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1.
Colloids Surf B Biointerfaces ; 141: 148-157, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26852098

RESUMEN

In the last decades, nano-oncologicals bearing a polyethylene glycol (PEG) coating are being emerging as biomimetic devices able to drive their drug cargo to solid tumors through passive mechanisms. To improve selectivity toward cancer cells, nanocarriers decorated with the small ligand folate have been widely investigated. Nevertheless, a great challenge remains the effective exposition of folate on nanoparticles (NPs), which is a key prerequisite to ensure the correct binding to receptor and the following endocytic uptake. On these premises, in this study we propose a novel strategy to produce core-shell folate-targeted NPs based on diblock copolymers of poly(ε-caprolactone) (PCL) and PEG through the aid of (2-hydroxypropyl)-ß-cyclodextrin (HPßCD). PCL4300-PEG2000 and PCL4300-PEG2000-Fol copolymers were synthesized, characterized and employed to produce NPs without and with HPßCD by a melting/sonication procedure. Colloidal properties of targeted NPs produced with HPßCD demonstrated a highly extended conformation of PEG chains in the shell, an enhanced interaction with a specific antibody against folate and a higher uptake in cells overexpressing folate receptor. Overall, these results suggest that proper manipulation of PEG shell conformation through HPßCD can represent a novel non-covalent strategy to modify shell features.


Asunto(s)
Ácido Fólico/química , Nanopartículas/química , Poliésteres/química , Polietilenglicoles/química , beta-Ciclodextrinas/química , Células A549 , Calorimetría/métodos , Caproatos/química , Línea Celular Tumoral , Portadores de Fármacos/química , Endocitosis , Receptores de Folato Anclados a GPI/metabolismo , Ácido Fólico/metabolismo , Ácido Fólico/farmacocinética , Humanos , Lactonas/química , Tamaño de la Partícula , Espectroscopía de Protones por Resonancia Magnética
2.
J Colloid Interface Sci ; 454: 112-20, 2015 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26004575

RESUMEN

The aim of this work was to investigate the potential of small nanoparticles (NPs) made of a poly(ethylene glycol)-poly(ε-caprolactone)-amphiphilic diblock copolymer (PEG-b-PCL, PEG=2kDa and PCL=4.2kDa) as drug carrier system through the skin. Zinc(II) phthalocyanine (ZnPc), selected as lipophilic and fluorescent model molecule, was loaded inside NPs by a melting/sonication procedure. Loaded NPs with a hydrodynamic diameter around 60nm, a slightly negative zeta potential and a ZnPc entrapment dependent on polymer/ZnPc ratio were obtained. Spectroscopic investigations evidenced that ZnPc was entrapped in monomeric form maintaining its emission properties. The transport of ZnPc through porcine ear skin was evaluated on Franz-type diffusion cells after treatment with different vehicles (water or PEG 0.4kDa) containing free ZnPc or ZnPc-loaded NPs without and with (2-hydroxypropyl)-ß-cyclodextrin (HPßCD) as permeation enhancer. Independently of the sample tested, ZnPc was transported in the skin without reaching receptor compartment. On the other hand, ZnPc was found in the skin in large amount and also in the viable epidermis when delivered through NPs associated with HPßCD, especially in conditions limiting water evaporation. Fluorescence images of skin samples after 24h of permeation were in line with ZnPc dosage in the skin and demonstrated the ability of NPs covalently tagged with rhodamine to penetrate the skin and to locate in the intercellular spaces. Insight into skin chemical properties upon application of NPs by confocal Raman spectroscopy demonstrated that HPßCD caused an alteration of water profile in the skin, highly reducing the degree of hydration at stratum corneum/viable epidermis interface which can promote NP transport. Taken together, these results highlight PEG-b-PCL NPs coupled with HPßCD as a novel vehicle for the skin delivery of highly lipophilic compounds paving the way to several applications.


