Name: preparation and in vitro characterization of dendrimer-based contrast agents for magnetic resonance imaging
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The financial support of the Max-Planck Society, the Turkish Ministry of National Education (PhD fellowship to S. G.), and the German Exchange Academic Service (DAAD, PhD fellowship to T. S.) are gratefully acknowledged.

1. Utarbeidelse av DCA <ol><li> Syntese av den monomere enhet 4 6. <ol><li> Syntese av 4- (4-nitrofenyl) -2- (4,7,10-tris-tert-butoksykarbonylmetyl-1,4,7,10-tetraazacyclododec-1-yl) smørsyre-tert-butylester (2). <ol><li> Oppløs (4,7-bis-tert-butoksykarbonylmetyl-1,4,7,10-tetraaza-cyclododec-1-yl) -eddiksyre-tert-butylester 1 (1,00 g, 1,94 mmol) i N, N-dimetylformamid ( DMF, 5 ml), tilsett...

<ol>
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Fremstilling av den dendrimere MRI-kontrastmiddel krever passende valg av den monomere enhet (dvs. den chelator for Gd (III)). De reduserer giftigheten av denne paramagnetisk ion, og til dato, et bredt utvalg av acykliske og makrosykliske chelatdannere tjene dette formålet 1-3. Blant disse makrocykliske DOTA-type chelatorer har den høyeste termodynamisk stabilitet og kinetisk inerte og, følgelig, er de mest foretrukne valg for fremstilling av inert MRI-kontrastmidler 1,18. Videre er de ...

Magnetic resonance imaging (MRI) er en kraftig og ikke-ioniserende avbildningsteknikk mye brukt i biomedisinsk forskning og klinisk diagnostikk på grunn av sin ikke-invasiv natur og utmerket kontrast iboende soft-vev. De mest brukte MR metoder anvender signalet som oppnås fra vannprotonene, noe som gir bilder med høy oppløsning og detaljert informasjon i vev basert på forskjeller i tetthet av vann signaler. Den signalintensitet og spesifisiteten av de MRI-eksperimenter kan bli ytterligere forbedret ved bruk av kontrastmidler (CAS). Disse er paramagnetiske eller superparamagnetiske art som påvirker den langsgående (T 1) og tverrgående (T 2) relaksasjonstider, henholdsvis 1,2. Komplekser av lantanid ion gadolinium med polyaminopolykarboksylsyre ligander er de mest brukte T 1 CAer. Gadolinium (III) forkorter T 1 avslapningtidspunktet for vannprotonene, noe som øker således signalet kontrasten i MRI-eksperimenter 3. Imidlertid er ionisk gadolinium giftig; dens størrelse er tilnærmet lik den for kalsium (II), og det alvorlig påvirker kalsium-assistert signalering i celler. Derfor er acykliske og makrocykliske chelater som anvendes for å nøytralisere denne toksisitet. Forskjellige flertannede ligander har blitt utviklet hittil, noe som resulterer i gadolinium (III) komplekser med høy termodynamisk stabilitet og kinetisk inerte en. De som er basert på 12-leddede azamacrocycle cyclen, spesielt dens tetracarboxylic derivat DOTA (1,4,7,10--1,4,7,10-tetraacetate) er de mest undersøkte og anvendte komplekser av denne CA klassen. Likevel GdDOTA-type instanser er lavmolekylære systemer, viser visse ulemper som lav kontrast effektivitet og rask renal utskillelse. Macromolecular og flerverdige instanser kan være en god løsning på disse problemene 4. Siden CA biodistribusjon er i hovedsak bestemt av sin størrelse, makromolekylære instanser vise mye lengre oppholdstider innenfor vev. Like viktig er det multivalency av disse midler resulterer i en økt lokal konsentrasjon av den monomere MR sonden (f.eks GdDOTA kompleks), i vesentlig grad forbedrer den ervervede MR-signalet og målekvaliteten. Dendrimerer er blant de mest foretrukne stillasene for fremstilling av flerverdige CAer for MRI 4,5. Disse høyt forgrenede makromolekyler med godt definerte størrelser er utsatt for forskjellige koblingsreaksjoner på overflaten. I dette arbeidet, rapporterer vi forberedelse, rensing og karakterisering av en dendrimere CA for MR består av en generasjon 4 (G4) poly (amidoamin) (PAMAM) dendrimer koblet til GdDOTA-lignende chelater (DCA). Vi beskriver syntesen av det reaktive derivat DOTA og dens kobling til PAMAM dendrimer. Ved kompleks med Gd (III), standard fysisk-kjemiske karakter procedure av DCA ble utført. Til slutt ble MRI-eksperimenter utført for å demonstrere evnen til DCA for å produsere MR-bilder med en sterkere kontrast enn de som oppnås fra lav molekylvekt CAer.

