Die Autoren erkennen an, Saudi-Arabien finanzierte Stipendium (I821) für die Herstellung der Forschung möglich. Die Autoren danken Dr. Xianwei Liu für kompetente Unterstützung bei TEM-Analyse an der Cranfield University.

1. Herstellung der Öl-in-Wasser-Emulsion <ol><li> Wiegen Glycerylpalmitostearat (120 mg), Isopropylmyristat (60 mg), d-α-Tocopheryl-Polyethylenglykol-Succinat (30 mg) und Sojabohnen-Lecithin (30 mg), und diese in 12,5 ml von organischen Lösungsmitteln (6,25 ml Aceton und 6,25 ml Ethanol). Schnell das Gemisch bei der Temperatur 70 ° C (5 ° C über dem Schmelzpunkt des festen Lipids) in Wasserbad auflösen. </li><li> Fügen entweder 125, 250 oder 375 mg Poloxamer188 in 12,5 ml ddH 2 O 1-3% (jeweils) von Poloxamer 188 - Lösung zu erreichen, die wie oben dem Erhitzen bei der gleichen Temperatur ausgesetzt ist. </li><li> Fügen Sie die wässrige Phase Lösung aus Schritt 1.2 zu der Ölphasenlösung aus Schritt 1.1 tropfenweise Emulsionen unter magnetischem Rühren bei 400 UpM zu bilden. Rühren Sie die Emulsion bei 400 rpm für weitere 4 h Verdampfung der organischen Lösungsmittel zu ermöglichen. </li></ol> 2. Erstarren und Homogenisieren <ol><li> Lassen Sie ter Emulsion in einem Kühlraum (4 ° C) für 2 Stunden zur Verfestigung / kristallisieren. </li><li> Zur Erzielung NLC, unterziehen die Emulsion zu hohen blossen Dispersion (HSD) mit einem Homogenisator bei 10.000-15.000 rpm für 10-40 min. </li></ol> 3. Optimierung der NLC Vorbereitung <ol><li> Proben zu entnehmen, aus dem Schritt 2.2 mit einer Tensidkonzentration von 1, 2 und 3% unterzieht HSD bei Geschwindigkeiten von 10.000, 15.000 und 20.000 Umdrehungen pro Minute bzw. und Zeitintervallen von 10, 20, 30 und 40 min, </li><li> Überprüfen Sie die Proben für die Partikelgröße (PS), Poly Dispersionsindex (PDI), Morphologie und Ultrastruktur 20. Hinweis: Die Parameter, die Partikel mit der kleinsten Größe (155 nm) und PDI (0,2) Wert erzeugen, werden als optimal bestimmt. </li></ol> 4. Herstellung von Dac belasteten NLC (NLC-Dac) <ol><li> Bereiten Ölphasenlösung, wie in Schritt 1.1 mit der Zugabe von Dac (70 mg) beschrieben, bevor die Mischung bei 70 ° C in einem Wasserbad aufgelöst. </li><li> Prepare eine wässrige Phase Lösung, wie in Schritt 1.2 mit 1% Tensid beschrieben, und fügen diese Lösung zu dem in Schritt 4.1 tropfenweise vorbereitet bei 400 rpm eine Emulsion unter magnetischem Rühren zu bilden. Rühren Sie die Emulsion für weitere 4 Stunden die organischen Lösungsmittel zu verdampfen. </li><li> Verlassen die Emulsion in einem Kühlraum (4 ° C) für 2 Stunden zur Verfestigung / kristallisieren, wie in Schritt 2 beschrieben ist, und schließlich die Emulsion zu unterziehen hoher Scherung Dispersion (HSD) bestimmt, um die optimalen Parameter unter Verwendung der in Schritt 3. </li></ol>

