Search results for " Delivery system"
showing 10 items of 350 documents
A biphasic calcium phosphate coating for potential drug delivery affects early osseointegration of titanium implants.
2016
Background Calcium phosphate (CaP) surface coatings may accelerate osseointegration and serve as a drug delivery system for mineral-binding biomolecules. In a pilot study, the impact of a commercially available, thin CaP coating on early osseous bone remodeling was compared with a modern, subtractive-treated rough surface (SLA-like) in an animal trial. Methods In 16 rabbits, 32 endosseous implants (CaP; n = 16, SLA-like; n = 16) were bilaterally inserted in the proximal tibia after randomization. After 2 and 4 weeks, bone-implant contact (BIC;%) in the cortical (cBIC) and the trabecular bone (sBIC) as well as volume of bone within the screw thread with the highest amount of new-formed bone …
Biocompatible hydrogels based on hyaluronic acid cross-linked with a polyaspartamide derivative as delivery systems for epithelial limbal cells.
2011
The aim of this work was to evaluate the potential use of hydrogels based on hyaluronic acid (HA) chemically cross-linked with α,β-poly(N-2-hydroxyethyl) (2-aminoethylcarbamate)-D,L-aspartamide (PHEA-EDA) as substitutes for the amniotic membrane able to release limbal cells for corneal regeneration. Hydrogels, shaped as films, with three different molar ratios (X) between PHEA-EDA and HA (X = 0.5, 1.0 and 1.5) have been investigated. First, it has been evaluated their swelling ability, hydrolytic resistance in simulated physiological fluid and cell compatibility by using human dermal fibroblasts chosen as a model cell line. Then adhesion studies in comparison with collagen gel, have been pe…
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.
Novel Lipid and Polymeric Materials as Delivery Systems for Nucleic Acid Based Drugs
2015
Nucleic acid based drugs (NADBs) are short DNA/RNA molecules that include among others, antisense oligonucleotides, aptamers, small interfering RNAs and micro-interfering RNAs. Despite the different mechanisms of actions, NABDs have the ability to combat the effects of pathological gene expression in many experimental systems. Thus, nowadays, NABDs are considered to have a great therapeutic potential, possibly superior to that of available drugs. Unfortunately, however, the lack of effective delivery systems limits the practical use of NABDs. Due to their hydrophilic nature, NABDs cannot efficiently cross cellular membrane; in addition, they are subjected to fast degradation by cellular and…
A comparative study of the physicochemical properties of iron isomaltoside 1000 (Monofer®), a new intravenous iron preparation and its clinical impli…
2011
Abstract The treatment of iron deficiency anemia with polynuclear iron formulations is an established therapy in patients with chronic kidney disease but also in other disease areas like gastroenterology, cardiology, oncology, pre/post operatively and obstetrics’ and gynecology. Parenteral iron formulations represent colloidal systems in the lower nanometer size range which have traditionally been shown to consist of an iron core surrounded by a carbohydrate shell. In this publication, we for the first time describe the novel matrix structure of iron isomaltoside 1000 which differs from the traditional picture of an iron core surrounded by a carbohydrate. Despite some structural similaritie…
Selective, Sensitive, and Rapid Analysis with Lateral-Flow Assays Based on Antibody-Gated Dye-Delivery Systems: The Example of Triacetone Triperoxide
2013
[EN] Antibodygated MSNs that are loaded with a rhodamine dye and that can be used for the determination of the presence of peroxide-based explosive TATP with a lateral-flow fluorescence reader have been designed and prepared, thereby allowing for detection limits in the lower ppb range. The mechanism of the detection relies on a displacement of the antibody from the surface of the hybrid material because of highly affine antibody-TATP interactions, which release a much larger number of entrapped dye molecules from the pores than antibodies are displaced. The high selectivity of the antibody is retained in the gated material, thus allowing for a remarkable discrimination against H2O2. System…
Intestinal absorption enhancement via the paracellular route by fatty acids, chitosans and others: a target for drug delivery.
2005
Peroral delivery of hydrophilic drugs is one of the greatest challenges in biopharmaceutical research. Hydrophilic drugs usually present low bioavailability after oral administration. One of the causes of this low bioavailability is their poor intestinal permeation through the paracellular pathway. This pathway is actually restricted by the presence of tight junctions at the apical side of the enterocytes. In the last few years, great interest has been focused on the structure and cellular regulation of tight junctions, materializing in more in-depth knowledge of this intestinal barrier. Simultaneously, and on the basis of this understanding, continuous efforts are being made to develop age…
In Vitro and In Silico Studies of Two 1,4-Naphthoquinones and Their Topical Formulation in Bigels.
2021
Background: 1,4-Naphthoquinones (1,4-NQs) are secondary plant metabolites with numerous biological activities. 1,4-NQs display low water solubility and poor bioavailability. Bigels are a new technology with great potential, which are designated as drug delivery systems. Biphasic bigels consisting of solid and liquid components represent suitable formulations improving diffusion and bioavailability of NQs into the skin. Objective: We evaluated the in silico and in vitro activity of 5,8-dihydroxy-1,4-naphthoquinone (M1) and 2,3-dichloro-5,8-dihydroxy-1,4-naphthoquinone (M2) on elastase and assessed their cytotoxicity towards COLO38 melanoma cells. The 1,4-NQs were loaded into bigels for topi…
Clay-biosurfactant materials as functional drug delivery systems: Slowing down effect in the in vitro release of cinnamic acid
2017
Abstract The main objectives of the present paper were the preparation and characterization of new surfactant-modified clays and the evaluation of their potential applicability as drug delivery systems for the oral administration of the cinnamic acid (CA) drug. The organoclays (OC) were prepared by loading different amounts of the biocompatible nonionic polyoxyethylene sorbitan monolaurate surfactant (Tween20) onto K10 montmorillonite (Mt) clay and characterized through the construction of the adsorption isotherms by means of the spectrophotometric method. The performance of the prepared material was verified by gathering the adsorption isotherms of the cinnamic acid onto the Mt/Tween20 org…
Supercritical Fluid Adsorption of Domperidone on Silica Aerogel
2013
Silica aerogel (SA) was loaded with domperidone 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. The effects of pressure, temperature and solution concentration on loaded SA were studied. Adsorption isotherms were measured at 35℃ and 45℃ and fitted with Langmuir model. Release kinetics of the adsorbed drug were also evaluated by in vitro dissolution tests. Results showed that domperidone can be uniformly dispersed into the aerogel and that the release rate of domperidone from the composite, constituted by drug and silica aerogel, is much faster than that…