning or partial melting. In addition, temperatures less than 1100 K typically could not be measured precisely without customized detectors with high sensitivity in the infrared wavelength range.
The EHDAC uses resistive wires or foils around the gasket/seat to heat the entire sample chamber, which provides the ability of heating the sample to ~900 K without a protective atmosphere (such as Ar/H2 gas) and to ~1300 K with a protective atmosphere7. The oxidation and graphitization of diamonds at higher temperatures limit the highest achievable temperatures using this method. Although the temperature range is limited compared with laser-heating, it provides more stable heating for a long duration and a smaller temperature gradient8, and is well suited to be coupled with various detection and diagnostic methods, including optical microscope, X-ray diffraction (XRD), Raman spectroscopy, Brillouin spectroscopy and Fourier-transform infrared spectroscopy9. Therefore, the EHDAC has become a useful tool to study various material properties at HPHT conditions, such as phase stability and transitions10,11, melting curves12, thermal equation of state13, and elasticity14.
The BX-90 type DAC is a newly developed piston-cylinder type DAC with large aperture (90&#176; at maximum) for XRD and laser spectroscopy measurements9, with the space and openings to mount a miniature resistive heater. The U-shaped cut on the cylinder side also provides room to release the stress between the piston and the cylinder side caused by temperature gradient. Therefore, it has recently been widely used in powder or single-crystal XRD and Brillouin measurements with the external-heating setup. In this study, we describe a reproducible and standardized protocol for preparing EHDACs and demonstrated single-crystal XRD as well as Brillouin spectroscopy measurements of synthesized single-crystal ice-VII using the EHDAC at 11.2 GPa and 300-500 K.

<table>
	<tbody>
		<tr>
			<td>Au</td>
			<td>N/A</td>
			<td>N/A</td>
			<td>for pressure calibration</td>
		</tr>
		<tr>
			<td>Deionized water</td>
			<td>Fisher Scientific</td>
			<td>7732-18-5</td>
			<td>for the starting material of ice-VII synthesis</td>
		</tr>
		<tr>
			<td>Diamond anvil cell</td>
			<td>SciStar, Beijing</td>
			<td>N/A</td>
			<td>for generating high pressure</td>
		</tr>
		<tr>
			<td>K-type thermocouple</td>
			<td>Omega</td>
			<td>L-0044K</td>
			<td>for measuring high temperature</td>
		</tr>
		<tr>
			<td>Mica</td>
			<td>Spruce Pine Mica Company</td>
			<td>N/A</td>
			<td>for electrical insulation</td>
		</tr>
		<tr>
			<td>Pt 10wt%Rh</td>
			<td>Alfa Aesar</td>
			<td>10065</td>
			<td>for heater</td>
		</tr>
		<tr>
			<td>Pyrophyllite</td>
			<td>McMaster-Carr</td>
			<td>8479K12</td>
			<td>for fabricating the heater base</td>
		</tr>
		<tr>
			<td>Re</td>
			<td>Sigma-Aldrich</td>
			<td>267317</td>
			<td>for the gasket of diamond anvil cell</td>
		</tr>
		<tr>
			<td>Resbond 919 Ceramic Adhesive</td>
			<td>Cotronics Corp</td>
			<td>Resbond 919-1</td>
			<td>for insulating heating wires and mounting diamonds on seats</td>
		</tr>
		<tr>
			<td>Ruby</td>
			<td>N/A</td>
			<td>N/A</td>
			<td>for pressure calibration</td>
		</tr>
		<tr>
			<td>Ultra-Temp 2300F ceramic tape</td>
			<td>McMaster Carr Supply</td>
			<td>390-23M</td>
			<td>for thermal insulation</td>
		</tr>
	</tbody>
</table>

an externally-heated diamond anvil cell for synthesis and single-crystal elasticity determination of ice-vii at high pressure-temperature conditions

The externally-heated diamond anvil cell (EHDAC) can be used to generate simultaneously high-pressure and high-temperature conditions found in Earth&#8217;s and planetary interiors. Here we describe the design and fabrication of the EHDAC assemblies and accessories, including ring resistive heaters, thermal and electrical insulating layers, thermocouple placement, as well as the experimental protocol for preparing the EHDAC using these parts. The EHDAC can be routinely used to generate megabar pressures and up to 900 K temperatures in open air, and potentially higher temperatures up to ~1200 K with a protective atmosphere (i.e., Ar mixed with 1% H2). Compared with a laser-heating method for reaching temperatures typically &#62;1100 K, external heating can be easily implemented and provide a more stable temperature at &#8804;900 K and less temperature gradients to the sample. We showcased the application of the EHDAC for synthesis of single crystal ice-VII and studied its single-crystal elastic properties using synchrotron-based X-ray diffraction and Brillouin scattering at simultaneously high-pressure high-temperature conditions.