<ol>
	<li>Loo, T. L., Housholder, G. E., Gerulath, A. H., Saunders, P. H., Farquhar, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanism+of+action+and+pharmacology+studies+with+DTIC+(NSC+45388).">Mechanism of action and pharmacology studies with DTIC (NSC 45388).</a> Cancer Treat Rep. 60 (2), 149-152 (1976).</li><li>Behringer, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Omission+of+dacarbazine+or+bleomycin,+or+both,+from+the+ABVD+regimen+in+treatment+of+early-stage+favourable+Hodgkin's+lymphoma+(GHSG+HD13):+An+open-label,+randomised,+non-inferiority+trial.">Omission of dacarbazine or bleomycin, or both, from the ABVD regimen in treatment of early-stage favourable Hodgkin's lymphoma (GHSG HD13): An open-label, randomised, non-inferiority trial.</a> The Lancet. 385 (9976), 1418-1427 (2014).</li><li>Carvajal, R. 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+phase+2+randomised+study+of+ramucirumab+(IMC-1121B)+with+or+without+dacarbazine+in+patients+with+metastatic+melanoma.">A phase 2 randomised study of ramucirumab (IMC-1121B) with or without dacarbazine in patients with metastatic melanoma.</a> Eur J Cancer. 50 (12), 2099-2107 (2014).</li><li>Jiang, G., Li, R., Sun, C., Liu, Y., Zheng, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dacarbazine+combined+targeted+therapy+versus+dacarbazine+alone+in+patients+with+malignant+melanoma:+A+meta-analysis.">Dacarbazine combined targeted therapy versus dacarbazine alone in patients with malignant melanoma: A meta-analysis.</a> PLoS ONE. 9 (12), (2014).</li><li>Lazar, V., 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=Sorafenib+plus+dacarbazine+in+solid+tumors:+A+phase+i+study+with+dynamic+contrast-enhanced+ultrasonography+and+genomic+analysis+of+sequential+tumor+biopsy+samples.">Sorafenib plus dacarbazine in solid tumors: A phase i study with dynamic contrast-enhanced ultrasonography and genomic analysis of sequential tumor biopsy samples.</a> Invest New Drugs. 32 (2), 312-322 (2014).</li><li>Niemeijer, N. D., Alblas, G., Van Hulsteijn, L. T., Dekkers, O. M., Corssmit, E. P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemotherapy+with+cyclophosphamide,+vincristine+and+dacarbazine+for+malignant+paraganglioma+and+pheochromocytoma:+Systematic+review+and+meta-analysis.">Chemotherapy with cyclophosphamide, vincristine and dacarbazine for malignant paraganglioma and pheochromocytoma: Systematic review and meta-analysis.</a> Clin Endocrinol (Oxf). 81 (5), 642-651 (2014).</li><li>Bedikian, A. Y., Garbe, C., Conry, R., Lebbe, C., Grob, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dacarbazine+with+or+without+oblimersen+(a+Bcl-2+antisense+oligonucleotide)+in+chemotherapy-naive+patients+with+advanced+melanoma+and+low-normal+serum+lactate+dehydrogenase:+'The+AGENDA+trial'.">Dacarbazine with or without oblimersen (a Bcl-2 antisense oligonucleotide) in chemotherapy-naive patients with advanced melanoma and low-normal serum lactate dehydrogenase: 'The AGENDA trial'.</a> Melanoma Res. 24 (3), 237-243 (2014).</li><li>Daponte, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phase+III+randomized+study+of+fotemustine+and+dacarbazine+versus+dacarbazine+with+or+without+interferon-a+in+advanced+malignant+melanoma.">Phase III randomized study of fotemustine and dacarbazine versus dacarbazine with or without interferon-a in advanced malignant melanoma.</a> J Trans Med. 11 (1), (2013).</li><li>Jiao, J., Rhodes, D. G., Burgess, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiple+Emulsion+Stability:+Pressure+Balance+and+Interfacial+Film+Strength.">Multiple Emulsion Stability: Pressure Balance and Interfacial Film Strength.</a> J Colloid Interface Sci. 250 (2), 444-450 (2002).</li><li>Kakumanu, S., Tagne, J. B., Wilson, T. A., Nicolosi, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+nanoemulsion+formulation+of+dacarbazine+reduces+tumor+size+in+a+xenograft+mouse+epidermoid+carcinoma+model+compared+to+dacarbazine+suspension.">A nanoemulsion formulation of dacarbazine reduces tumor size in a xenograft mouse epidermoid carcinoma model compared to dacarbazine suspension.</a> Nanomedicine. 7 (3), 277-283 (2011).</li><li>Xie, T., Nguyen, T., Hupe, M., Wei, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multidrug+resistance+decreases+with+mutations+of+melanosomal+regulatory+genes.">Multidrug resistance decreases with mutations of melanosomal regulatory genes.</a> Cancer Res. 69 (3), 992-999 (2009).</li><li>Estanqueiro, M., Amaral, M. H., Concei&#231;&#227;o, J., Lobo, J. M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanotechnological+carriers+for+cancer+chemotherapy:+the+state+of+the+art.">Nanotechnological carriers for cancer chemotherapy: the state of the art.</a> Colloids Surf., B. 126, 631-648 (2015).</li><li>Koziara, J. M., Whisman, T. R., Tseng, M. T., Mumper, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In-vivo+efficacy+of+novel+paclitaxel+nanoparticles+in+paclitaxel-resistant+human+colorectal+tumors.">In-vivo efficacy of novel paclitaxel nanoparticles in paclitaxel-resistant human colorectal tumors.</a> J Controlled Release. 112 (3), 312-319 (2006).</li><li>Ding, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biodegradable+methoxy+poly+(ethylene+glycol)-poly+(lactide)+nanoparticles+for+controlled+delivery+of+dacarbazine:+Preparation,+characterization+and+anticancer+activity+evaluation.">Biodegradable methoxy poly (ethylene glycol)-poly (lactide) nanoparticles for controlled delivery of dacarbazine: Preparation, characterization and anticancer activity evaluation.</a> Afr J Pharm Pharacol. 5 (11), 1369-1377 (2011).</li><li>Ding, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anti-DR5+monoclonal+antibody-mediated+DTIC-loaded+nanoparticles+combining+chemotherapy+and+immunotherapy+for+malignant+melanoma:+target+formulation+development+and+in+vitro+anticancer+activity.">Anti-DR5 monoclonal antibody-mediated DTIC-loaded nanoparticles combining chemotherapy and immunotherapy for malignant melanoma: target formulation development and in vitro anticancer activity.</a> Int J Nanomedicine. 6, 1991-2005 (2011).