Asunto(s)
Portadores de Fármacos , Lactonas/química , Nanopartículas/química , Polietilenglicoles/química , Piel/efectos de los fármacos , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Animales , Transporte Biológico , Composición de Medicamentos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/metabolismo , Indoles/química , Indoles/metabolismo , Isoindoles , Lactonas/farmacología , Nanopartículas/metabolismo , Nanopartículas/ultraestructura , Compuestos Organometálicos/química , Compuestos Organometálicos/metabolismo , Tamaño de la Partícula , Permeabilidad/efectos de los fármacos , Polietilenglicoles/farmacología , Piel/metabolismo , Sonicación , Electricidad Estática , Porcinos , Técnicas de Cultivo de Tejidos , Agua/química , Agua/metabolismo , Compuestos de Zinc , beta-Ciclodextrinas/farmacología
3.
Nanoscale ; 7(13): 5643-53, 2015 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-25648974

RESUMEN

In the attempt to develop novel concepts in designing targeted nanoparticles for combination therapy of cancer, we propose here CD44-targeted hyaluronan-decorated double-coated nanoparticles (dcNPs) delivering the lipophilic chemotherapeutic docetaxel (DTX) and an anionic porphyrin (TPPS4). dcNPs are based on electrostatic interactions between a negative DTX-loaded nanoscaffold of poly(lactide-co-glycolide), a polycationic shell of polyethyleneimine entangling negatively-charged TPPS4 and finally decorated with hyaluronan (HA) to promote internalization through CD44 receptor-mediated endocytosis. DTX/TPPS4-dcNPs, prepared through layer-by-layer deposition, showed a hydrodynamic diameter of around 180 nm, negative zeta potential and efficient loading of both DTX and TPPS4. DTX/TPPS4-dcNPs were freeze-dried with trehalose giving a powder that could be easily dispersed in different media. Excellent stability of dcNPs in specific salt- and protein-containing media was found. Spectroscopic behavior of DTX/TPPS4-dcNPs demonstrated a face-to-face arrangement of the TPPS4 units in non-photoresponsive H-type aggregates accounting for an extensive aggregation of the porphyrin embedded in the shell. Experiments in MDA-MB-231 cells overexpressing the CD44 receptor demonstrated a 9.4-fold increase in the intracellular level of TPPS4 delivered from dcNPs as compared to free TPPS4. Light-induced death increased tremendously in cells that had been treated with a combination of TPPS4 and DTX delivered through dcNPs as compared with free drugs, presumably due to efficient uptake and co-localization inside the cells. In perspective, the strategy proposed here to target synergistic drug combinations through HA-decorated nanoparticles seems very attractive to improve the specificity and efficacy of cancer treatment.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/administración & dosificación , Receptores de Hialuranos/metabolismo , Ácido Hialurónico/farmacocinética , Fotoquimioterapia/métodos , Porfirinas/administración & dosificación , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/administración & dosificación , Materiales Biocompatibles Revestidos/síntesis química , Terapia Combinada/métodos , Difusión , Humanos , Ácido Hialurónico/química , Células MCF-7 , Nanocápsulas/administración & dosificación , Nanocápsulas/química , Nanocápsulas/ultraestructura , Fármacos Fotosensibilizantes/administración & dosificación , Polímeros/química , Resultado del Tratamiento
4.
Carbohydr Polym ; 112: 736-45, 2014 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-25129803

RESUMEN

In this work, a well-defined hydrogel was developed by coupling chitosan with PEO through "click chemistry". Azide functionalities were introduced onto chitosan, through mesylation of C-6 hydroxyl groups, and reacted with a di-alkyne PEO by a regioselective Cu(I)-catalyzed cycloaddition. This synthetic approach allowed us to obtain a hydrogel with a controlled crosslinking degree. In fact, the extent of coupling is strictly dependent on the amount of azido groups on chitosan, which in turn can be easily modulated. The obtained hydrogel, with a crosslinking degree of around 90%, showed interesting swelling properties. With respect to chitosan hydrogels reported in literature, a considerably higher equilibrium uptake was reached (940%). The possibility to control the crosslinking degree of hydrogel and its capability to rapidly absorb high amounts of water make this material suitable for several applications, such as controlled drug release and wound healing.


