Search results for "controlled release"

Designing Medical Devices Based on Silicon Polymeric Material with Controlled Release of Local Anesthetics

2012

The drug delivery systems that are the object of this article take the form of a polymer matrix made of silicone containing a drug. These devices can be used as patches for local dermal applications releasing the drug in a controlled manner. The model active agent, lidocaine hydrochloride was chosen from the range of local anesthetics. When the drug is restricted to the surface, it is released more rapidly than when it is allowed to spread evenly throughout the silicon structure. When hydrophilic polymers such as PVA and HEC are mixed in with the lidocaine hydrochloride and deposited on the surface of the polymer matrix, we observed that the burst effect was eliminated without modifying the…

Controlled Transdermal Release of Antioxidant Ferulate by a Porous Sc(III) MOF

2020

Summary The Sc(III) MOF-type MFM-300(Sc) is demonstrated in this study to be stable under physiological conditions (PBS), biocompatible (to human skin cells), and an efficient drug carrier for the long-term controlled release (through human skin) of antioxidant ferulate. MFM-300(Sc) also preserves the antioxidant pharmacological effects of ferulate while enhancing the bio-preservation of dermal skin fibroblasts, during the delivery process. These discoveries pave the way toward the extended use of Sc(III)-based MOFs as drug delivery systems (DDSs).

2021

The controlled release of antibiotics prevents the spread of pathogens and thereby improves healing processes in regenerative medicine. However, high concentrations may interfere with healing processes. It is therefore advantageous to use biodegradable materials for a controlled release. In particular, multilayer materials enable differential release at different surfaces. For this purpose, collagen sheets of different properties can be bonded by photochemical crosslinking. Here, we present the development and application of an easily accessible, additively manufactured sample holder to study the controlled release of vancomycin from modularly assembled collagen laminates in two directions.…

Optical Gating of Photosensitive Synthetic Ion Channels

2011

4-oxo-4-(pyren-4-ylmethoxy) butanoic acid is used as a photolabile protecting group to show the optical gating of nanofluidic devices based on synthetic ion channels. The inner surface of the channels is decorated with monolayers of photolabile hydrophobic molecules that can be removed by irradiation, which leads to the generation of hydrophilic groups. This process can be exploited in the UV-light-triggered permselective transport of ionic species in aqueous solution through the channels. The optical gating of a single conical nanochannel and multichannel polymeric membranes is characterised experimentally and theoretically by means of current-voltage and selective permeation measurements,…

PHEA-PLA biocompatible nanoparticles by technique of solvent evaporation from multiple emulsions

2015

Nanocarriers of amphiphilic polymeric materials represent versatile delivery systems for poorly water soluble drugs. In this work the technique of solvent evaporation from multiple emulsions was applied to produce nanovectors based on new amphiphilic copolymer, the α,β-poly(N-2-hydroxyethyl)-DL-aspartamide-polylactic acid (PHEA-PLA), purposely synthesized to be used in the controlled release of active molecules poorly soluble in water. To this aim an amphiphilic derivative of PHEA, a hydrophilic polymer, was synthesized by derivatization of the polymeric backbone with hydrophobic grafts of polylactic acid (PLA). The achieved copolymer was thus used to produce nanoparticles loaded with α toc…

Halloysite Nanotube with Fluorinated Lumen: Non-Foaming Nanocontainer for Storage and Controlled Release of Oxygen in Aqueous Media

2014

Halloysite clay nanotubes were selectivity modified by adsorbing perfluoroalkylated anionic surfactants at the inner surface. The modified nanotubes formed kinetically stable dispersions due to the enhanced electrostatic repulsions exercised between the particles. We proved that the modified nanotubes can be used as non-foaming oxygen nanocontainers in aqueous media. The gas release from supersaturated dispersions can be controlled by external stimuli and system composition. In conclusion, we managed to put forward an easy strategy to develop smart materials from natural nanoclays, which can endow important applications like the storage and delivery of gas.

Multi-Functional Nanogels for Tumor Targeting and Redox-Sensitive Drug and siRNA Delivery

2016

(1) Background: A new family of nanosystems able to discern between normal and tumor cells and to release a therapeutic agent in controlled way were synthetized by e-beam irradiation. This technique permits to obtain biocompatible, sterile, carboxyl-functionalized polyvinylpyrrolidone (PVP-co-acrylic acid) nanogels (NGs); (2) Methods: Here, we performed a targeting strategy based on the recognition of over-expressed proteins on tumor cells, like the folate receptor. The selective targeting was demonstrated by co-culture studies and flow cytometry analysis, using folate conjugated NGs. Moreover, nanoparticles were conjugated to a chemotherapeutic drug or to a pro-apoptotic siRNA through a gl…

Loading and release of the complex [Pt(DTBTA)(DMSO)Cl]Cl·CHCl3 with the 2,2′-dithiobis(benzothiazole) ligand into mesoporous silica and studies of an…

2018

Abstract Synthetic delivery systems have great potential for overcoming problems associated with systemic toxicity that accompanies chemotherapy with the use of cisplatin and family of platinum anticancer drugs. Mesoporous silicates have been studied in context of drug delivery and drug targeting. In this paper we report the studies of loading and release of a platinum complex, [Pt(DTBTA)(DMSO)Cl]Cl∙CHCl3 (1) where DTBTA = 2,2′-dithiobis(benzothiazole), that was recently synthesized and structurally characterized. Evaluation in vitro of antitumor activity against a human breast cancer cell line (MCF-7) showed a very potent activity of complex(1). Therefore, we thought to incorporate this co…

Selective, Highly Sensitive, and Rapid Detection of Genomic DNA by Using Gated Materials:MycoplasmaDetection

2013

The coupling of gated-indicator delivery with highly specific biochemical recognition is an innovative strategy for the detection of DNA sequences, able to compete with classical methods which need PCR amplification, in important areas such as point-of-care diagnostics or detection of specific biological contaminations with pathogens. Such comparatively simple and cheap yet highly selective and sensitive assays hold promise for use in less-developed areas of the world.

Halloysite Nanotubes and Metal Corrosion Inhibitors: A Computational and Experimental Study

2019

Halloysite nanotubes are widely used as a substrate for the controlled release of various types of molecules in an increasing number of applications. In this work, the interactions of halloysite silicic and aluminic surfaces with corrosion inhibitor compounds, such as benzotriazole, 8-hydroxyquinoline, 2-mercaptobenzimidazole, and 2-mercaptobenzothiazole, were investigated from a computational point of view. Two new halloysite compounds with salicylaldoxime and quinaldic acid were designed. Here we propose their synthesis, evaluate amounts of loading, and analyze the adsorption behavior.