</li><li>Jenning, V., Th&#252;nemann, A. F., Gohla, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterisation+of+a+novel+solid+lipid+nanoparticle+carrier+system+based+on+binary+mixtures+of+liquid+and+solid+lipids.">Characterisation of a novel solid lipid nanoparticle carrier system based on binary mixtures of liquid and solid lipids.</a> Int J Pharm. 199 (2), 167-177 (2000).</li><li>M&#252;ller, R. H., Radtke, M., Wissing, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanostructured+lipid+matrices+for+improved+microencapsulation+of+drugs.">Nanostructured lipid matrices for improved microencapsulation of drugs.</a> Int J Pharm. 242 (1-2), 121-128 (2002).</li><li>Pouton, C. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lipid+formulations+for+oral+administration+of+drugs:+Non-emulsifying,+self-emulsifying+and+'self-microemulsifying'+drug+delivery+systems.">Lipid formulations for oral administration of drugs: Non-emulsifying, self-emulsifying and 'self-microemulsifying' drug delivery systems.</a> Eur. J. Pharm. Sci. 11 (Suppl. 2), S93-S98 (2000).</li><li>Jores, K., Mehnert, W., Drechsler, M., Bunjes, H., Johann, C., M&#228;der, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigations+on+the+structure+of+solid+lipid+nanoparticles+(SLN)+and+oil-loaded+solid+lipid+nanoparticles+by+photon+correlation+spectroscopy,+field-flow+fractionation+and+transmission+electron+microscopy.">Investigations on the structure of solid lipid nanoparticles (SLN) and oil-loaded solid lipid nanoparticles by photon correlation spectroscopy, field-flow fractionation and transmission electron microscopy.</a> J Controlled Release. 95 (2), 217-227 (2004).</li><li>Almousallam, M., Zhu, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Encapsulation+of+cancer+therapeutic+agent+dacarbazine+using+nanostructured+lipid+carrier.">Encapsulation of cancer therapeutic agent dacarbazine using nanostructured lipid carrier.</a> Int nano lett. , (2015).</li><li>Ng, W. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thymoquinone-loaded+nanostructured+lipid+carrier+exhibited+cytotoxicity+towards+breast+cancer+cell+lines+(MDA-MB-231+and+MCF-7)+and+cervical+cancer+cell+lines+(HeLa+and+SiHa).">Thymoquinone-loaded nanostructured lipid carrier exhibited cytotoxicity towards breast cancer cell lines (MDA-MB-231 and MCF-7) and cervical cancer cell lines (HeLa and SiHa).</a> BioMed Research International. , (2015).</li><li>Sun, M., 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=Quercetin-nanostructured+lipid+carriers:+Characteristics+and+anti-breast+cancer+activities+in+vitro.">Quercetin-nanostructured lipid carriers: Characteristics and anti-breast cancer activities in vitro.</a> Colloids Surf., B. 113, 15-24 (2014).</li><li>Savla, R., Garbuzenko, O. B., Chen, S., Rodriguez-Rodriguez, L., Minko, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor-Targeted+Responsive+Nanoparticle-Based+Systems+for+Magnetic+Resonance+Imaging+and+Therapy.">Tumor-Targeted Responsive Nanoparticle-Based Systems for Magnetic Resonance Imaging and Therapy.</a> Pharm Res. 31 (12), 3487-3502 (2014).</li><li>Chen, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formulation,+characterization,+and+evaluation+of+in+vitro+skin+permeation+and+in+vivo+pharmacodynamics+of+surface-charged+tripterine-loaded+nanostructured+lipid+carriers.">Formulation, characterization, and evaluation of in vitro skin permeation and in vivo pharmacodynamics of surface-charged tripterine-loaded nanostructured lipid carriers.</a> Int J Nanomedicine. 7, 3023 (2012).</li><li>Sanna, V., Caria, G., Mariani, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+lipid+nanoparticles+containing+fatty+alcohols+having+different+chain+length+on+the+ex+vivo+skin+permeability+of+Econazole+nitrate.">Effect of lipid nanoparticles containing fatty alcohols having different chain length on the ex vivo skin permeability of Econazole nitrate.</a> Powder Technol. 201 (1), 32-36 (2010).</li><li>Brigger, I., Dubernet, C., Couvreur, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoparticles+in+cancer+therapy+and+diagnosis.">Nanoparticles in cancer therapy and diagnosis.</a> Adv Drug Deliv Rev. 54 (5), 631-651 (2002).</li><li>Visaria, R. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhancement+of+tumor+thermal+therapy+using+gold+nanoparticle-assisted+tumor+necrosis+factor-a+delivery.">Enhancement of tumor thermal therapy using gold nanoparticle-assisted tumor necrosis factor-a delivery.</a> Mol Cancer Ther. 5 (4), 1014-1020 (2006).</li><li>Tripathi, A., Gupta, R., Saraf, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=PLGA+nanoparticles+of+anti+tubercular+drug:+Drug+loading+and+release+studies+of+a+water+in-soluble+drug.">PLGA nanoparticles of anti tubercular drug: Drug loading and release studies of a water in-soluble drug.</a> Int J PharmTech Res. 2 (3), 2116-2123 (2010).</li><li>Joshi, M., Patravale, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanostructured+lipid+carrier+(NLC)+based+gel+of+celecoxib.">Nanostructured lipid carrier (NLC) based gel of celecoxib.</a> Int J Pharm. 346 (1-2), 124-132 (2008).</li><li>Lim, W. M., Rajinikanth, P. S., Mallikarjun, C., Kang, Y. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formulation+and+delivery+of+itraconazole+to+the+brain+using+a+nanolipid+carrier+system.">Formulation and delivery of itraconazole to the brain using a nanolipid carrier system.</a> Int J Nanomedicine. 9 (1), 2117-2126 (2014).</li><li>Bei, D., Zhang, T., Murowchick, J. B., Youan, B. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formulation+of+dacarbazine-loaded+cubosomes.+Part+III.+physicochemical+characterization.">Formulation of dacarbazine-loaded cubosomes. Part III. physicochemical characterization.</a> AAPS PharmSciTech. 11 (3), 1243-1249 (2010).</li><li>Lei, M., 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=Dual+drug+encapsulation+in+a+novel+nano-vesicular+carrier+for+the+treatment+of+cutaneous+melanoma:+Characterization+and+in+vitro/in+vivo+evaluation.">Dual drug encapsulation in a novel nano-vesicular carrier for the treatment of cutaneous melanoma: Characterization and in vitro/in vivo evaluation.</a> RSC Advances. 5 (26), (2015).</li></ol>

