This work was supported in part by grants-in-aid KAKENHI from the Japan Society for the Promotion of Science (JSPS) and the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) Japan (#26104539, #26620020, #26810011, #15H03766, #15KT0060, #16H00826, and #16K13927); the Konica Minolta Science and Technology Foundation; the "Planting Seeds for Research" program of TokyoTech; the Imaging Science Project of the Center for Novel Science Initiatives (CNSI) at the National Institutes of Natural Sciences (NINS) (#IS261006); the RIKEN-IMS joint program on "Extreme Photonics;" and the Consortium for Photon Science and Technology (CPhoST).

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The authors have nothing to disclose.

Il presente procedimento permette di acquisire un filmato in tempo reale della rotazione molecolare con una configurazione di immagini 2D fessura base. Poiché gli ioni osservate passano attraverso la fessura, passo 1.5 è una delle fasi critiche. I bordi delle lame a fessura devono essere taglienti. Quando c&#39;è un piccolo difetto, come un dente 0,3 mm fessura, un graffio si osserva l&#39;immagine ioni nella (Figura 6). In tal caso, la lama a fessura deve essere lucidato con 2.000-grana carta vetrat...

Per una comprensione e una migliore utilizzazione della natura dinamica delle molecole, è essenziale visualizzare chiaramente movimenti molecolari di interesse. L&#39;imaging esplosione Coulomb tempo risolto è uno dei potenti approcci per raggiungere questo obiettivo 1, 2, 3. In questo approccio, le dinamiche molecolari di interesse vengono avviate da un campo laser di pompa ultracorti e vengono sondati da un impulso probe ritardata. Su sonda irraggiamento, molecole ionizzate moltiplicano e suddivisi in frammenti ionici causa della repulsione coulombiana. La distribuzione spaziale degli ioni espulsi è una misura della struttura molecolare e l&#39;orientamento spaziale a irradiazione sonda. Una sequenza di misurazione scansione del tempo di ritardo pump-probe porta alla creazione di un film molecolare. È interessante notare che, per il caso più semplice - molecole biatomiche - distribuzione angolare degli ioni espulsiriflette direttamente la distribuzione dell&#39;asse molecolare (cioè, la funzione d&#39;onda rotazionale quadrato). Per quanto riguarda il processo di pompa, recenti progressi nel controllo coerente del moto molecolare utilizzando campi laser ultracorti ha portato alla creazione di pacchetti d&#39;onda rotazione altamente controllate 4, 5. Inoltre, la direzione di rotazione può essere controllato attivamente utilizzando un campo di polarizzazione controllato laser 6, 7, 8. È stato quindi previsto che un quadro dettagliato di rotazione molecolare, compreso nature onda, potrebbe essere visualizzato quando la tecnica di imaging esplosione coulombiana è combinata con un tale processo pompa 9, 10, 11, 12, 13. Tuttavia, abbiamo alcunivolte incontrano difficoltà sperimentali associati ai metodi di imaging esistenti, come indicato di seguito. Lo scopo di questo lavoro è quello di presentare un nuovo modo di superare queste difficoltà e di creazione di un filmato di alta qualità di pacchetti d&#39;onda di rotazione molecolare. Il primo film sperimentale di rotazione molecolare presa con il presente metodo, insieme con le sue implicazioni fisiche, sono stati presentati nella precedente carta 11. Lo sfondo dello sviluppo, l&#39;aspetto teorico dettagliata della attuale tecnica di imaging, e il confronto con altre tecniche esistenti saranno date in un prossimo documento. Qui, ci si concentrerà principalmente sugli aspetti pratici e tecnici della procedura, compresa la combinazione della configurazione ottica tipica pump-probe e il nuovo apparato di immagini. Come nel precedente lavoro, il sistema di destinazione è unidirezionale rotazione molecole di azoto 11. La principale difficoltà sperimentale dellaconfigurazione di imaging, schematicamente illustrato in figura 1 esistente, ha a che fare con la posizione del rilevatore, o l&#39;angolo della telecamera. Poiché l&#39;asse di rotazione coincide con la propagazione laser all&#39;asse 6, 7, 8 in rotazione molecolare laser-indotta dal campo, non è pratico installare un rilevatore lungo l&#39;asse di rotazione. Quando il rivelatore è installato in modo da evitare l&#39;irradiazione laser, l&#39;angolo della telecamera corrisponde a un&#39;osservazione lato di rotazione. In questo caso, non è possibile ricostruire l&#39;orientamento originale molecole dall&#39;immagine proiettata (2D) ione 14. Un imaging 3D rilevatore 14, 15, 16, 17, 18, 19, con la quale il tempo di arrivo al rivelatore superiore e IMPAC ioneposizioni t possono essere misurati, ha offerto un modo unico per osservare direttamente la rotazione molecolare utilizzando Coulomb esplosione di imaging 10, 12. Tuttavia, i conteggi di ioni accettabili per colpo laser sono basse (tipicamente &lt;10 ioni) nel rivelatore 3D, che significa che è difficile creare un film lungo di moto molecolare con alta qualità di immagine 14. Il tempo morto dei rivelatori (tipicamente NS) colpisce anche la risoluzione dell&#39;immagine e l&#39;efficienza di imaging. Inoltre non è un compito semplice per fare un buon pump-probe sovrapposizione fascio di ioni attraverso il monitoraggio immagine in tempo reale con una frequenza di ripetizione del laser di &lt;~ 1 kHz. Anche se diversi gruppi hanno osservato pacchetti d&#39;onda di rotazione con la tecnica 3D, le informazioni spaziali è stato limitato e / o diretta, e una visualizzazione dettagliata di onda della natura, comprese le strutture nodali complicate, non è stato raggiunto il 10, 12. L&#39;essenzala nuova tecnica di imaging è l&#39;uso della &quot;nuova angolazione&quot; in Figura 1. In questa configurazione, l&#39;esposizione del fascio laser per un rivelatore è evitata mentre il rilevatore 2D è parallelo al piano di rotazione, portando all&#39;osservazione dalla direzione dell&#39;asse di rotazione. La fessura consente solo lo ione nel piano di rotazione (il piano di polarizzazione degli impulsi laser) per contribuire a un&#39;immagine. Un rivelatore 2D, che offre una velocità di conteggio più alto (tipicamente ~ 100 ioni) di un rivelatore 3D, può essere utilizzato. La configurazione dell&#39;elettronica è più semplice rispetto al caso di rilevamento 3D, mentre l&#39;efficienza di misurazione è maggiore. In termini di tempo di ricostruzione matematica, come Abel inversione 14, inoltre, non è necessario per estrarre le informazioni angolare. Queste caratteristiche portano alla semplice ottimizzazione del sistema di misura e alla produzione di film di alta qualità. Un apparato di immagini di particelle cariche serie 2D / 3D può essere facilmente modificato per la presente witho configurazioneut l&#39;uso di apparecchiature costose.