<table border="0" cellpadding="0" cellspacing="0" width="921">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Cyclen</td>
			<td style="width:275px;">CheMatech</td>
			<td style="width:136px;">C002</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">tert-Butyl bromoacetate&#160;</td>
			<td style="width:275px;">Alfa Aesar</td>
			<td style="width:136px;">A14917</td>
			<td style="width:259px;"></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:251px;">N,N-Dimethylformamide</td>
			<td style="width:275px;">Fluka</td>
			<td style="width:136px;">40248</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Potassium carbonate</td>
			<td style="width:275px;">Sigma-Aldrich</td>
			<td style="width:136px;">209619</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">4-(4-Nitrophenyl)butryic acid</td>
			<td style="width:275px;">Aldrich</td>
			<td style="width:136px;">335339</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:251px;">Thionyl chloride&#160;</td>
			<td style="width:275px;">Acros Organics</td>
			<td style="width:136px;">382662500</td>
			<td style="width:259px;">Note: Corrosive substance; toxic if inhaled</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:251px;">Bromine</td>
			<td style="width:275px;">Acros Organics</td>
			<td style="width:136px;">402841000</td>
			<td style="width:259px;">Note: causes severe skin burns, fatal if inhaled&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Diethyl ether</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Sodium sulphate</td>
			<td style="width:275px;">Acros Organics</td>
			<td style="width:136px;">196640010</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Chloroform&#160;</td>
			<td style="width:275px;">VWR Chemicals</td>
			<td style="width:136px;">22711.29</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:251px;">tert-Butyl 2,2,2-trichloroacetimidate</td>
			<td style="width:275px;">Aldrich</td>
			<td style="width:136px;">364789</td>
			<td style="width:259px;">Note: flammable substance; irritrant to skin and eyes</td>
		</tr>
		<tr height="67">
			<td height="67" style="height:67px;width:251px;">Boron trifluoride etherate</td>
			<td style="width:275px;">Acros Organics</td>
			<td style="width:136px;">174560250</td>
			<td style="width:259px;">48 % BF3. Note: Flammable substance; causes skin burns, fatal if inhaled&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Sodium bicarbonate</td>
			<td style="width:275px;">Acros Organics</td>
			<td style="width:136px;">424270010</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Ethyl-acetate</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td>For column chromatography</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">n-Hexane</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td>For column chromatography</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:251px;">Bulb-to-bulb (Kugelrohr) distillation apparatus</td>
			<td style="width:275px;">B&#252;chi</td>
			<td style="width:136px;"></td>
			<td>Model type: Glass oven B-585</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Silicagel</td>
			<td style="width:275px;">Carl Roth GmbH</td>
			<td style="width:136px;">P090.2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Methanol</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td>For column chromatography</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Dichloromethane&#160;</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td>For column chromatography</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Ethanol</td>
			<td style="width:275px;">VWR Chemicals</td>
			<td style="width:136px;">20821.296</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Ammonia</td>
			<td style="width:275px;">Acros Organics</td>
			<td style="width:136px;">428381000</td>
			<td style="width:259px;">7N Solution in Methanol</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Palladium&#160;</td>
			<td style="width:275px;">Aldrich</td>
			<td style="width:136px;">643181</td>
			<td style="width:259px;">15 % wet</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Hydrogenation apparatus PARR</td>
			<td style="width:275px;">PARR Instrument Company</td>
			<td style="width:136px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Celite 503</td>
			<td style="width:275px;">Aldrich</td>
			<td style="width:136px;">22151</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Sintered glass funnel</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Thiophosgen</td>
			<td style="width:275px;">Aldrich</td>
			<td style="width:136px;">115150</td>
			<td style="width:259px;">Note: irritrant to skin; toxic if inhaled</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Triethylamine</td>
			<td style="width:275px;">Alfa Aesar</td>
			<td style="width:136px;">A12646</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Dichloromethane&#160;</td>
			<td style="width:275px;">Acros Organics</td>
			<td style="width:136px;">348460010</td>
			<td style="width:259px;">Extra dry&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Magnetic stirrer</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">PAMAM G4 Dendrimer</td>
			<td style="width:275px;">Andrews ChemService</td>
			<td style="width:136px;">AuCS - 297</td>
