Search results for "drug delivery."

Stacking as a key property for creating nanoparticles with tunable shape: The case of squalenoyl-doxorubicin

2019

The development of elongated nanoparticles for drug delivery is of growing interest in recent years, due to longer blood circulation and improved efficacy compared to spherical counterparts. Squalenoyl-doxorubicin (SQ-Dox) conjugate was previously shown to form elongated nanoparticles with improved therapeutic efficacy and decreased toxicity compared to free doxorubicin. By using experimental and computational techniques, we demonstrate here that the specific physical properties of SQ-Dox, which include stacking and electrostatic interactions of doxorubicin as well as hydrophobic interactions of squalene, are involved in the formation of nanoassemblies with diverse elongated structures. We …

Nimesulide adsorbed on silica aerogel using supercritical carbon dioxide

2012

Silica aerogel (SA) was loaded with nimesulide, a drug model compound, to demonstrate the potentiality of adsorption processes based on the usage of supercritical carbon dioxide to treat poorly water-soluble drugs, forming new kinds of drug delivery systems. Adsorption isotherms and kinetics were measured and described by models. The effect of pressure, temperature and solution concentration on loaded SA were also studied. Modelling of kinetic data showed that the sorption process was best described by a pseudo-second-order model. The adsorption isotherm data were best fitted by the Freundlich isotherm. The drug/SA composites were characterized using scanning electron microscopy, X-ray micr…

Hybrid supramolecular gels of Fmoc-F/halloysite nanotubes: Systems for sustained release of camptothecin

2017

Supramolecular gel hybrids obtained by self-assembly of Fmoc-L-phenylalanine (Fmoc-F) in the presence of functionalized halloysite nanotubes (f-HNT) were obtained in biocompatible solvents and employed as carriers for the delivery of camptothecin (CPT) molecules. The synthesis of the new f-HNT material as well as its characterization are described. The properties of the hybrid hydrogels and organogels were analyzed by several techniques. The presence of small amounts of f-HNT allows good dispersion of the tubes and the subsequent formation of homogeneous gels. The experimental results show that f-HNT functions only as an additive in the hybrid gels and does not demonstrate gelator behavior.…

Cancer phototherapy in living cells by multiphoton release of doxorubicin from gold nanospheres

2020

Doxorubicin is a widely used but toxic cancer chemotherapeutic agent. In order to localize its therapeutic action and minimize side effects, it was covalently conjugated to peptide-encapsulated gold nanospheres by click-chemistry and then photo-released in a controlled fashion by a multiphoton process. Selective treatment of a chosen region in a 2D layer of U2Os cancer cells is shown by driving photorelease with 561 nm irradiation at mu W power. These results show promising directions for the development of practical applications based on nanocarriers that can ensure drug delivery with high spatial and temporal control.

Engineering of Nanofibrous Amorphous and Crystalline Solid Dispersions for Oral Drug Delivery

2018

Poor aqueous solubility (<0.1 mg/mL) affects a significant number of drugs currently on the market or under development. Several formulation strategies including salt formation, particle size reduction, and solid dispersion approaches have been employed with varied success. In this review, we focus primarily on the emerging trends in the generation of amorphous and micro/nano-crystalline solid dispersions using electrospinning to improve the dissolution rate and in turn the bioavailability of poorly water-soluble drugs. Electrospinning is a simple but versatile process that utilizes electrostatic forces to generate polymeric fibers and has been used for over 100 years to generate synthet…

Microfluidic production of hyaluronic acid derivative microfibers to control drug release

2016

"Available online 4 July 2016"

Silica-coated calcium pectinate beads for colonic drug delivery

2013

The aim of this work is to develop novel organic-inorganic hybrid beads for colonic drug delivery. For this purpose, calcium pectinate beads with theophylline are prepared by a cross-linking reaction between amidated low-methoxyl pectin and calcium ions. The beads are then covered with silica, starting from tetraethyoxysilane (TEOS), by a sol-gel process. The influence of TEOS concentration (0.25, 0.50, 0.75 and 1.00 M) during the process is studied in order to modulate the thickness of the silica layer around the pectinate beads and thus to control the drug release. The interactions between the silica coating and the organic beads are weak according to the physicochemical characterizations…

Self-assembled FeCo/gelatin nanospheres with rapid magnetic response and high biomolecule-loading capacity.

2009

Carbon Nanotubes

2019

Abstract Nanoparticles are increasingly being considered in the medical field as an effective means to deliver drugs of interest or as diagnostic biosensors. Carbon nanotubes (CNTs) are an allotropic form of carbon related to the fullerene family. Their exceptional thermal, mechanical, and electronical properties together with their tubular shape, offering a high surface area and enabling adsorption or conjugation of a wide variety of therapeutic drugs or diagnostic agents, make CNTs attractive platforms for the treatment of various diseases. This chapter reviews the emerging synthesis, characterization, and medical applications of CNTs and discusses the perspectives and obstacles of these …

Controlled Delivery of Gentamicin Antibiotic from Bioactive Electrospun Polylactide-Based Ultrathin Fibers

2011

The purpose of this study was to generate ultrathin fibers based on polylactide (PLA) biopolyester with antimicrobial controlled release capacity to treat bacterial infections. To achieve this objective, gentamicin antibiotic was encapsulated into pure PLA fibers, a blend of PLA–collagen and coaxial fibers containing a skin of PLA and a core of collagen using the electrospinning technique. The morphology of the gentamicin-loaded fibers and the antibiotic distribution within the fibers were examined by SEM and TEM. The drug delivery profile of the different electrospun fibers was analyzed using a spectrophotometric method. The performance for treating common possible post-surgical infections…