Search results for "BIOCOMPATIBILI"

Polylactic is a Sustainable, Low Absorption, Low Autofluorescence Alternative to Other Plastics for Microfluidic and Organ-on-Chip Applications

2020

Organ-on-chip (OOC) devices are miniaturized devices replacing animal models in drug discovery and toxicology studies. The majority of OOC devices are made from polydimethylsiloxane (PDMS), an elastomer widely used in microfluidic prototyping, but posing a number of challenges to experimentalists, including leaching of uncured oligomers and uncontrolled absorption of small compounds. Here we assess the suitability of polylactic acid (PLA) as a replacement material to PDMS for microfluidic cell culture and OOC applications. We changed the wettability of PLA substrates and demonstrated the functionalization method to be stable over a time period of at least 9 months. We successfully cultured …

Hybrid assemblies based on a gadolinium-containing polyoxometalate and a cationic polymer with spermine side chains for enhanced MRI contrast agents.

2013

Supramolecular assembly: Spherical and stable hybrid assemblies based on a cationic polymer with spermine side chains and an anionic Gd(3+)-containing polyoxometalate cluster (GdW) are prepared by electrostatic interaction. The T1-weighted MRI performance of GdW is enhanced about three times in the assemblies; meanwhile, the assemblies show good biocompatibility, which enables them to be promising candidates for MRI contrast agents.

Recent advances on thermosensitive and pH-sensitive liposomes employed in controlled release

2019

Nanotechnology has recently gained lots of interest in drug delivery due to its potential to improve the therapeutic outcomes of various diseases. Particularly, a wide range of different nano-sized vesicles has been investigated for drug delivery. Among them, one of the most attractive and well-investigated nanocarriers are liposomes. Although liposomes have several advantages such as low toxicity, biodegradability and biocompatibility as well as accumulate in tumor site via enhanced permeability and retention (EPR) effect, inefficient drug delivery to the target cells could affect the therapeutic purpose of most of conventional liposomal formulations. Therefore, new systems of drug release…

Molecular Dynamics Simulations of the Initial Adsorption Stages of Fibrinogen on Mica and Graphite Surfaces.

2015

Fibrinogen, a blood glycoprotein of vertebrates, plays an essential role in blood clotting by polymerizing into fibrin when activated. Upon adsorption on material surfaces, it also contributes to determine their biocompatibility and has been implicated in the onset of thrombosis and inflammation at medical implants. Here we present the first fully atomistic simulations of the initial stages of the adsorption process of fibrinogen on mica and graphite surfaces. The simulations reveal a weak adsorption on mica that allows frequent desorption and reorientation events. This adsorption is driven by electrostatic interactions between the protein and the silicate surface as well as the counterion …

In vitro methodologies to evaluate biocompatibility: Status quo and perspectives

2007

Biocompatibility, hemocompatibility and antimicrobial properties of xyloglucan-based hydrogel film for wound healing application.

2018

Crosslinked xyloglucan-poly(vinyl alcohol) based hydrogel films are interesting materials for wound healing applications. This work focuses on the hydrolytic degradation and consequent morphological modification of a XG-PVA film and on its interaction with cells, blood, bacteria. Biocompatibility of the film was assessed in vitro by investigating different aspects, such as cell viability, oxidative stress level, mitochondrial dysfunction and specific stress biomarkers. Partial adhesiveness was demonstrated by performing different attaching assays and phalloidin staining. Hemocompatibility of XG-PVA film after interaction with blood was evaluated by using a multi-parametric approach, includi…

The Internal Dynamics and Early Adsorption Stages of Fibrinogen Investigated by Molecular Dynamics Simulations

2016

Fibrinogen, a plasma glycoprotein of vertebrates, plays an essential role in blood clotting by polymerizing into fibrin upon activation. It also contributes, upon adsorption on material surfaces, to determine their biocompatibility and has been implicated as a cause of thrombosis and inflammation at medical implants. Here we present the first fully atomistic simulations of the initial stages of the adsorption process of fibrinogen on mica and graphite surfaces. The simulations reveal a weak adsorption on mica that allows frequent desorption and reorientation events. This adsorption is driven by electrostatic interactions between the protein and the silicate surface as well as the counter io…

Polyhydroxyethylaspartamide-spermine copolymers: Efficient vectors for gene delivery

2008

Abstract Aim of this paper was that to prepare biocompatible, polyaspartamide based copolymers containing spermine or spermine/hydrophobic side chains able to condense nucleic acids and to transfect mammalian cells. Copolymers were prepared starting from α,β-poly-(N-2-hydroxyethyl)- d , l -aspartamide (PHEA) and exploiting the reactive hydroxyl groups in the polymeric side chains by subsequent activation reactions to obtain PHEA-Spermine (PHEA-Spm) and PHEA-Spermine-Butyramide (PHEA-Spm-C4). Molecular, physico-chemical and biological characterization of copolymers and interpolyelectrolyte complexes with plasmid DNA was performed. Experimental results evidenced that these copolymers are able…

Behavior of polyether-ether-ketone (PEEK) in prostheses on dental implants. A review.

2020

Background The development of new and innovative materials such as high performance polymers (PEEK) opens a wide therapeutic range in implant prostheses. They are presented as alternative materials to metal and zirconium alloys in the manufacture of structures and attachments for implant prostheses and fixed and removable dental substitutes. The objective of this review is to know the characteristics of this material and thus assess its advantages and disadvantages in its possible applications in prostheses on dental implants. Material and methods A bibliographic search was carried out through the PubMed and Scopus search engines, of articles published from 2007 to 2020, excluding all artic…

Hemoglobin loaded polymeric nanoparticles: preparation and characterizations.

2011

In the present work polymeric nanoparticles based on Poly (maleic anhydride-alt-butyl vinyl ether) 5% grafted with m-PEG (2000) and 95% grafted with 2-methoxyethanol (VAM41-PEG) were loaded with human hemoglobin (Hb) and characterized from a physicochemical point of view. The assessment of structural and functional features of the loaded Hb was performed and the effect of the introduction of different reducing agents as aimed at minimizing Hb oxidation during the nanoparticles formulation process, was also investigated. Nanoparticles possessing an average diameter of 138 ± 10 nm and physicochemical features suitable for this kind of application were successfully obtained. Although the oxida…