In this report, we used the fabricated resistive micro-heater and BX-90 DAC for the EHDAC experiment (Figure 1 and Figure 2). Figure 1 shows the machining and fabrication processes of the ring heaters. The standard dimensions of the heater base are 22.30 mm in outer diameter, 8.00&#160;mm in inner diameter and 2.25 mm in thickness. The dimensions of the ring heater can be adjusted to accommodate various types of seats and diamonds.<...

Watch this Scientific Journal Video about An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions at JoVE.c

An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions

This work focuses on the standard protocol for preparing the externally-heated diamond anvil cell (EHDAC) for generating high-pressure and high-temperature (HPHT) conditions. The EHDAC is employed to investigate materials in Earth and planetary interiors under extreme conditions, which can be also used in solid state physics and chemistry studies.

The externally-heated diamond anvil cell (EHDAC) can be used to generate simultaneously high-pressure and high-temperature conditions found in ...

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5.8K Views.  China University of Geosciences (Wuhan). This work focuses on the standard protocol for preparing the externally-heated diamond anvil cell (EHDAC) for generating high-pressure and high-temperature (HPHT) conditions. The EHDAC is employed to investigate materials in Earth and planetary interiors under extreme conditions, which can be also used in solid state physics and chemistry studies.

Video: An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions

Rapid High Throughput Amylose Determination in Freeze Dried Potato Tuber Samples

This protocol describes a high through put colorimetric method that relies on the formation of a complex between iodine and chains of glucose molecules in starch. Iodine forms complexes with both amylose and long chains within amylopectin. After the addition of iodine to a starch sample, the maximum absorption of amylose and amylopectin occurs at 620 and 550 nm, respectively. The amylose/amylopectin ratio can be estimated from the ratio of the 620 and 550 nm absorbance values and comparing them to a standard curve in which specific known concentrations are plotted against absorption values. This high throughput, inexpensive method is reliable and reproducible, allowing the evaluation of large populations of potato clones.&#160;

This protocol describes a high through put colorimetric method that relies on the formation of a complex between iodine and chains of glucose molecules in ...

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes

The procedures described in this article involve the synthesis and isolation of hypervalent iodonium alkynyl triflates (HIATs) and their subsequent reactions with azides to form cyanocarbene intermediates. The synthesis of hypervalent iodonium alkynyl triflates can be facile, but difficulties stem from their isolation and reactivity. In particular, the necessity to use filtration under inert atmosphere at -45 &deg;C for some HIATs requires special care and equipment. Once isolated, the compounds can be stored and used in reactions with azides to form cyanocarbene intermediates. 
The evidence for cyanocarbene generation is shown by visible extrusion of dinitrogen as well as the characterization of products that occur from O-H insertion, sulfoxide complexation, and cyclopropanation. A side reaction of the cyanocarbene formation is the generation of a vinylidene-carbene and the conditions to control this process are discussed. There is also potential to form a hypervalent iodonium alkenyl triflate and the means of isolation and control of its generation are provided. The O-H insertion reaction involves using a HIAT, sodium azide or tetrabutylammonium azide, and methanol as solvent/substrate. The sulfoxide complexation reaction uses a HIAT, sodium azide or tetrabutylammonium azide, and dimethyl sulfoxide as solvent. The cyclopropanations can be performed with or without the use of solvent. The azide source must be tetrabutylammonium azide and the substrate shown is styrene.

Herein is described the synthesis, isolation, and reactions of hypervalent iodonium alkynyl triflates (HIATs) with azides to generate cyanocarbenes. The procedures will involve air-sensitive and cryogen techniques, including cold filtration under an inert atmosphere. Handling and safety of the synthesized compounds will also be discussed.