Die Autoren haben nichts zu offenbaren.

Lipid-basierte nanostrukturierten Partikel wurden, um eine stark lipophile Träger für die Abgabe von hydrophoben Arzneimitteln zur Verfügung zu stellen verwendet. Ein NLC ist die zweite Generation von festen Lipidnanostrukturierten Träger, die bei Raum- und Körpertemperatur fest sind. Die Einarbeitung eines festen Lipids in einer flüssigen Lipid in einem NLC führt zu einer weniger perfekten Kristallisation, wodurch die Erhöhung der Arzneimittelbeladungseffizienz und die Austreibung von eingekapselten Medikamente...

Dacarbazin (Dac) ein Alkylierungsmittel , die anti-Tumoraktivität durch Nukleinsäuren Methylierung oder direkte DNA damage 1, was zu Zellzyklusarrest und Zelltod ausübt. Als erste chemotherapeutische Mittel hat Dac allein oder in Kombination mit anderen Chemotherapeutika wurden 2-6 zur Behandlung verschiedener Krebsarten verwendet. Es ist das am meisten Wirkstoff bisher bei der Behandlung von Haut- und des metastasierenden Melanoms verwendet, die die aggressivste Form von Hautkrebs 3,7,8 ist. Die Reaktionsrate, jedoch nur 20% am besten, und die therapeutischen Effekte sind häufig mit schweren systemischen Nebenwirkungen begleitet. In seiner natürlichen Form ist Dac hydrophil und ist instabil aufgrund seiner Lichtempfindlichkeit 9. Die einzige verfügbare Formel für die klinische Verwendung ist derzeit ein steriles Pulver zur intravenösen Infusion 7,8 in Suspension eingesetzt werden. Die niedrige Ansprechrate und hohe systemische Toxizität raß des Medikaments ist im Wesentlichen auf seine schlechte Wasserlöslichkeit, daher geringe Verfügbarkeit bei Zielort und eine hohe Verteilung an Nicht-Zielstellen, die die maximale Dosis des Medikaments begrenzt 10. Der schnelle Abbau und Stoffwechsel nach der intravenösen Aufnahme zusammen mit der Entwicklung von Medikamentenresistenz begrenzen die klinische Anwendung und therapeutische Wirkung des Medikaments 11. Daher besteht ein dringender Bedarf für die Behandlung von malignem Melanom alternative Dac-Formulierungen zu entwickeln. Kolloidale Systeme , die Liposomen, Mizellen oder nanostrukturierte Partikel wurden für ihre Verwendung im Bereich Drug Delivery intensiv untersucht , wie von Marilene prüft et al. 12 Nanostrukturierte Partikel als potentielle Arzneimittelträger anzieht wurden in den letzten zehn Jahren aufgrund ihrer Fähigkeit , zunehmende Aufmerksamkeit Wirkstoffbeladung zu erhöhen Effizienz, Kontrolle Arzneimittelfreisetzung, zur Verbesserung der Arzneimittel Pharmakokinetik und Bioverteilung und daher reduce Medikament systemische Toxizität 13. Nur wenige Nanoformulierungen haben jedoch bisher für Dac Lieferung sucht des Arzneimittels aus photo - Degeneration, erhöhter Arzneimittellöslichkeit und eine verbesserte therapeutische Wirkung 10,14,15 zeigt Schutz. Allerdings sind diese Formulierungen litt unter niedrigem Einkapseln Effizienz, während einige auch synthetische Polymer-Nanopartikel verwenden, die nicht kosteneffektiv sind. Nanostrukturierte Lipidträger (NLC), die aus einer Mischung von festen und flüssigen Lipiden, wurden für die Arzneimittelabgabe 16,17 entwickelt. Die Medikamente gekapselt werden oft löslich sowohl in den flüssigen Lipiden und Lipiden feste Phasen 18, was zu einer hohen Belastung und kontrollierte Freisetzung 19. Diese Studie zielt darauf ab, eine neue Dac Formulierung basierend auf NLC-Verkapselung mit Glycerylpalmitostearat und Isopropylmyristat als Lipide zu entwickeln. Die Herstellung beteiligt Öl-in-Wasser-Emulsion, Verdunstung, Verfestigung und homogenization. Die Vorbereitungen wurden für die NLC Größe, Form, Ultrastruktur, und die Dispersität, Drogen Verkapselungswirksamkeit und Wirkstoffbeladung 20 gekennzeichnet.

<table><tbody><tr><td>Dacarbazine (DAC)</td><td>Sigma Aldrich (Gillingham Dorset, UK)</td><td>D2390-100MG</td><td>drug used for uploading</td></tr><tr><td>glyceryl palmitostearate&amp;nbsp;</td><td>Gattefoss&amp;eacute; (Saint_Priest_c&amp;eacute;dex, France)</td><td>85251-77-0</td><td>solid lipid&amp;nbsp;</td></tr><tr><td>d-&amp;alpha;- Tocopherol polyethylene glycol succinate (TPGS)</td><td>Sigma Aldrich (Gillingham Dorset, UK)</td><td>57668</td><td>lipid phase surfactant</td></tr><tr><td>Poloxamer 188</td><td>Sigma Aldrich (Gillingham Dorset, UK)</td><td>15759-1KG</td><td>liqiud phase surfactant</td></tr><tr><td>Acetone&amp;nbsp;</td><td>Sigma Aldrich (Gillingham Dorset, UK)</td><td>650501-1L</td><td>organic solvent</td></tr><tr><td>Ethanol&amp;nbsp;</td><td>Sigma Aldrich (Gillingham Dorset, UK)</td><td>459836-1L</td><td>organic solvent</td></tr><tr><td>Soybean lecithin (SL)</td><td>Cuisine Innovation (Dijon, France)</td><td>SLL1402</td><td>lipid phase surfactant</td></tr><tr><td>Double-distilled water was collected in our laboratory from</td><td>Millipore-Q Gradient A10 ultra-pure water system (Millipore, France)</td><td>SAS - 67120&amp;nbsp;</td><td>aqueous phase&amp;nbsp;</td></tr><tr><td>T 25 digital ULTRA-TURRAX</td><td>IKA</td><td>3725000</td><td>as high shear disperser</td></tr><tr><td>Hotplate Magnetic Stirrer</td><td>Scientific Support, Inc</td><td>1454&amp;nbsp;</td><td>emulsion homogenization</td></tr></tbody></table>

encapsulation of cancer therapeutic agent dacarbazine using nanostructured lipid carrier