			<td style="width:259px;">&#160;10 % wt. solution in MeOH</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Lipophylic Sephadex LH-20</td>
			<td style="width:275px;">Sigma</td>
			<td style="width:136px;">LH20100</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Thin-layer chromatography plates</td>
			<td style="width:275px;">Merck Millipore</td>
			<td style="width:136px;">1.05554.0001</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Formic acid</td>
			<td style="width:275px;">VWR Chemicals</td>
			<td style="width:136px;">20318.297</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Lophylizer&#160;</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:251px;">Gadollinium(III) chloride hexahydrate</td>
			<td style="width:275px;">Aldrich</td>
			<td style="width:136px;">G7532</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Sodium hydroxide</td>
			<td style="width:275px;">Acros Organics</td>
			<td style="width:136px;">134070010</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">pH meter</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:251px;">Ethylenediaminetetraacetic acid disodium salt dihydrate</td>
			<td style="width:275px;">Aldrich</td>
			<td style="width:136px;">E5134</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Mass spectrometer (ESI)</td>
			<td style="width:275px;">Agilent</td>
			<td style="width:136px;"></td>
			<td>Ion trap SL 1100&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Acetate buffer</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td>pH 5.8</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Xylenol orange</td>
			<td style="width:275px;">Aldrich</td>
			<td style="width:136px;">52097</td>
			<td>20 &#956;M in acetate buffer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Hydrophylic Sephadex G-15</td>
			<td style="width:275px;">GE Healthcare</td>
			<td style="width:136px;">17-0020-01</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:251px;">Amicon Ultra-15 Centrifugal Filter Unit</td>
			<td style="width:275px;">Merck Millipore</td>
			<td style="width:136px;">UFC900324</td>
			<td style="width:259px;">Ultracel-3 membrane (MWCO 3000)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Centrifuge</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">NMR spectrometer&#160;</td>
			<td style="width:275px;">Bruker</td>
			<td style="width:136px;"></td>
			<td style="width:259px;">Avance III 300 MHz</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Topspin</td>
			<td style="width:275px;">Bruker</td>
			<td style="width:136px;"></td>
			<td style="width:259px;">version 2.1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Combustion analysis instrument</td>
			<td style="width:275px;">EuroVector SpA</td>
			<td style="width:136px;"></td>
			<td style="width:259px;">EuroEA 3000 Elemental Analyser&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">MALDI-ToF MS instrument</td>
			<td style="width:275px;">Applied Biosystems</td>
			<td style="width:136px;"></td>
			<td style="width:259px;">Voyager-STR</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Deuteriumoxid</td>
			<td style="width:275px;">Carl Roth GmbH</td>
			<td style="width:136px;">6672.3</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">tert-Butyl alcohol</td>
			<td style="width:275px;">Carl Roth GmbH</td>
			<td style="width:136px;">AE16.1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Vortex mixer</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Norell NMR tubes</td>
			<td style="width:275px;">Deutero GmbH</td>
			<td style="width:136px;">507-HP-7</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">NMR coaxial tube</td>
			<td style="width:275px;">Deutero GmbH</td>
			<td style="width:136px;">coaxialb-5-7</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">DLS instrument</td>
			<td style="width:275px;">Malvern</td>
			<td style="width:136px;"></td>
			<td style="width:259px;">Zetasizer Nano ZS</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">0.20 &#956;m PTFE filter&#160;</td>
			<td style="width:275px;">Carl Roth GmbH</td>
			<td style="width:136px;">KC94.1</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">HEPES</td>
			<td style="width:275px;">Fisher BioReagents</td>
			<td style="width:136px;">BP310</td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Plastic tube vials</td>
			<td style="width:275px;">any source</td>
			<td style="width:136px;"></td>
			<td style="width:259px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Dotarem</td>
			<td style="width:275px;">Guerbet</td>
			<td style="width:136px;"></td>
			<td style="width:259px;">NDC 67684-2000-1</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:251px;">MRI scanner</td>
			<td style="width:275px;">Bruker</td>
			<td style="width:136px;"></td>
			<td style="width:259px;">BioSpec 70/30 USR magnet (7 T). Note: potential hazards related to high magnetic fields</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:251px;">RF coil</td>
			<td style="width:275px;">Bruker</td>
			<td style="width:136px;"></td>
			<td style="width:259px;">dual frequency volume coil (RF RES 300 1H/19F 075/040 LIN/LIN TR)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Paravision (software)</td>
			<td style="width:275px;">Bruker</td>
			<td style="width:136px;"></td>
			<td style="width:259px;">Version 5.1</td>
		</tr>
	</tbody>
</table>