<table border="0" cellpadding="0" cellspacing="0" width="618">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:249px;">CMOS camera</td>
			<td style="width:83px;">Toshiba TELI</td>
			<td style="width:119px;">BU-238M-ES</td>
			<td style="width:167px;">equipped with SONY IMX174 sensor</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">High voltage switch</td>
			<td style="width:83px;">Behlke</td>
			<td style="width:119px;">HTS-41-03-GSM</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">High voltage switch</td>
			<td style="width:83px;">Behlke</td>
			<td style="width:119px;">HTS-80-03</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:249px;">Digital delay generator</td>
			<td style="width:83px;">Stanford research systems</td>
			<td style="width:119px;">DG535</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:249px;">Digital delay generator</td>
			<td style="width:83px;">Stanford research systems</td>
			<td style="width:119px;">DG645</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">Microchannel plate</td>
			<td style="width:83px;">Photonis</td>
			<td align="right" style="width:119px;">3075</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:249px;">Pulsed valve</td>
			<td style="width:83px;">LAMID LTD</td>
			<td style="width:119px;">Even-Lavie valve&#160;</td>
			<td style="width:167px;">High repetition, room temperature model</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:249px;">Molecular beam skimmers</td>
			<td style="width:83px;">Institute for Molecular Science</td>
			<td style="width:119px;">13C11</td>
			<td style="width:167px;">3 and 1.5 mm center hole, 25 degrees full inner angle, and ~50 mm length</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">Optical Comparator</td>
			<td style="width:83px;">Nikon</td>
			<td style="width:119px;">V-24B</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:249px;">DPSS laser</td>
			<td style="width:83px;">Lighthouse Photonics</td>
			<td style="width:119px;">Sprout</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">Femtosecond Ti:Sapphire oscillator</td>
			<td style="width:83px;">KMLabs</td>
			<td style="width:119px;">Halcyon</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">Femtosecond Ti:Sapphire amplifier</td>
			<td style="width:83px;">Quantronix</td>
			<td style="width:119px;">Odin-II HE</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">Motorized linear stage</td>
			<td style="width:83px;">Sigma Koki</td>
			<td style="width:119px;">KST(GS)-100X</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">Manual X-stage</td>
			<td style="width:83px;">Sigma Koki</td>
			<td style="width:119px;">TSD-601S</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:249px;">High resolution mirror mount</td>
			<td style="width:83px;">Newport</td>
			<td style="width:119px;">Suprema SX100-F2KN-254</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:249px;">High resolution mirror mount</td>
			<td style="width:83px;">LIOP-TEC GmbH</td>
			<td style="width:119px;">SR100-100R-2-HS</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:249px;">Polarization checker</td>
			<td style="width:83px;">Paradigm Devices, Inc.</td>
			<td style="width:119px;">O-tool VIS</td>
			<td></td>
		</tr>
		<tr height="44">
			<td height="44" style="height:44px;width:249px;">Instrument communication interface</td>
			<td style="width:83px;">National Instruments</td>
			<td style="width:119px;">NI-MAX</td>
			<td></td>
		</tr>
		<tr height="45">
			<td height="45" style="height:45px;width:249px;">Graphical development environment for measurement programs</td>
			<td style="width:83px;">National Instruments</td>
			<td style="width:119px;">LabVIEW 2014</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:249px;">Laser line dielectric mirror</td>
			<td style="width:83px;">CVI/LEO</td>
			<td style="width:119px;">TLM2-400/800-45UNP</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">Laser line dielectric mirror</td>
			<td style="width:83px;">Altechna</td>
			<td colspan="2">Low GDD Ultrafast mirror</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:249px;">Laser line dielectric mirror</td>
			<td style="width:83px;">Altechna</td>
			<td colspan="2">Low GDD Ultrafast mirror</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:249px;">Femtosecond polarizer</td>
			<td style="width:83px;">Advanced Thin Films</td>
			<td style="width:119px;">PBS-GVD</td>
			<td></td>
		</tr>
	</tbody>
</table>