Die einzige Formel Dacarbazin (Dac) in der klinischen Anwendung ist die intravenöse Infusion, eine schlechte therapeutisches Profil aufgrund der geringen Dispersität des Arzneimittels in wässriger Lösung vor. Um dies zu überwinden, wird eine nanostrukturierte Lipidträger (NLC), bestehend aus Glycerylpalmitostearat und Isopropylmyristat wurde entwickelt Dac zu verkapseln. NLCs mit kontrollierter Größe wurden unter Verwendung hoher Scherdispersion (HSD) nach dem Erstarren von Öl-in-Wasser-Emulsion erreicht wird. Die Syntheseparameter, einschließlich der Tensidkonzentration, die Geschwindigkeit und die Zeit des HSD optimiert wurden die kleinste NLC mit Größe, Polydispersionsindex und Zeta-Potential von 155 ± 10 nm zu erreichen, 0,2 ± 0,01, und -43,4 ± 2 mV, respectively. Die optimalen Parameter wurden auch für Dac belastete NLC Zubereitung eingesetzt. Die resultierende NLC mit Dac geladen besaß Größe, Polydispersitätsindex und Zetapotential von 190 ± 10 nm, 0,2 ± 0,01, und -43,5 ± 1,2 mV sind. Die Wirkstoffverkapselung efzienz und Wirkstoffbeladung erreicht 98% und 14% betragen. Dies ist der erste Bericht über die Verkapselung von Dac mit NLC, was impliziert, dass NLC ein neuer potentieller Kandidat als Arzneimittelträger sein könnte, das therapeutische Profil von Dac zu verbessern.

Die Präparate der NLC und NLC-Dac Verwendung Glycerylpalmitostearat und Isopropylmyristat mit verschiedenen Parametern wurden für PS, PDI, Morphologie und Ultrastruktur 20 aus. Die PS und PDI der NLCs waren Tensidkonzentration, HSD Geschwindigkeit und Dauer abhängig. Wie beurteilt durch PS und PDI der NLCs, wurden die besten Ergebnisse mit 1% Tensid und eine reine Dispersionsgeschwindigkeit von 15000 Upm für NLC für 30 min (1A, B und <str...

Watch this Scientific Journal Video about Encapsulation of Cancer Therapeutic Agent Dacarbazine Using Nanostructured Lipid Carrier at JoVE.com

Encapsulation of Cancer Therapeutic Agent Dacarbazine Using Nanostructured Lipid Carrier

Das am häufigsten verwendete Verfahren für nanostrukturierte Lipidträger (NLC) Synthese beinhaltet Öl-in-Wasser-Emulsion, Homogenisieren und Erstarren. Dies wurde hier modifiziert durch hohe Scherdispersion nach der Verfestigung Aufbringen einer NLC mit erwünschten Größe, verbesserte Wirkstoffverkapselung und Wirkstoffbeladung Effizienz als potenzielle Träger für Dacarbazin Lieferung zu erreichen.

Verkapselung von Krebstherapeutikum Dacarbazin Verwendung von Nanostrukturierte Lipid-Träger

The only formula of dacarbazine (Dac) in clinical use is intravenous infusion, presenting a poor therapeutic profile due to the low dispersity of the drug ...

encapsulation-cancer-therapeutic-agent-dacarbazine-using

Research

JoVE Journal

Chemistry

11.0K Aufrufe.  Cranfield University.  Das am häufigsten verwendete Verfahren für nanostrukturierte Lipidträger (NLC) Synthese beinhaltet Öl-in-Wasser-Emulsion, Homogenisieren und Erstarren. Dies wurde hier modifiziert durch hohe Scherdispersion nach der Verfestigung Aufbringen einer NLC mit erwünschten Größe, verbesserte Wirkstoffverkapselung und Wirkstoffbeladung Effizienz als potenzielle Träger für Dacarbazin Lieferung zu erreichen. 

Serie: Encapsulation of Cancer Therapeutic Agent Dacarbazine Using Nanostructured Lipid Carrier

A Facile and Efficient Approach for the Production of Reversible Disulfide Cross-linked Micelles

Nanomedicine is an emerging form of therapy that harnesses the unique properties of particles that are nanometers in scale for biomedical application. Improving drug delivery to maximize therapeutic outcomes and to reduce drug-associated side effects are some of the cornerstones of present-day nanomedicine. Nanoparticles in particular have found a wide application in cancer treatment. Nanoparticles that offer a high degree of flexibility in design, application, and production based on the tumor microenvironment are projected to be more effective with rapid translation into clinical practice. The polymeric micellar nano-carrier is a popular choice for drug delivery applications.
In this article, we describe a simple and effective protocol for synthesizing drug-loaded, disulfide cross-linked micelles based on the self-assembly of a well-defined amphiphilic linear-dendritic copolymer (telodendrimer, TD). TD is composed of polyethylene glycol (PEG) as the hydrophilic segment and a thiolated cholic acid cluster as the core-forming hydrophobic moiety attached stepwise to an amine-terminated PEG using solution-based peptide chemistry. Chemotherapy drugs, such as paclitaxel (PTX), can be loaded using a standard solvent evaporation method. The O2-mediated oxidation was previously utilized to form intra-micellar disulfide cross-links from free thiol groups on the TDs. However, the reaction was slow and not feasible for large-scale production. Recently, an H2O2-mediated oxidation method was explored as a more feasible and efficient approach, and it was 96 times faster than the previously reported method. Using this approach, 50 g of PTX-loaded, disulfide cross-linked nanoparticles have been successfully produced with narrow particle size distribution and high drug loading efficiency. The stability of the resulting micelle solution is analyzed using disrupting conditions such as co-incubation with a detergent, sodium dodecyl sulfate, with or without a reducing agent. The drug-loaded, disulfide cross-linked micelles demonstrated less hemolytic activity when compared to their non-cross-linked counterparts.

To deliver cancer drugs to tumor sites with high specificity and reduced side effects, new methods based on nanoparticles are required. Here, we describe disulfide cross-linked micelles that can be easily prepared by hydrogen peroxide-mediated oxidation and are able to dissociate efficiently under a reducing tumor environment to release payloads.

Eine leichte und effiziente Ansatz für die Produktion von Reversible Disulfid Vernetzte Mizellen

Nanomedicine is an emerging form of therapy that harnesses the unique properties of particles that are nanometers in scale for biomedical application. ...

