Search results for "Delivery"
showing 10 items of 1271 documents
Polymeric nanoparticles of different sizes overcome the cell membrane barrier.
2012
Abstract Polymeric nanoparticles have tremendous potential either as carriers or markers in treatment for diseases or as diagnostics in biomedical applications. Finding the optimal conditions for effective intracellular delivery of the payload to the location of interest is still a big challenge. The particles have to overcome the barrier of the cell membrane. Here, we investigated the uptake in HeLa cells of fluorescent polystyrene particles with different size and surface charge. Particles stabilized with the nonionic surfactant Lutensol AT50® (132 nm, 180 nm, 242 nm, 816 nm, 846 nm diameter) were synthesized via dispersion polymerization. Cationic particles (120 nm, 208 nm, 267 nm, 603 n…
Molecular insights and novel approaches for targeting tumor metastasis
2020
In recent years, due to the effective drug delivery and preciseness of tumor sites or microenvironment, the targeted drug delivery approaches have gained ample attention for tumor metastasis therapy. The conventional treatment approaches for metastasis therapy have reported with immense adverse effects because they exhibited maximum probability of killing the carcinogenic cells along with healthy cells. The tumor vasculature, comprising of vasculogenic impressions and angiogenesis, greatly depends upon the growth and metastasis in the tumors. Therefore, various nanocarriers-based delivery approaches for targeting to tumor vasculature have been attempted as efficient and potential approaches…
Mucoadhesive polymers for oral transmucosal drug delivery: a review.
2012
The oral mucosa offers an interesting site for the application of dosage forms that release drugs within/throughout the oral mucosa, by assuring a high drug bioavailability for topic and systemic effects. However, the relative permeability of the oral mucosa and the washing effect related to the oral fluids and mechanical stresses must be considered in the formulation of oral dosage forms. Since a sustained drug release can be guaranteed only if dosage forms remain in contact with the oral site of absorption/application for a prolonged time, the development of mucoadhesive dosage forms is mandatory. The mucoadhesion is a complex phenomenon and the mucoadhesive bond consists of two different…
Uptake of polymeric nanoparticles in a human induced pluripotent stem cell-based blood-brain barrier model: Impact of size, material, and protein cor…
2021
The blood–brain barrier (BBB) maintains the homeostasis of the central nervous system, which is one of the reasons for the treatments of brain disorders being challenging in nature. Nanoparticles (NPs) have been seen as potential drug delivery systems to the brain overcoming the tight barrier of endothelial cells. Using a BBB model system based on human induced pluripotent stem cells (iPSCs), the impact of polymeric nanoparticles has been studied in relation to nanoparticle size, material, and protein corona. PLGA [poly(lactic-co-glycolic acid)] and PLLA [poly(d,l-lactide)] nanoparticles stabilized with Tween® 80 were synthesized (50 and 100 nm). iPSCs were differentiated into human brain m…
Poly(lactic acid)/carvacrol-based materials: preparation, physicochemical properties, and antimicrobial activity
2020
The current demand for new antimicrobial systems has stimulated research for the development of poly(lactic acid)/carvacrol (PLA/CAR)-based materials able to hinder the growth and spread of microorganisms. The eco-friendly characteristics of PLA and cytocompatibility make it very promising in the perspective of green chemistry applications as material for food and biomedical employments. The broad-spectrum biological and pharmacological properties of CAR, including antimicrobial activity, make it an interesting bioactive molecule that can be easily compounded with PLA by adopting the same techniques as those commonly used for PLA manufacturing. This review critically discusses the most comm…
NO2-controlled cargo delivery from gated silica mesoporous nanoparticles
2017
[EN] Cargo delivery from mesoporous silica nanoparticles loaded with sulforhodamine B and capped with a difluoroboron-dipyrromethene (BODIPY) derivative was triggered by a NO2-induced oxidative process.
Pentafluorophenyl Ester-based Polymersomes as Nanosized Drug-Delivery Vehicles
2015
In this work, activated ester chemistry is employed to synthesize biocompatible and readily functionalizable polymersomes. Via aminolysis of pentafluorophenyl methacrylate-based precursor polymers, an N-(2-hydroxypropyl) methacrylamide (HPMA)-analog hydrophilic block is obtained. The precursor polymers can be versatile functionalized by simple addition of suitable primary amines during aminolysis as demonstrated using a fluorescent dye. Vesicle formation is proven by cryoTEM and light scattering. High encapsulation efficiencies for hydrophilic cargo like siRNA are achieved using dual centrifugation and safe encapsulation is demonstrated by gel electrophoresis. In vitro studies reveal low cy…
Galactosylated polyaspartamide copolymers for siRNA targeted delivery to hepatocellular carcinoma cells
2017
The limited efficacy of available treatments for hepatocellular carcinoma (HCC) requires the development of novel therapeutic approaches. We synthesized a novel cationic polymer based on α,β-poly-(N-2-hydroxyethyl)-D,L-aspartamide (PHEA) for drug delivery to HCC cells. The copolymer was synthesized by subsequent derivatization of PHEA with diethylene triamine (DETA) and with a polyethylene glycol (PEG) derivative bearing galactose (GAL) molecules, obtaining the cationic derivative PHEA-DETA-PEG-GAL. PHEA-DETA-PEG-GAL has suitable chemical-physical characteristics for a potential systemic use and can effectively deliver a siRNA (siE2F1) targeted against the transcription factor E2F1, a gen…
Polysorbate-80 coating enhances uptake of polybutylcyanoacrylate (PBCA)-nanoparticles by human and bovine primary brain capillary endothelial cells
2000
Certain drugs such as dalargin, loperamide or tubocurarine are not transported across the blood-brain barrier (BBB) and therefore exhibit no effects on the central nervous system. However, effects on the central nervous system can be observed when these drugs are loaded onto polybutylcyanoacrylate (PBCA)-nanoparticles and coated with polysorbate 80. The mechanism by which these complexed nanoparticles cross the BBB and exhibit their effects has not been elucidated. Cultured microvessel brain endothelial cells of human and bovine origin were used as an in vitro model for the BBB to gain further insight into the mechanism of uptake of nanoparticles. With cells from these species we were able …
Synthesis and characterization of redox-sensitive polyurethanes based on L-glutathione oxidized and poly(ether ester) triblock copolymers
2021
Abstract Segmented polyurethanes, based on PCL-PEG-PCL copolymers, 1,4-diisocyanatobutane and l -glutathione oxidized, used as chain extender, were synthetized. Three different reactions conditions were investigated using three different copolymers having ɛ-CL/polyethylene glycol molar ratios equal to 12, 24 and 36 and three different reaction conditions. As investigated by size exclusion chromatography analyses and quantification of l -glutathione, the polymerization and the extension phase's efficiency depended on the ɛ-CL/PEG ratio and the extension phase's operating temperature. Three selected polyurethanes were characterized by spectroscopic, differential scanning calorimetry (DSC) and…