direct imaging of laser-driven ultrafast molecular rotation

Vi presentiamo un metodo per la visualizzazione ultraveloci molecolari dinamiche pacchetto onda rotazione laser-indotta,. Abbiamo sviluppato una nuova impostazione di imaging esplosione 2-dimensionale Coulomb, in cui si realizza un angolo di ripresa fino a quel momento, impraticabile. Nella nostra tecnica di imaging, molecole biatomiche sono irradiati con un forte impulso laser polarizzata circolarmente. Gli ioni atomici espulsi vengono accelerati perpendicolarmente alla propagazione laser. Gli ioni giacenti nel piano di polarizzazione laser vengono selezionati attraverso l&#39;uso di una fenditura meccanica e ripreso con un alto rendimento, rivelatore 2-dimensional installato parallelo al piano di polarizzazione. Poiché un circolarmente polarizzata (isotropo) Coulomb impulso esplodere viene utilizzato, la distribuzione angolare osservata degli ioni espulsi corrisponde direttamente alla funzione d&#39;onda quadrata rotazione al momento della irradiazione impulsi. Per creare un filmato in tempo reale della rotazione molecolare, la presente tecnica di imaging è combinato con una pompa-probe a femtosecondi oconfigurazione ptical in cui gli impulsi di pompa create unidirezionalmente rotazione formazioni molecolari. A causa della elevata produttività immagine del nostro sistema di rilevamento, la condizione sperimentale pompa-sonda può essere facilmente ottimizzato controllando un&#39;istantanea in tempo reale. Come risultato, la qualità del filmato osservata è sufficientemente elevata per visualizzare la natura ondulatoria dettagliata del moto. Si segnala altresì che l&#39;attuale tecnica può essere implementato in configurazioni esistenti imaging standard ionici, offrendo una nuova angolazione o punto di vista dei sistemi molecolari senza necessità di modifica estesa.