Forschung

Biochemie

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

Amphiphilic block copolymers like polyethyleneglycol-block-polylactic acid (PEG-b-PLA) can self-assemble into micelles above their critical micellar concentration forming hydrophobic cores surrounded by hydrophilic shells in aqueous environments. The core of these micelles can be utilized to load hydrophobic, poorly water soluble drugs like docetaxel (DTX) and everolimus (EVR). Systematic characterization of the micelle structure and drug loading capabilities are important before in vitro and in vivo studies can be conducted. The goal of the protocol described herein is to provide the necessary characterization steps to achieve standardized micellar products. DTX and EVR have intrinsic solubilities of 1.9 and 9.6 &#181;g/ml respectively Preparation of these micelles can be achieved through solvent casting which increases the aqueous solubility of DTX and EVR to 1.86 and 1.85 mg/ml, respectively. Drug stability in micelles evaluated at room temperature over 48 hr indicates that 97% or more of the drugs are retained in solution. Micelle size was assessed using dynamic light scattering and indicated that the size of these micelles was below 50 nm and depended on the molecular weight of the polymer. Drug release from the micelles was assessed using dialysis under sink conditions at pH 7.4 at 37 oC over 48 hr. Curve fitting results indicate that drug release is driven by a first order process indicating that it is diffusion driven.

The goal of this protocol is to describe the preparation and characterization of physically entrapped, poorly water soluble drugs in micellar drug delivery systems composed of amphiphilic block copolymers.

Herstellung und Charakterisierung von Einzel-und Multi-Wirkstoff beladen Körperlich Eingeschlossene Polymermicellen

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

Chemie

Facile Preparation of Internally Self-assembled Lipid Particles Stabilized by Carbon Nanotubes

We present a facile method to prepare nanostructured lipid particles stabilized by carbon nanotubes (CNTs). Single-walled (pristine) and multi-walled (functionalized) CNTs are used as stabilizers to produce Pickering type oil-in-water (O/W) emulsions. Lipids namely, Dimodan U and Phytantriol are used as emulsifiers, which in excess water self-assemble into the bicontinuous cubic Pn3m phase. This highly viscous phase is fragmented into smaller particles using a probe ultrasonicator in presence of conventional surfactant stabilizers or CNTs as done here. Initially, the CNTs (powder form) are dispersed in water followed by further ultrasonication with the molten lipid to form the final emulsion. During this process the CNTs get coated with lipid molecules, which in turn are presumed to surround the lipid droplets to form a particulate emulsion that is stable for months. The average size of CNT-stabilized nanostructured lipid particles is in the submicron range, which compares well with the particles stabilized using conventional surfactants. Small angle X-ray scattering data confirms the retention of the original Pn3m cubic phase in the CNT-stabilized lipid dispersions as compared to the pure lipid phase (bulk state). Blue shift and lowering of the intensities in characteristic G and G&#39; bands of CNTs observed in Raman spectroscopy characterize the interaction between CNT surface and lipid molecules. These results suggest that the interactions between the CNTs and lipids are responsible for their mutual stabilization in aqueous solutions. As the concentrations of CNTs employed for stabilization are very low and lipid molecules are able to functionalize the CNTs, the toxicity of CNTs is expected to be insignificant while their biocompatibility is greatly enhanced. Hence the present approach finds a great potential in various biomedical applications, for instance, for developing hybrid nanocarrier systems for the delivery of multiple functional molecules as in combination therapy or polytherapy.

We report on a smart application of carbon nanotubes for kinetic stabilization of lipid particles that contain self-assembled nanostructures in their cores. The preparation of lipid particles requires rather low concentrations of carbon nanotubes permitting their use in biomedical applications such as drug delivery.

Facile Herstellung von Intern Selbstorganisierte Lipidpartikel stabilisiert durch Kohlenstoff-Nanoröhren

We present a facile method to prepare nanostructured lipid particles stabilized by carbon nanotubes (CNTs). Single-walled (pristine) and multi-walled ...

Preparation and Characterization of Lipophilic Doxorubicin Pro-drug Micelles

Micelles have been successfully used for the delivery of anticancer drugs. Amphiphilic polymers form core-shell structured micelles in an aqueous environment through self-assembly. The hydrophobic core of micelles functions as a drug reservoir and encapsulates hydrophobic drugs. The hydrophilic shell prevents the aggregation of micelles and also prolongs their systemic circulation in vivo. In this protocol, we describe a method to synthesize a doxorubicin lipophilic pro-drug, doxorubicin-palmitic acid (DOX-PA), which will enhance drug loading into micelles. A pH-sensitive hydrazone linker was used to conjugate doxorubicin with the lipid, which facilitates the release of free doxorubicin inside cancer cells. Synthesized DOX-PA was purified with a silica gel column using dichloromethane/methanol as the eluent. Purified DOX-PA was analyzed with thin layer chromatography (TLC) and 1H-Nuclear Magnetic Resonance Spectroscopy (1H-NMR). A film dispersion method was used to prepare DOX-PA loaded DSPE-PEG micelles. In addition, several methods for characterizing micelle formulations are described, including determination of DOX-PA concentration and encapsulation efficiency, measurement of particle size and distribution, and assessment of in vitro anticancer activities. This protocol provides useful information regarding the preparation and characterization of drug-loaded micelles and thus will facilitate the research and development of novel micelle-based cancer nanomedicines.

A protocol for the preparation and characterization of lipophilic doxorubicin pro-drug loaded 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG) micelles is described.

Herstellung und Charakterisierung von Lipophile Doxorubicin Pro-drug Mizellen

Micelles have been successfully used for the delivery of anticancer drugs. Amphiphilic polymers form core-shell structured micelles in an aqueous ...