Asunto(s)
Quitosano/química , Hidrogeles/química , Polietilenglicoles/química , Quitosano/síntesis química , Química Clic/métodos , Reacción de Cicloadición
5.
Int J Pharm ; 473(1-2): 55-63, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24992317

RESUMEN

With the aim to find novel therapeutical approaches for triple-negative breast cancer (TNBC) treatment, we have developed a powder for i.v. injection based on cyclodextrins and docetaxel (DTX)-loaded polyethyleneglycol-poly(epsilon-caprolactone) nanoparticles (DTX-NPs). Nanoparticles are designed to concentrate at tumor level by enhanced permeability and retention effect and release drug cargo at a sustained rate in the blood and in tumor interstitium. DTX-NPs of around 70 nm, shielding proteins and allowing a sustained DTX release for about 30 days, were produced by melting sonication technique. DTX-NPs were associated to hydroxypropyl-ß-cyclodextrin to give a powder for injection with excellent dispersibility and suitable for i.v. administration. DTX-NPs were as efficient as free DTX in inhibiting cell growth of MDA-MB231 cells, even at low concentrations, and displayed a comparable in vivo antitumor efficacy and better survival in a TNBC animal model as compared with DTX commercial formulation (Taxotere(®)). In conclusion, PEGylated biodegradable DTX-NPs highlighted their potential in the treatment of aggressive TNBC providing a foundation for future clinical studies.


Asunto(s)
Antineoplásicos/administración & dosificación , Glicoles de Etileno/química , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Nanopartículas/administración & dosificación , Poliésteres/química , Taxoides/administración & dosificación , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , 2-Hidroxipropil-beta-Ciclodextrina , Animales , Antineoplásicos/química , Proteínas Sanguíneas/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/química , Docetaxel , Femenino , Humanos , Neoplasias Mamarias Experimentales/patología , Ratones Desnudos , Nanopartículas/química , Polvos , Taxoides/química , Neoplasias de la Mama Triple Negativas/patología , Carga Tumoral/efectos de los fármacos , beta-Ciclodextrinas/química
6.
Biomacromolecules ; 12(12): 4221-9, 2011 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-22047492

RESUMEN

Well-defined amphiphilic Y-shaped miktoarm star-block copolymers of PEO and PCL were synthesized by ring-opening polymerization of ε-caprolactone initiated by a PEO-bound lysine macroinitiator. The copolymers were characterized by (1)H NMR, SEC, DSC, and WAXD techniques. Separate PCL and PEO crystalline phases occur in melt-crystallized copolymers when their segmental lengths were comparable and the PCL content was ≤80 wt %. Self-assembling of these copolymers in aqueous medium led to nanoaggregates with low critical aggregation concentration values (0.35 to 1.6 mg·L(-1)) and size depending on composition. Despite the fact that copolymers were not prone to self-organize in vesicles, once processed by a novel w/o emulsion-melting-sonication technique, they gave nanocapsules with a water core and a hydrophilic surface. A macromolecular fluorescent dye was effectively loaded and released at sustained rate by optimizing nanocapsule formulation. The results demonstrate that amphiphilic block copolymers can be assembled in different kinds of nanomorphologies independently of their hydrophilic/hydrophobic balance and architecture through specifically designed preparation techniques.


Asunto(s)
Materiales Biocompatibles/síntesis química , Sistemas de Liberación de Medicamentos/métodos , Nanocápsulas , Poliésteres/síntesis química , Caproatos/metabolismo , Interacciones Hidrofóbicas e Hidrofílicas , Lactonas/metabolismo , Lisina/metabolismo , Polímeros/química
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