La figura 4A mostra una sonda di sola immagine raw della N 2+ ioni espulso su sonda irradiazione (esplosione Coulomb), preso per il colpo del laser una sonda. Ogni punto luminoso corrisponde ad uno ione. La figura 4B mostra un&#39;immagine riassunto di 10.000 immagini Camera RAW binarizzate. Queste immagini dimostrano che la nostra configurazione di imaging può monitorare le molecole di tutti gli angoli di orientamento del piano di pol...

Watch this Scientific Journal Video about Direct Imaging of Laser-driven Ultrafast Molecular Rotation at JoVE.com

Direct Imaging of Laser-driven Ultrafast Molecular Rotation

We present a protocol for creating a real-time movie of a molecular rotational wave packet using a high-resolution Coulomb explosion imaging setup.

Direct Imaging di laser-driven ultraveloce rotazione molecolare

We present a method for visualizing laser-induced, ultrafast molecular rotational wave packet dynamics. We have developed a new 2-dimensional Coulomb ...

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Chemistry

Chemical Bonding: Molecular Geometry and Bonding Theories

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9.6K Views.  Tokyo Institute of Technology. We present a protocol for creating a real-time movie of a molecular rotational wave packet using a high-resolution Coulomb explosion imaging setup.

Video: Direct Imaging of Laser-driven Ultrafast Molecular Rotation

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.

Sintesi di Immunotargeted magneto-plasmonica nanocluster

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

Ricerca

Chimica

Measurements of Long-range Electronic Correlations During Femtosecond Diffraction Experiments Performed on Nanocrystals of Buckminsterfullerene

The precise details of the interaction of intense X-ray pulses with matter are a topic of intense interest to researchers attempting to interpret the results of femtosecond X-ray free electron laser (XFEL) experiments. An increasing number of experimental observations have shown that although nuclear motion can be negligible, given a short enough incident pulse duration, electronic motion cannot be ignored. The current and widely accepted models assume that although electrons undergo dynamics driven by interaction with the pulse, their motion could largely be considered &#39;random&#39;. This would then allow the supposedly incoherent contribution from the electronic motion to be treated as a continuous background signal and thus ignored. The original aim of our experiment was to precisely measure the change in intensity of individual Bragg peaks, due to X-ray induced electronic damage in a model system, crystalline C60. Contrary to this expectation, we observed that at the highest X-ray intensities, the electron dynamics in C60 were in fact highly correlated, and over sufficiently long distances that the positions of the Bragg reflections are significantly altered. This paper describes in detail the methods and protocols used for these experiments, which were conducted both at the Linac Coherent Light Source (LCLS) and the Australian Synchrotron (AS) as well as the crystallographic approaches used to analyse the data.

We describe an experiment designed to probe the electronic damage induced in nanocrystals of Buckminsterfullerene (C60) by intense, femtosecond pulses of X-rays. The experiment found that, surprisingly, rather than being stochastic, the X-ray induced electron dynamics in C60 are highly correlated, extending over hundreds of unit cells within the crystals1.

Misurazioni delle correlazioni a lungo raggio elettroniche durante gli esperimenti di diffrazione a femtosecondi eseguiti su nanocristalli di Buckminsterfullerene

The precise details of the interaction of intense X-ray pulses with matter are a topic of intense interest to researchers attempting to interpret the ...

