Search results for "nanocapsules"

Influence of Surface Charge and Polymer Coating on Internalization and Biodistribution of Polyethylene Glycol-Modified Iron Oxide Nanoparticles

2015

International audience; The aim of this study was to investigate the influence of the surface charge and coating of Superparamagnetic Iron Oxide Nanoparticles (SPIONs) on their in vitro and in vivo behaviors. Neutral and negatively-charged PEG-based SPIONs were synthesized and compared to Resovist (R), a carboxydextran-based SPION currently used in clinics. Their cytotoxicity, cell internalization, and potential as contrast agents for magnetic resonance imaging were assessed. Neutral pegylated SPIONs were internalized less readily by the reticuloendothelial system and showed a lower uptake by the liver, compared to negatively-charged SPIONs (with carboxydextran and PEG). These results sugge…

Highly Loaded Semipermeable Nanocapsules for Magnetic Resonance Imaging.

2017

Magnetic resonance imaging has become an essential tool in medicine for the investigation of physiological processes. The key issues related to contrast agents, i.e., substances that are injected in the body for imaging, are the efficient enhancement of contrast, their low toxicity, and their defined biodistribution. Polyurea nanocapsules containing the gadolinium complex Gadobutrol as a contrast agent in high local concentration and high relaxivity up to 40 s-1 mmol-1 L are described. A high concentration of the contrast agent inside the nanocapsules can be ensured by increasing the crystallinity in the shell of the nanocapsules. Nanocapsules from aliphatic polyurea are found to display hi…

NOVEL COMPOSED GALACTOSYLATED NANODEVICES CONTAINING A RIBAVIRIN PRODRUG AS HEPATIC CELL-TARGETED CARRIERS FOR HCV TREATMENT

2013

In this paper, we describe the preparation of liver-targeted nanoparticles potentially able to carry to hepatocytes a ribavirin (RBV) prodrug, exploiting the presence of carbohydrate receptors in the liver (i.e., ASGPR in hepatocytes). These particles were obtained starting from a galactosylated phospholipid-polyaminoacid conjugate. This latter was obtained by chemical reaction of ALPHA, BETA -poly(N-2-hydroxyethyl) (2-aminoethylcarbamate)-DL-aspartamide (PHEA-EDA) with 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-(succinyl) sodium salt (DPPE), and subsequent reaction with lactose, obtaining PHEA-EDA-DPPE-GAL copolymer. To enhance the entrapment into obtained nanostructures, a hydroph…

Delivering all in one: Antigen-nanocapsule loaded with dual adjuvant yields superadditive effects by DC-directed T cell stimulation

2018

Therapeutic vaccination is and remains a major challenge, particularly in cancer treatment. In this process, the effective activation of dendritic cells by a combination of distinctly acting adjuvants and an antigen is crucial for success. While most common vaccine formulations lack the efficiency to trigger sufficient T cell responses in a therapeutic tumor treatment, nanovaccines offer unique properties to tackle that challenge. Here, we report the stepwise development of a nanocapsule for vaccination approaches, comprising a shell consisting of antigen and loaded with a superadditive adjuvant combination. In a first initial step, we identified the combination of resiquimod (R848) and mur…

Multivalency Beats Complexity: A Study on the Cell Uptake of Carbohydrate Functionalized Nanocarriers to Dendritic Cells.

2020

Herein, we report the synthesis of carbohydrate and glycodendron structures for dendritic cell targeting, which were subsequently bound to hydroxyethyl starch (HES) nanocapsules prepared by the inverse miniemulsion technique. The uptake of the carbohydrate-functionalized HES nanocapsules into immature human dendritic cells (hDCs) revealed a strong dependence on the used carbohydrate. A multivalent mannose-terminated dendron was found to be far superior in uptake compared to the structurally more complex oligosaccharides used.

Protein Corona Mediated Stealth Properties of Biocompatible Carbohydrate‐based Nanocarriers

2018

From In Silico to Experimental Validation: Tailoring Peptide Substrates for a Serine Protease.

2020

Smart nanocarriers for the transport of drugs to tumor cells are nowadays of great interest for treating cancer. The use of enzymatic stimuli to cleave peptide-based drug nanocapsules for the selective release of nanocapsule cargo in close proximity to tumor cells opens new possibilities in cancer research. In the present work, we demonstrate a methodology for finding and optimizing cleavable substrate sequences by the type II transmembrane serine protease hepsin, which is highly overexpressed in prostate cancer. The design and screening of combinatorial libraries in silico against the binding cavity of hepsin allow the identification of a panel of promising substrates with high-calculated …

Nanocarriers for optimizing the balance between interfollicular permeation and follicular uptake of topically applied clobetasol to minimize adverse …

2015

The treatment of various hair disorders has become a central focus of good dermatologic patient care as it affects men and women all over the world. For many inflammatory-based scalp diseases, glucocorticoids are an essential part of treatment, even though they are known to cause systemic as well as local adverse effects when applied topically. Therefore, efficient targeting and avoidance of these side effects are of utmost importance. Optimizing the balance between drug release, interfollicular permeation, and follicular uptake may allow minimizing these adverse events and simultaneously improve drug delivery, given that one succeeds in targeting a sustained release formulation to the hair…

Dual Enzyme-Responsive Capsules of Hyaluronic Acid-block-Poly(Lactic Acid) for Sensing Bacterial Enzymes.

2015

The synthesis of novel amphiphilic hyaluronic acid (HYA) and poly(lactic acid) (PLA) block copolymers is reported as the key element of a strategy to detect the presence of pathogenic bacterial enzymes. In addition to the formation of defined HYA-block-PLA assemblies, the encapsulation of fluorescent reporter dyes and the selective enzymatic degradation of the capsules by hyaluronidase and proteinase K are studied. The synthesis of the dual enzyme-responsive HYA-b-PLA is carried out by copper-catalyzed Huisgen 1,3-dipolar cycloaddition. The resulting copolymers are assembled in water to form vesicular structures, which are characterized by scanning electron microscopy, transmission electron…

Ceria/polymer nanocontainers for high-performance encapsulation of fluorophores

2019

We report the synthesis of high-performance organic–inorganic hybrid fluorescent nanocapsules comprising a polymer shell armored with an inorganic layer and a liquid core containing a fluorophore. The polymeric capsules are synthesized by free radical miniemulsion polymerization and contain covalently bound carboxylate surface functionalities that allow for the binding of metal ions through electrostatic interaction. A cerium(IV) oxide nanoparticle layer, formed in situ at the surface of the hybrid nanocapsules, acts as oxygen scavenger and keeps external reactive molecular oxygen from entering into the capsules, eventually resulting in a reduction of the photooxidation of encapsulated fluo…