Biotechnik

Phase Change Dimethyldioctadecylammonium-Shelled Microdroplets as a Promising Drug Delivery System: Results on 3D Spheroids of Mammalian Tumor Cells

Significant improvement of phase-change perfluorocarbon microdroplets (MDs) in the vast theranostic scenario passes through the optimization of the MDs composition with respect to synthesis efficiency, stability, and drug delivery capability. To this aim, decafluoropentane (DFP) MDs stabilized by a shell of dimethyldioctadecylammonium bromide (DDAB) cationic surfactant were designed. A high concentration of DDAB-MDs was readily obtained within a few seconds by pulsed high-power insonation, resulting in low polydisperse 1 &#181;m size droplets. Highly positive &#950;-potential, together with a long, saturated hydrocarbon chains of the DDAB shell, are key factors to stabilize the droplet and the drug cargo therein. The high affinity of the DDAB shell with cell plasma membrane allows for localized chemotherapeutics delivery by increasing the drug concentration at the tumor cell interface and boosting the uptake. This would turn DDAB-MDs into a relevant drug delivery tool exhibiting high antitumor activity at very low drug doses.
In this work, the efficacy of such an approach is shown to dramatically improve the effect of doxorubicin against 3D spheroids of mammalian tumor cells, MDA-MB-231. The use of&#160;three-dimensional (3D) cell cultures developed in the form of multicellular tumor spheroids (i.e., densely packed cells in a spherical shape) has numerous advantages compared to 2D cell cultures: in addition to have the potential to bridge the gap between conventional in vitro studies and animal testing, it will improve the ability to perform more predictive in vitro screening assays for preclinical drug development or evaluate the potential of off-label drugs and new co-targeting strategies.

Decafluoropentane microdroplets developed with a shell of dimethyldioctadecylammonium bromide exhibited an exceptional colloidal stability and an actractive biointerface. DDAB-MDs proved to be efficient drug reservoirs characterized by a high affinity to plasma membranes together with enhanced uptake and antitumor activity of Doxorubicin against human triple-negative breast cancer (MDA-MB-231) 3D model.

Significant improvement of phase-change perfluorocarbon microdroplets (MDs) in the vast theranostic scenario passes through the optimization of the MDs ...

Targeted Plasma Membrane Delivery of a Hydrophobic Cargo Encapsulated in a Liquid Crystal Nanoparticle Carrier

The controlled delivery of drug/imaging agents to cells is critical for the development of therapeutics and for the study of cellular signaling processes. Recently, nanoparticles (NPs) have shown significant promise in the development of such delivery systems. Here, a liquid crystal NP (LCNP)-based delivery system has been employed for the controlled delivery of a water-insoluble dye, 3,3&#8242;-dioctadecyloxacarbocyanine perchlorate (DiO), from within the NP core to the hydrophobic region of a plasma membrane bilayer. During the synthesis of the NPs, the dye was efficiently incorporated into the hydrophobic LCNP core, as confirmed by multiple spectroscopic analyses. Conjugation of a PEGylated cholesterol derivative to the NP surface (DiO-LCNP-PEG-Chol) enabled the binding of the dye-loaded NPs to the plasma membrane in HEK 293T/17 cells. Time-resolved laser scanning confocal microscopy and F&#246;rster resonance energy transfer (FRET) imaging confirmed the passive efflux of DiO from the LCNP core and its insertion into the plasma membrane bilayer. Finally, the delivery of DiO as a LCNP-PEG-Chol attenuated the cytotoxicity of DiO; the NP form of DiO exhibited ~30-40% less toxicity compared to DiOfree delivered from bulk solution. This approach demonstrates the utility of the LCNP platform as an efficient modality for the membrane-specific delivery and modulation of hydrophobic molecular cargos.

A liquid crystal nanoparticle (LCNP) nanocarrier is exploited as a vehicle for the controlled delivery of a hydrophobic cargo to the plasma membrane of living cells.

Gezielte Plasma Membrane Lieferung eines Hydrophobic Transport Encapsulated in einem Liquid Crystal Nanoparticle Träger

The controlled delivery of drug/imaging agents to cells is critical for the development of therapeutics and for the study of cellular signaling processes. ...

Formulation and Characterization of Bioactive Agent Containing Nanodisks

The term nanodisk refers to a discrete type of nanoparticle comprised of a bilayer forming lipid, a scaffold protein, and an integrated bioactive agent. Nanodisks are organized as a disk-shaped lipid bilayer whose perimeter is circumscribed by the scaffold protein, usually a member of the exchangeable apolipoprotein family. Numerous hydrophobic bioactive agents have been efficiently solubilized in nanodisks by their integration into the hydrophobic milieu of the particle&#39;s lipid bilayer, yielding a largely homogenous population of particles in the range of 10-20 nm in diameter. The formulation of nanodisks requires a precise ratio of individual components, an appropriate sequential addition of each component, followed by bath sonication of the formulation mixture. The amphipathic scaffold protein spontaneously contacts and reorganizes the dispersed bilayer forming lipid/bioactive agent mixture to form a discrete, homogeneous population of nanodisk&#160;particles. During this process, the reaction mixture transitions from an opaque, turbid appearance to a clarified sample that, when fully optimized, yields no precipitate upon centrifugation. Characterization studies involve the determination of bioactive agent solubilization efficiency, electron microscopy, gel filtration chromatography, ultraviolet visible (UV/Vis) absorbance spectroscopy, and/or fluorescence spectroscopy. This is normally followed by an investigation of biological activity using cultured cells or mice. In the case of nanodisks harboring an antibiotic (i.e., the macrolide polyene antibiotic amphotericin B), their ability to inhibit the growth of yeast or fungi as a function of concentration or time can be measured. The relative ease of formulation, versatility with respect to component parts, nanoscale particle size, inherent stability, and aqueous solubility permits myriad in vitro and in vivo applications of nanodisk technology. In the present article, we describe a general methodology to formulate and characterize nanodisks containing amphotericin&#160;B as the hydrophobic bioactive agent.

Here, we describe the production and characterization of bioactive agents containing nanodisks. Amphotericin B nanodisks are taken as an example to describe the protocol in a stepwise manner.

Formulierung und Charakterisierung bioaktiver Wirkstoffe, die Nanoscheiben enthalten

The term nanodisk refers to a discrete type of nanoparticle comprised of a bilayer forming lipid, a scaffold protein, and an integrated bioactive agent. ...