The procedures described in this article involve the synthesis and isolation of hypervalent iodonium alkynyl triflates (HIATs) and their subsequent ...

Synthesis of Immunotargeted Magneto-plasmonic Nanoclusters

Magnetic and plasmonic properties combined in a single nanoparticle provide a synergy that is advantageous in a number of biomedical applications including contrast enhancement in novel magnetomotive imaging modalities, simultaneous capture&#160;and detection of circulating tumor cells (CTCs),&#160;and multimodal molecular imaging combined with photothermal therapy of cancer cells. These applications have stimulated significant interest in development of protocols for synthesis of magneto-plasmonic nanoparticles with optical absorbance in the near-infrared (NIR) region and a strong magnetic moment. Here, we present a novel protocol for synthesis of such hybrid nanoparticles that is based on an oil-in-water microemulsion method. The unique feature of the protocol described herein is synthesis of magneto-plasmonic nanoparticles of various sizes from primary blocks which also have magneto-plasmonic characteristics. This approach yields nanoparticles with a high density of magnetic and plasmonic functionalities which are uniformly distributed throughout the nanoparticle volume. The hybrid nanoparticles can be easily functionalized by attaching antibodies through the Fc moiety leaving the Fab portion that is responsible for antigen binding available for targeting.

Here, we describe a protocol for synthesis of magneto-plasmonic nanoparticles with a strong magnetic moment and a strong near-infrared (NIR) absorbance. The protocol also includes antibody conjugation to the nanoparticles through the Fc moiety for various biomedical applications which require molecular specific targeting.

Magnetic and plasmonic properties combined in a single nanoparticle provide a synergy that is advantageous in a number of biomedical applications ...

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large extinction coefficients which can be tuned across the visible spectrum. Research into the plasmonic enhancement of optical transitions has become popular, due to the possibility of altering and in some cases improving photo-absorption or emission properties of nearby chromophores such as molecular dyes or quantum dots. The electric field of the plasmon can couple with the excitation dipole of a chromophore, perturbing the electronic states involved in the transition and leading to increased absorption and emission rates. These enhancements can also be negated at close distances by energy transfer mechanism, making the spatial arrangement of the two species critical. Ultimately, enhancement of light harvesting efficiency in plasmonic solar cells could lead to thinner and, therefore, lower cost devices. The development of hybrid core/shell particles could offer a solution to this issue. The addition of a dielectric spacer between a gold nanoparticles and a chromophore is the proposed method to control the exciton plasmon coupling strength and thereby balance losses with the plasmonic gains. A detailed procedure for the coating of gold nanoparticles with CdS and ZnS semiconductor shells is presented. The nanoparticles show high uniformity with size control in both the core gold particles and shell species allowing for a more accurate investigation into the plasmonic enhancement of external chromophores.

The synthesis of uniform gold nanoparticles coated with semiconductor shells of CdS or ZnS is performed. The semiconductor coating is conducted by first depositing a silver sulfide shell and exchanging the silver cations for zinc or cadmium cations.

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large ...

A Simple Method for the Size Controlled Synthesis of Stable Oligomeric Clusters of Gold Nanoparticles under Ambient Conditions

Reducing dilute aqueous HAuCl4 with sodium thiocyanate (NaSCN) under alkaline conditions produces 2 to 3 nm diameter nanoparticles. Stable grape-like oligomeric clusters of these yellow nanoparticles of narrow size distribution are synthesized under ambient conditions via two methods. The delay-time method controls the number of subunits in the oligoclusters by varying the time between the addition of HAuCl4 to alkaline solution and the subsequent addition of reducing agent, NaSCN. The yellow oligoclusters produced range in size from ~3 to ~25 nm. This size range can be further extended by an add-on method utilizing hydroxylated gold chloride (Na+[Au(OH4-x)Clx]-) to auto-catalytically increase the number of subunits in the as-synthesized oligocluster nanoparticles, providing a total range of 3 nm to 70 nm. The crude oligocluster preparations display narrow size distributions and do not require further fractionation for most purposes. The oligoclusters formed can be concentrated &#62;300 fold without aggregation and the crude reaction mixtures remain stable for weeks without further processing. Because these oligomeric clusters can be concentrated before derivatization they allow expensive derivatizing agents to be used economically. In addition, we present two models by which predictions of particle size can be made with great accuracy.