preparation and in vitro characterization of dendrimer-based contrast agents for magnetic resonance imaging

Paramagnetiske komplekser av gadolinium (III) med asyklisk eller makrosykliske chelater er de mest brukte kontrastmidler (CAS) for magnetisk resonans imaging (MRI). Deres formål er å forbedre avslapning frekvensen av vann protoner i vev, og dermed øke MR bildekontrast og spesifisiteten av MR-målinger. Nåværende klinisk godkjent kontrastmidler er lavmolekylære molekyler som er raskt fjernet fra kroppen. Bruken av dendrimerer som bærere av paramagnetiske chelatorer kan spille en viktig rolle i den fremtidige utviklingen av mer effektive MRI-kontrastmidler. Nærmere bestemt, er økningen i lokale konsentrasjon av den paramagnetiske type resulterer i en høyere signal kontrast. Videre tilveiebringer dette en lengre CA vev retensjonstid på grunn av sin høye molekylvekt og størrelse. Her viser vi en praktisk fremgangsmåte for fremstilling av makromolekylære MRI-kontrastmidler basert på poly (amidoamin) (PAMAM-dendrimerer) med monomacrosykliske DOTA-type gelatorer (DOTA - 1,4,7,10--1,4,7,10-tetraacetate). Den chelaterende enheten ble tilføyd ved å utnytte reaktiviteten av isotiocyanatet (NCS) -gruppe mot aminoverflategruppene av PAMAM dendrimer å danne thiourea broer. Dendrimere produkter ble renset og analysert ved hjelp av kjernemagnetisk resonansspektroskopi, massespektrometri, og elementanalyse. Til slutt ble høyoppløselige MR-bilder registreres og signal kontrastene oppnådd fra den preparerte dendrimere og de kommersielt tilgjengelige monomere midler ble sammenlignet.

Fremstillingen av DCA besto av to trinn: 1) syntese av den monomere DOTA-type chelateringsmiddel (figur 1) og 2) kopling av chelator med G4 PAMAM dendrimer og etterfølgende fremstilling av den dendrimere Gd (III) -kompleks (Figur 2) . I det første trinn ble en cyclen basert DOTA-type chelateringsmiddel som inneholder fire karboksylsyrer og en ortogonal gruppe egnet for ytterligere syntetiske modifikasjoner fremstilt. Fremstillingen sta...