Microfluidic Chips for In Situ Crystal X-ray Diffraction and In Situ Dynamic Light Scattering for Serial Crystallography

This protocol describes fabricating microfluidic devices with low X-ray background optimized for goniometer based fixed target serial crystallography. The devices are patterned from epoxy glue using soft lithography and are suitable for in situ X-ray diffraction experiments at room temperature. The sample wells are lidded on both sides with polymeric polyimide foil windows that allow diffraction data collection with low X-ray background. This fabrication method is undemanding and inexpensive. After the sourcing of a SU-8 master wafer, all fabrication can be completed outside of a cleanroom in a typical research lab environment. The chip design and fabrication protocol utilize capillary valving to microfluidically split an aqueous reaction into defined nanoliter sized droplets. This loading mechanism avoids the sample loss from channel dead-volume and can easily be performed manually without using pumps or other equipment for fluid actuation. We describe how isolated nanoliter sized drops of protein solution can be monitored in situ by dynamic light scattering to control protein crystal nucleation and growth. After suitable crystals are grown, complete X-ray diffraction datasets can be collected using goniometer based in situ fixed target serial X-ray crystallography at room temperature. The protocol provides custom scripts to process diffraction datasets using a suite of software tools to solve and refine the protein crystal structure. This approach avoids the artefacts possibly induced during cryo-preservation or manual crystal handling in conventional crystallography experiments. We present and compare three protein structures that were solved using small crystals with dimensions of approximately 10-20 &#181;m grown in chip. By crystallizing and diffracting in situ, handling and hence mechanical disturbances of fragile crystals is minimized. The protocol details how to fabricate a custom X-ray transparent microfluidic chip suitable for in situ serial crystallography. As almost every crystal can be used for diffraction data collection, these microfluidic chips are a very efficient crystal delivery method.

Microfluidic Chips for In Situ Crystal X-ray Diffraction and In Situ Dynamic Light Scattering for Serial Crystallography

This protocol describes in detail how to fabricate and operate microfluidic devices for X-ray diffraction data collection at room temperature. Additionally, it describes how to monitor protein crystallization by dynamic light scattering and how to process and analyze obtained diffraction data.

Chip microfluidici per dispersione della luce dinamica In Situ diffrazione di raggi x di cristallo ed In Situ per la cristallografia seriale

This protocol describes fabricating microfluidic devices with low X-ray background optimized for goniometer based fixed target serial crystallography. The ...

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization

We present a pump-probe method for preparing vibrational coherences in polyatomic radical cations and probing their ultrafast dynamics. By shifting the wavelength of the strong-field ionizing pump pulse from the commonly used 800 nm into the near-infrared (1200-1600 nm), the contribution of adiabatic electron tunneling to the ionization process increases relative to multiphoton absorption. Adiabatic ionization results in predominant population of the ground electronic state of the ion upon electron removal, which effectively prepares a coherent vibrational state (&#34;wave packet&#34;) amenable to subsequent excitation. In our experiments, the coherent vibrational dynamics are probed with a weak-field 800 nm pulse and the time-dependent yields of dissociation products measured in a time-of-flight mass spectrometer. We present the measurements on the molecule dimethyl methylphosphonate (DMMP) to illustrate how using 1500 nm pulses for excitation enhances the amplitude of coherent oscillations in ion yields by a factor of 10 as compared to 800 nm pulses. This protocol may be implemented in existing pump-probe setups through the incorporation of an optical parametric amplifier (OPA) for wavelength conversion.

We present a protocol for probing ultrafast vibrational coherences in polyatomic radical cations that result in molecular dissociation.

Misurazione di coerenze ultraveloce vibrazionale in cationi poliatomici radicale con ionizzazione adiabatico del forte-campo

We present a pump-probe method for preparing vibrational coherences in polyatomic radical cations and probing their ultrafast dynamics. By shifting the ...

Automation of a Positron-emission Tomography (PET) Radiotracer Synthesis Protocol for Clinical Production