We describe a simple method for producing highly stable oligomeric clusters of gold nanoparticles via the reduction of chloroauric acid (HAuCl4) with sodium thiocyanate (NaSCN). The oligoclusters have a narrow size distribution and can be produced with a wide range of sizes and surface coats.

Reducing dilute aqueous HAuCl4 with sodium thiocyanate (NaSCN) under alkaline conditions produces 2 to 3 nm diameter nanoparticles. Stable grape-like ...

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

Molecules bearing trifluoromethoxy (OCF3) group often show desired pharmacological and biological properties. However, facile synthesis of trifluoromethoxylated aromatic compounds remains a formidable challenge in organic synthesis. Conventional approaches often suffer from poor substrate scope, or require use of highly toxic, difficult-to-handle, and/or thermally labile reagents. Herein, we report a user-friendly protocol for the synthesis of methyl 4-acetamido-3-(trifluoromethoxy)benzoate using 1-trifluoromethyl-1,2-benziodoxol-3(1H)-one (Togni reagent II). Treating methyl 4-(N-hydroxyacetamido)benzoate (1a) with Togni reagent II in the presence of a catalytic amount of cesium carbonate (Cs2CO3) in chloroform at RT afforded methyl 4-(N-(trifluoromethoxy)acetamido)benzoate (2a). This intermediate was then converted to the final product methyl 4-acetamido-3-(trifluoromethoxy)benzoate (3a) in nitromethane at 120 &#176;C. This procedure is general and can be applied to the synthesis of a broad spectrum of ortho-trifluoromethoxylated aniline derivatives, which could serve as useful synthetic building blocks for the discovery and development of new pharmaceuticals, agrochemicals, and functional materials.

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

An operationally simple procedure for the synthesis of ortho-trifluoromethoxylated aniline derivatives via a two-step sequence of O-trifluoromethylation of N-aryl-N-hydroxyacetamide followed by thermally induced intramolecular OCF3-migration is reported.

Molecules bearing trifluoromethoxy (OCF3) group often show desired pharmacological and biological properties. However, facile synthesis of ...

Synthesis of a Water-soluble Metal&#8211;Organic Complex Array

We demonstrate a method for the synthesis of a water-soluble multimetallic peptidic array containing a predetermined sequence of metal centers such as Ru(II), Pt(II), and Rh(III). The compound, named as a water-soluble metal-organic complex array (WSMOCA), is obtained through 1) the conventional solution-chemistry-based preparation of the corresponding metal complex monomers having a 9-fluorenylmethyloxycarbonyl (Fmoc)-protected amino acid moiety and 2) their sequential coupling together with other water-soluble organic building units on the surface-functionalized polymeric resin by following the procedures originally developed for the solid-phase synthesis of polypeptides, with proper modifications. Traces of reactions determined by mass spectrometric analysis at the representative coupling steps in stage 2 confirm the selective construction of a predetermined sequence of metal centers along with the peptide backbone. The WSMOCA cleaved from the resin at the end of stage 2 has a certain level of solubility in aqueous media dependent on the pH value and/or salt content, which is useful for the purification of the compound.

Synthesis of a Water-soluble Metal&amp;#8211;Organic Complex Array

A potential general method for the synthesis of water-soluble multimetallic peptidic arrays containing a predetermined sequence of metal centers is presented.

We demonstrate a method for the synthesis of a water-soluble multimetallic peptidic array containing a predetermined sequence of metal centers such as ...