Watch this Scientific Journal Video about Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging at JoVE.com

Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging

Denne protokollen beskriver utarbeidelse og karakterisering av en dendrimere magnetic resonance imaging (MRI) kontrastmiddel som bærer cyclen-basert makrosykliske chelater koordinerende para gadolinium-ioner. I en serie av MRI-eksperimenter in vitro, blir dette middel ga en forsterket MRI-signal i forhold til de kommersielt tilgjengelige monomere analog.

forberedelse og<em&gt; In Vitro</em&gt; Karakterisering av dendrimer-baserte kontrastmidler for Magnetic Resonance Imaging

Paramagnetic complexes of gadolinium(III) with acyclic or macrocyclic chelates are the most commonly used contrast agents (CAs) for magnetic resonance ...

Research

JoVE Journal

Chemistry

Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging

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

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

Syntese, Cellular Levering og<em&gt; In vivo</em&gt; Bruk av Dendrimer-baserte pH Sensorer

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

Preparation and Characterization of SDF-1&#945;-Chitosan-Dextran Sulfate Nanoparticles

Preparation and Characterization of SDF-1ÃƒÅ½Ã‚Â±-Chitosan-Dextran Sulfate Nanoparticles

Utarbeidelse og karakterisering av SDF-1α-Chitosan-dekstransulfat Nanopartikler

Chitosan (CS) and dextran sulfate (DS) are charged polysaccharides (glycans), which form polyelectrolyte complex-based nanoparticles when mixed under ...

Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles

Utarbeidelse og karakterisering av Individuell og Multi-drug Loaded fysisk innesperret Polymer Miceller

Amphiphilic block copolymers like polyethyleneglycol-block-polylactic acid (PEG-b-PLA) can self-assemble into micelles above their critical micellar ...

Sequencing of Plant Wall Heteroxylans Using Enzymic, Chemical (Methylation) and Physical (Mass Spectrometry, Nuclear Magnetic Resonance) Techniques

Sequencing of Plant Wall Heteroxylans Using Enzymic, Chemical Methylation and Physical Mass Spectrometry, Nuclear Magnetic Resonance Techniques

Sekvensering av Plant Wall Heteroxylans Bruke enzymic, Chemical (Metylering) og fysiske (massespektrometri Nuclear Magnetic Resonance) Teknikker

This protocol describes the specific techniques used for the characterization of reducing end (RE) and internal region glycosyl sequence(s) of ...

Synthesis and Characterization of Supramolecular Colloids

Syntese og karakterisering av supra Colloids

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical ...

Low-energy Cathodoluminescence for (Oxy)Nitride Phosphors

Low-energy Cathodoluminescence for OxyNitride Phosphors

Lavenergi katodeluminisens for (Oxy) nitrid Fosfor

Nitride and oxynitride (Sialon) phosphors are good candidates for the ultraviolet and visible emission applications. High performance, good stability and ...

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging

In Situ Overvåking av Diffusion of Guest Molekyler i porøse medier Bruke Electron Paramagnetic Resonance Imaging

A method is demonstrated to monitor macroscopic translational diffusion using electron paramagnetic resonance (EPR) imaging. A host-guest system with ...

DNA-magnetic Particle Binding Analysis by Dynamic and Electrophoretic Light Scattering

DNA-magnetiske partikler bindende analyse av dynamisk og Electrophoretic lysspredning

Isolation of DNA using magnetic particles is a field of high importance in biotechnology and molecular biology research. This protocol describes the ...

Preparation and Characterization of C60/Graphene Hybrid Nanostructures

Preparation and Characterization of C60/Graphene Hybrid Nanostructures

Forberedelse og karakterisering av C60/Graphene Hybrid nanostrukturer

Physical thermal deposition in a high vacuum environment is a clean and controllable method for fabricating novel molecular nanostructures on graphene. We ...

Technical Aspect of the Automated Synthesis and Real-Time Kinetic Evaluation of [11C]SNAP-7941

Technical Aspect of the Automated Synthesis and Real-Time Kinetic Evaluation of [11C]SNAP-7941

Teknisk aspekt av automatisert syntese og Real-Time Kinetic evaluering av [11C] SNAP-7941

Positron emission tomography (PET) is an essential molecular imaging technique providing insights into pathways and using specific targeted radioligands ...