The development of new positron-emission tomography (PET) tracers is enabling researchers and clinicians to image an increasingly wide array of biological targets and processes. However, the increasing number of different tracers creates challenges for their production at radiopharmacies. While historically it has been practical to dedicate a custom-configured radiosynthesizer and hot cell for the repeated production of each individual tracer, it is becoming necessary to change this workflow. Recent commercial radiosynthesizers based on disposable cassettes/kits for each tracer simplify the production of multiple tracers with one set of equipment by eliminating the need for custom tracer-specific modifications. Furthermore, some of these radiosynthesizers enable the operator to develop and optimize their own synthesis protocols in addition to purchasing commercially-available kits. In this protocol, we describe the general procedure for how the manual synthesis of a new PET tracer can be automated on one of these radiosynthesizers and validated for the production of clinical-grade tracers. As an example, we use the ELIXYS radiosynthesizer, a flexible cassette-based radiochemistry tool that can support both PET tracer development efforts, as well as routine clinical probe manufacturing on the same system, to produce [18F]Clofarabine ([18F]CFA), a PET tracer to measure in vivo deoxycytidine kinase (dCK) enzyme activity. Translating a manual synthesis involves breaking down the synthetic protocol into basic radiochemistry processes that are then translated into intuitive chemistry &#34;unit operations&#34; supported by the synthesizer software. These operations can then rapidly be converted into an automated synthesis program by assembling them using the drag-and-drop interface. After basic testing, the synthesis and purification procedure may require optimization to achieve the desired yield and purity. Once the desired performance is achieved, a validation of the synthesis is carried out to determine its suitability for the production of the radiotracer for clinical use.

Automation of a Positron-emission Tomography PET Radiotracer Synthesis Protocol for Clinical Production

Positron-emission tomography (PET) imaging sites that are involved in multiple early clinical research trials need robust and versatile radiotracer manufacturing capabilities. Using the radiotracer [18F]Clofarabine as an example, we illustrate how to automate the synthesis of a radiotracer using a flexible, cassette-based radiosynthesizer and validate the synthesis for clinical use.

Automazione di un positrone-emissione di positroni (PET) radiotraccitore sintesi protocollo per la produzione di clinica

The development of new positron-emission tomography (PET) tracers is enabling researchers and clinicians to image an increasingly wide array of biological ...

Light-driven Molecular Motors on Surfaces for Single Molecular Imaging

The design and synthesis of a synthetic system that aims for the direct visualization of a synthetic rotary motor at the single molecule level on surfaces are demonstrated. This work requires careful design, considerable synthetic effort, and proper analysis. The rotary motion of the molecular motor in solution is shown by 1H NMR and UV-vis absorption spectroscopy techniques. In addition, the method to graft the motor onto an amine-coated quartz is described. This method helps to gain more insight into molecular machines.

The manuscript describes how to synthesize and graft a molecular motor on surfaces for single molecular imaging.

Motori molecolari basati su luce sulle superfici per l'Imaging molecolare singola

The design and synthesis of a synthetic system that aims for the direct visualization of a synthetic rotary motor at the single molecule level on surfaces ...

Imaging Corrosion at the Metal-Paint Interface Using Time-of-Flight Secondary Ion Mass Spectrometry

Corrosion developed at the paint and aluminum (Al) metal-paint interface of an aluminum alloy is analyzed using time-of-flight secondary ion mass spectrometry (ToF-SIMS), illustrating that SIMS is a suitable technique to study the chemical distribution at a metal-paint interface. The painted Al alloy coupons are immersed in a salt solution or exposed to air only. SIMS provides chemical mapping and 2D molecular imaging of the interface, allowing direct visualization of the morphology of the corrosion products formed at the metal-paint interface and mapping of the chemical after corrosion occurs. The experimental procedure of this method is presented to provide technical details to facilitate similar research and highlight pitfalls that may be encountered during such experiments.

Time-of-flight secondary ion mass spectrometry is applied to demonstrate the chemical mapping and corrosion morphology at the metal-paint interface of an aluminum alloy after being exposed to a salt solution compared with a specimen exposed to air.

Corrosione dell'imaging nell'interfaccia Metal-Paint con spettrometria di massa ionica secondaria a tempo di volo

Corrosion developed at the paint and aluminum (Al) metal-paint interface of an aluminum alloy is analyzed using time-of-flight secondary ion mass ...

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional &#960;-conjugate Systems

Femtosecond time-resolved stimulated Raman spectroscopy is a promising method of observing the structural dynamics of short-lived transients with near infrared (near-IR) transitions, because it can overcome the low sensitivity of spontaneous Raman spectrometers in the near-IR region. Here, we describe technical details of a femtosecond time-resolved near-IR multiplex stimulated Raman spectrometer that we have recently developed. A description of signal generation and optimization, measurement, data acquisition, and calibration and correction of recorded data is provided as well. We present an application of our spectrometer to analyze the excited-state dynamics of &#946;-carotene in toluene solution. A C=C stretch band of &#946;-carotene in the second lowest excited singlet (S2) state and the lowest excited singlet (S1) state is clearly observed in the recorded time-resolved stimulated Raman spectra. The femtosecond time-resolved near-IR stimulated Raman spectrometer is applicable to the structural dynamics of &#960;-conjugate systems from simple molecules to complex materials.