High Pressure Single Crystal Diffraction at PX^2

In this report we describe detailed procedures for carrying out single crystal X-ray diffraction experiments with a diamond anvil cell (DAC) at the GSECARS 13-BM-C beamline at the Advanced Photon Source. The DAC program at 13-BM-C is part of the Partnership for Extreme Xtallography (PX^2) project. BX-90 type DACs with conical-type diamond anvils and backing plates are recommended for these experiments. The sample chamber should be loaded with noble gas to maintain a hydrostatic pressure environment. The sample is aligned to the rotation center of the diffraction goniometer. The MARCCD area detector is calibrated with a powder diffraction pattern from LaB6. The sample diffraction peaks are analyzed with the ATREX software program, and are then indexed with the RSV software program. RSV is used to refine the UB matrix of the single crystal, and with this information and the peak prediction function, more diffraction peaks can be located. Representative single crystal diffraction data from an omphacite (Ca0.51Na0.48)(Mg0.44Al0.44Fe2+0.14Fe3+0.02)Si2O6 sample were collected. Analysis of the data gave a monoclinic lattice with P2/n space group at 0.35 GPa, and the lattice parameters were found to be: a = 9.496 &#177;0.006 &#197;, b = 8.761 &#177;0.004 &#197;, c = 5.248 &#177;0.001 &#197;, &#946; = 105.06 &#177;0.03&#186;, &#945; = &#947; = 90&#186;.

In this report, we describe detailed procedures for carrying out single crystal X-ray diffraction experiments with a diamond anvil cell at the GSECARS 13-BM-C beamline at the Advanced Photon Source. ATREX and RSV programs are used to analyze the data.

In this report we describe detailed procedures for carrying out single crystal X-ray diffraction experiments with a diamond anvil cell (DAC) at the ...

Synthesis of High Purity Nonsymmetric Dialkylphosphinic Acid Extractants

We present the synthesis of (2,3-dimethylbutyl)(2,4,4&#39;-trimethylpentyl)phosphinic acid as an example to demonstrate a method for the synthesis of high purity nonsymmetric dialkylphosphinic acid extractants. Low toxic sodium hypophosphite was chosen as the phosphorus source to react with olefin A (2,3-dimethyl-1-butene) to generate a monoalkylphosphinic acid intermediate. Amantadine was adopted to remove the dialkylphosphinic acid byproduct, as only the monoalkylphosphinic acid can react with amantadine to form an amantadine&#8729;mono-alkylphosphinic acid salt, while the dialkylphosphinic acid cannot react with amantadine due to its large steric hindrance. The purified monoalkylphosphinic acid was then reacted with olefin B (diisobutylene) to yield nonsymmetric dialkylphosphinic acid (NSDAPA). The unreacted monoalkylphosphinic acid can be easily removed by a simple base-acid post-treatment and other organic impurities can be separated out through the precipitation of the cobalt salt. The structure of the (2,3-dimethylbutyl)(2,4,4&#39;-trimethylpentyl)phosphinic acid was confirmed by 31P NMR, 1H NMR, ESI-MS, and FT-IR. The purity was determined by a potentiometric titration method, and the results indicate that the purity can exceed 96%.

A protocol for the synthesis of high purity nonsymmetric dialkylphosphinic acid extractants is presented, taking (2,3-dimethylbutyl)(2,4,4&#39;-trimethylpentyl)phosphinic acid as an example.

We present the synthesis of (2,3-dimethylbutyl)(2,4,4&#39;-trimethylpentyl)phosphinic acid as an example to demonstrate a method for the synthesis of high ...

Synthesis of Substrate-Bound Au Nanowires Via an Active Surface Growth Mechanism

Advancing synthetic capabilities is important for the development of nanoscience and nanotechnology. The synthesis of nanowires has always been a challenge, as it requires asymmetric growth of symmetric crystals. Here, we report a distinctive synthesis of substrate-bound Au nanowires. This template-free synthesis employs thiolated ligands and substrate adsorption to achieve the continuous asymmetric deposition of Au in solution at ambient conditions. The thiolated ligand prevented the Au deposition on the exposed surface of the seeds, so the Au deposition only occurs at the interface between the Au seeds and the substrate. The side of the newly deposited Au nanowires is immediately covered with the thiolated ligand, while the bottom facing the substrate remains ligand-free and active for the next round of Au deposition. We further demonstrate that this Au nanowire growth can be induced on various substrates, and different thiolated ligands can be used to regulate the surface chemistry of the nanowires. The diameter of the nanowires can also be controlled with mixed ligands, in which another &#34;bad&#34; ligand could turn on the lateral growth. With the understanding of the mechanism, Au nanowire-based nanostructures can be designed and synthesized.

We report a solution-based method to synthesize substrate-bound Au nanowires. By tuning the molecular ligands used during the synthesis, the Au nanowires can be grown from various substrates with different surface properties. Au nanowire-based nanostructures can also be synthesized by adjusting the reaction parameters.