Search results for "nanoparticle"

Biotin-Containing Reduced Graphene Oxide-Based Nanosystem as a Multieffect Anticancer Agent: Combining Hyperthermia with Targeted Chemotherapy

2015

Among the relevant properties of graphene derivatives, their ability of acting as an energy-converting device so as to produce heat (i.e., thermoablation and hyperthermia) was more recently taken into account for the treatment of solid tumors. In this pioneering study, for the first time, the in vitro RGO-induced hyperthermia was assessed and combined with the stimuli-sensitive anticancer effect of a biotinylated inulin-doxorubicin conjugate (CJ-PEGBT), hence, getting to a nanosystem endowed with synergic anticancer effects and high specificity. CJ-PEGBT was synthesized by linking pentynoic acid and citraconic acid to inulin. The citraconylamide pendants, used as pH reversible spacer, were …

Amphiphilic Copolymers Based on Poly[(hydroxyethyl)-d,l-aspartamide]: A Suitable Functional Coating for Biocompatible Gold Nanostars

2013

Novel amphiphilic copolymers have been synthesized based on a biocompatible poly(hydroxyethylaspartamide) (PHEA) backbone, bearing both anchoring groups for gold nanoparticles, such as thiols and disulfide, and conjugable moieties, such as amino groups, the latter as points suitable for appending further functional agents. The strategy was to functionalize α,β-poly[(N-2- hydroxyethyl)-d,l-aspartamide] (PHEA) with PEG2000-NH2 and with ethylenediamine (EDA) obtaining a partially pegylated copolymer with a large number of pendant primary amino groups. A fraction of the latter was conjugated with molecules bearing terminal thiol moieties such as 12-mercaptododecanoic acid (MDA) and disulfide gr…

Size- and coating-dependent uptake of polymer-coated gold nanoparticles in primary human dermal microvascular endothelial cells.

2012

A library-orientated approach is used to gain understanding of the interactions of well-defined nanoparticles with primary human endothelial cells, which are a key component of the vasculature. Fifteen sequentially modified gold nanoparticles (AuNPs) based on three different core sizes (18, 35, 65 nm) and five polymeric coatings were prepared. The synthetic methodology ensured homogeneity across each series of particles to allow sequential investigation of the chemical features on cellular interactions. The toxicity of these nanoparticles, their uptake behavior in primary human dermal microvascular endothelial cells (HDMECs), and quantification of uptake were all investigated. The results o…

α-Mannosyl-Functionalized Cationic Nanohydrogel Particles for Targeted Gene Knockdown in Immunosuppressive Macrophages

2019

Immunosuppressive M2 macrophages govern the immunophathogenic micromilieu in many severe diseases including cancer or fibrosis, thus, their re-polarization through RNA interference is a promising concept to support combinatorial therapies. For targeted siRNA delivery, however, safe and stable carriers are required that manage cell specific transport to M2 macrophages. Here, siRNA-loaded cationic nanogels are reported with α-mannosyl decorated surfaces that target and modify M2 macrophages selectively. Via amphiphilic precursor block copolymers bearing one single α-mannosyl moiety at their chain end mannosylated cationic nanohydrogel particles (ManNP) were obtained of 20 nm diameter determin…

Effect of Core-Crosslinking on Protein Corona Formation on Polymeric Micelles.

2021

Most nanomaterials acquire a protein corona upon contact with biological fluids. The magnitude of this effect is strongly dependent both on surface and structure of the nanoparticle. To define the contribution of the internal nanoparticle structure, protein corona formation of block copolymer micelles with poly(N-2-hydroxypropylmethacrylamide) (pHPMA) as hydrophilic shell, which are crosslinked-or not-in the hydrophobic core is comparatively analyzed. Both types of micelles are incubated with human blood plasma and separated by asymmetrical flow field-flow fractionation (AF4). Their size is determined by dynamic light scattering and proteins within the micellar fraction are characterized by…

From Polymers to Functional Biomaterials.

2017

Studies on the structure of coumarin-modified dextran nanoparticles by fluorescence spectroscopy.

2012

The photophysical and photochemical characteristics of nano-scaled particles obtained via solvent displacement from coumarin-modified dextrans were studied by means of absorption- and fluorescence-spectroscopy. The environment-dependent fluorescence emission of the pendant 4-methyl-7-alkoxy coumarin groups was exploited as a probe to gain information about the inner structure of the polysaccharide based nanoparticles. Time-resolved fluorescence measurements showed that the particles had two domains of different polarity and it could be confirmed that the core of the nano-assemblies contained water. Moreover, preliminary experiments were carried out demonstrating the possibility to control t…

Combining inulin multifunctional polycation and magnetic nanoparticles: Redox-responsive siRNA-loaded systems for magnetofection

2019

Superparamagnetic Iron Oxide Nanoparticles (SPIONs) are recognized as one of the most promising agents for theranostic applications. Among methods designed for siRNA delivery, magnetofection, that is, nucleic acid cell uptake under the influence of a magnetic field acting on magnetic nucleic acid vectors, is emerging as a unique approach to combining advantages such as strong improvement of the kinetics of the delivery process and the possibility of localizing nucleic acid delivery to an area where the magnetic field is applied. This paper reports on the preparation of siRNA loaded magnetoplexes&mdash

An assembly of organic-inorganic composites using halloysite clay nanotubes

2018

Halloysite is natural tubular clay suitable as a component of biocompatible nanosystems with specific functionalities. The selective modification of halloysite inner/outer surfaces can be achieved by exploiting supramolecular and covalent interactions resulting in controlled colloidal stability adjusted to the solvent polarity. The functionalized halloysite nanotubes can be employed as reinforcing filler for polymers as well as carriers for the sustained release of active molecules, such as antioxidants, flame-retardants, corrosion inhibitors, biocides and drugs. The tubular morphology makes halloysite a perspective template for core-shell metal supports for mesoporous catalysts. The cataly…

Enhanced in vivo targeting of murine nonparenchymal liver cells with monophosphoryl lipid A functionalized microcapsules.

2014

A broad spectrum of infectious liver diseases emphasizes the need of microparticles for targeted delivery of immunomodulatory substances to the liver. Microcapsules (MCs) are particularly attractive for innovative drug and vaccine formulations, enabling the combination of antigen, drugs, and adjuvants. The present study aimed to develop microcapsules characterized by an enhanced liver deposition and accelerated uptake by nonparenchymal liver cells (NPCs). Initially, two formulations of biodegradable microcapsules were synthesized from either hydroxyethyl starch (HES) or mannose. Notably, HES-MCs accumulated primarily in the liver, while mannose particles displayed a lung preference. Functio…