Details of signal generation and optimization, measurement, data acquisition, and data handling for a femtosecond time-resolved near-IR stimulated Raman spectrometer are described. A near infrared stimulated Raman study on the excited-state dynamics of &#946;-carotene in toluene is shown as a representative application.

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional .

Femtosecond time-resolved stimulated Raman spectroscopy is a promising method of observing the structural dynamics of short-lived transients with near ...

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis

Heteroarylation introduces heteroaryl fragments to organic molecules. Despite the numerous available reactions reported for arylation via transition metal catalysis, the literature on direct heteroarylation is scarce. The presence of heteroatoms such as nitrogen, sulfur and oxygen often make heteroarylation a challenging research field due to catalyst poisoning, product decomposition and the rest. This protocol details a highly efficient direct &#945;-C(sp3) heteroarylation of ketones under microwave irradiation. Key factors for successful heteroarylation include the use of XPhos Palladacycle Gen. 4 Catalyst, excess base to suppress side reactions and the high temperature and pressure achieved in a sealed reaction vial under microwave irradiation. The heteroarylation compounds prepared by this method were fully characterized by proton nuclear magnetic resonance spectroscopy (1H NMR), carbon nuclear magnetic resonance spectroscopy (13C NMR) and high-resolution mass spectrometry (HRMS). This methodology has several advantages over literature precedents including broad substrate scope, rapid reaction time, greener procedure and operational simplicity by eliminating the preparation of intermediates such as silyl enol ether. Possible applications for this protocol include, but are not limited to, diversity-oriented synthesis for the discovery of biologically active small molecules, domino synthesis for the preparation of natural products and ligand development for new transition metal catalytic systems.

Heteroaryl compounds are important molecules utilized in organic synthesis, medicinal and biological chemistry. A microwave-assisted heteroarylation using palladium catalysis provides a rapid and efficient method to attach heteroaryl moieties directly to ketone substrates.

Un'eteroarylazione diretta a microonde di chetoni utilizzando la catalisi metallica di transizione

Heteroarylation introduces heteroaryl fragments to organic molecules. Despite the numerous available reactions reported for arylation via transition metal ...

Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals

In this work, we describe a protocol for a novel application of hyperspectral imaging (HSI) in the analysis of luminescent lanthanide (Ln3+)-based molecular single crystals. As representative example, we chose a single crystal of the heterodinuclear Ln-based complex [TbEu(bpm)(tfaa)6] (bpm=2,2&#8217;-bipyrimidine, tfaa&#8211; =1,1,1-trifluoroacetylacetonate) exhibiting bright visible emission under UV excitation. HSI is an emerging technique that combines 2-dimensional spatial imaging of a luminescent structure with spectral information from each pixel of the obtained image. Specifically, HSI on single crystals of the [Tb-Eu] complex provided local spectral information unveiling variation of the luminescence intensity at different points along the studied crystals. These changes were attributed to the optical anisotropy present in the crystal, which results from the different molecular packing of Ln3+ ions in each one of the directions of the crystal structure. The HSI herein described is an example of the suitability of such technique for spectro-spatial investigations of molecular materials. Yet, importantly, this protocol can be easily extended for other types of luminescent materials (such as micron-sized molecular crystals, inorganic microparticles, nanoparticles in biological tissues, or labelled cells, among others), opening many possibilities for deeper investigation of structure-property relationships. Ultimately, such investigations will provide knowledge to be leveraged into the engineering of advanced materials for a wide range of applications from bioimaging to technological applications, such as waveguides or optoelectronic devices.

Here, we present a protocol to obtain luminescent hyperspectral imaging data and to analyze optical anisotropy features of lanthanide-based single crystals using a Hyperspectral Imaging System.