Uptake of New Lipid-coated Nanoparticles Containing Falcarindiol by Human Mesenchymal Stem Cells

Nanoparticles are the focus of an increased interest in drug delivery systems for cancer therapy. Lipid-coated nanoparticles are inspired in structure and size by low-density lipoproteins (LDLs) because cancer cells have an increased need for cholesterol to proliferate, and this has been exploited as a mechanism for delivering anticancer drugs to cancer cells. Moreover, depending on drug chemistry, encapsulating the drug can be advantageous to avoid degradation of the drug during circulation in vivo. Therefore, in this&#160;study, this design is used to fabricate lipid-coated nanoparticles of the anticancer drug falcarindiol, providing a potential new delivery system of falcarindiol in order to stabilize its chemical structure against degradation and improve its uptake by tumors. Falcarindiol nanoparticles, with a phospholipid and cholesterol monolayer encapsulating the purified drug core of the particle, were designed. The lipid monolayer coating consists of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol (Chol), and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE PEG 2000) along with the fluorescent label DiI (molar ratios of 43:50:5:2). The nanoparticles are fabricated using the rapid injection method, which is a fast and simple technique to precipitate nanoparticles by good-solvent for anti-solvent exchange. It consists of a rapid injection of an ethanol solution containing the nanoparticle components into an aqueous phase. The size of the fluorescent nanoparticles is measured using dynamic light scattering (DLS) at 74.1 &#177; 6.7 nm. The uptake of the nanoparticles is tested in human mesenchymal stem cells (hMSCs) and imaged using fluorescence and confocal microscopy. The uptake of the nanoparticles is observed in hMSCs, suggesting the potential for such a stable drug delivery system for falcarindiol.

This article describes the encapsulation of falcarindiol in lipid-coated 74 nm nanoparticles. The cellular uptake of the nanoparticles&#160;by human stem cells into lipid droplets is monitored by fluorescent and confocal imaging. Nanoparticles are fabricated by the rapid injection method of solvent shifting, and their size is measured with the dynamic light scattering technique.

Aufnahme von neuen Lipid-beschichteten Nanopartikeln mit Falcarindiol von humanen mesenchymalen Stammzellen

Nanoparticles are the focus of an increased interest in drug delivery systems for cancer therapy. Lipid-coated nanoparticles are inspired in structure and ...

Preparation and Characterization of Nanoliposomes for the Entrapment of Bioactive Hydrophilic Globular Proteins

Liposome nanocapsules have been applied for many purposes in the pharmaceutical, cosmetic, and food industries. Attributes of liposomes include their biocompatibility, biodegradability, non-immunogenicity, non-toxicity, and ability to entrap both hydrophilic and hydrophobic compounds. The classical hydration of thin lipid films in an organic solvent is applied herein as a technique to encapsulate tarin, a plant lectin, in nanoliposomes. Nanoliposome size, stability, entrapment efficiency, and morphological characterization are described in detail. The nanoliposomes are prepared using 1,2-dioleoyl-sn-glycerol-3-phosphoethanolamine (DOPE), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (ammonium salt; DSPE-MPEG 2000), and cholesterylhemisuccinate (CHEMS) as the main constituents. Lipids are first dissolved in chloroform to obtain a thin lipid film that is subsequently rehydrated in ammonium sulfate solution containing the protein to be entrapped and incubated overnight. Then, sonication and extrusion techniques are applied to generate nanosized unilamellar vesicles. The size and polydispersity index of the nanovesicles are determined by dynamic light scattering, while nanovesicle morphology is assessed by scanning electron microscopy. Entrapment efficiency is determined by the ratio of the amount of unencapsulated protein to original amount of initially loaded protein. Homogeneous liposomes are obtained with an average size of 155 nm and polydispersity index value of 0.168. A high entrapment efficiency of 83% is achieved.

This study describes classical hydration using the thin lipid film method for nanoliposome preparation followed by nanoparticle characterization. A 47 kDa-hydrophilic and globular protein, tarin, is successfully encapsulated as a strategy to improve stability, avoid fast clearance, and promote controlled release. The method can be adapted to hydrophobic molecules encapsulation.

Vorbereitung und Charakterisierung von Nanoliposomen zur Entrapment ierung bioaktiver hydrophiler Globularproteine

Liposome nanocapsules have been applied for many purposes in the pharmaceutical, cosmetic, and food industries. Attributes of liposomes include their ...

Using In Vitro Live-cell Imaging to Explore Chemotherapeutics Delivered by Lipid-based Nanoparticles

Conventional imaging techniques can provide detailed information about cellular processes. However, this information is based on static images in an otherwise dynamic system, and successive phases are easily overlooked or misinterpreted. Live-cell imaging and time-lapse microscopy, in which living cells can be followed for hours or even days in a more or less continuous fashion, are therefore very informative. The protocol described here allows for the investigation of the fate of chemotherapeutic nanoparticles after the delivery of doxorubicin (dox) in living cells. Dox is an intercalating agent that must be released from its nanocarrier to become biologically active. In spite of its clinical registration for more than two decades, its uptake, breakdown, and drug release are still not fully understood. This article explores the hypothesis that lipid-based nanoparticles are taken up by the tumor cells and are slowly degraded. Released dox is then translocated to the nucleus. To prevent fixation artifacts, live-cell imaging and time-lapse microscopy, described in this experimental procedure, can be applied.

Using In Vitro Live-cell Imaging to Explore Chemotherapeutics Delivered by Lipid-based Nanoparticles

Live-cell imaging is a powerful tool to visualize dynamic processes. The examination of fixed cells provides only static pictures, which can lead to misinterpretation and confusion about the process. This work presents a method to study uptake, drug release, and intracellular localization of liposomal nanoparticles in living cells.

Verwendung von In-vitro- Live Cell Imaging zur Erkundung Chemotherapeutika geliefert durch Lipid-basierte Nanopartikel

Conventional imaging techniques can provide detailed information about cellular processes. However, this information is based on static images in an ...