This study explores the layer-by-layer (LBL) modification of polyacrylonitrile (PAN) hollow fibers for effective Mg/Li separation. It employs an LBL method of surface modification using polyelectrolytes, specifically aiming to enhance ion selectivity and improve the efficiency of lithium extraction from brines or lithium battery wastes, which is critical for battery recycling and other industrial applications. The modification process involves coating the hydrolyzed PAN fibers with alternating layers of positively charged polyelectrolytes, such as poly(allylamine hydrochloride) (PAH), polyethyleneimine (PEI), or poly(diallyldimethylammonium chloride) (PDADMAC) and negatively charged polyelectrolytes, such as poly(styrene sulfonate) (PSS), to form polyelectrolyte multilayers (PEMs).
View Article and Find Full Text PDFPolymers (Basel)
October 2024
Biopolymer chitosan sub-micron particles (CSMPs) were prepared by the ionic gelation technique crosslinked with sodium tripolyphosphate co-loaded with trans-cinnamaldehyde (TCIN), and either curcumin (CUR) or paclitaxel (PTX). The size of the spherical CSMPs increased from 118 nm to 136 nm and 170 nm after the loading of TCIN and CUR, whereas the loading of PTX led to a slight decrease (114 nm). Polydispersity indexes of all the samples were smaller than 0.
View Article and Find Full Text PDFThe ionic gelation method was used to study the effect of the crosslinking agent, sodium tripolyphosphate on average particle size (Dp) and zeta potential (ζp) of chitosan microparticles (CSMP) unloaded and loaded with trans-cinnamaldehyde (TCIN). The obtained values of Dp and ζp trend as 117.6 ± 0.
View Article and Find Full Text PDFSuberin is a biopolyester that can be extracted from bioresources such as cork trees and may find many applications in food packaging, sealing, and biomedical fields. In this work, we describe for the first time the preparation of suberin nanoparticles using the solvent/antisolvent method. Three different suberin extraction methods from cork trees were used to reveal any differences in the production and properties of the nanoparticles.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
December 2018
This study aimed to obtain bioactive nanosystems by combining cellulose acetate with three selected essential oils (EOs) to create spherical nanocapsules (NCs) using the solvent/anti-solvent technique. The biological activity of the obtained NCs was promoted by the use of some antimicrobial EOs: Peppermint, Cinnamon and lemongrass which were grafted on the cellulose acetate molecules. Due to their chemistry, such as long hydrocarbon tails and heads with functional groups these EOs were playing also the role of surfactant-like substance facilitating the formation of NCs.
View Article and Find Full Text PDFThe method of electrospinning was used to create nanofibers made of cellulose acetate (CA) and essential oils (EOs). CA polymer at 15% / was dissolved in acetone and then 1% or 5% / of EOs was added to the polymer solution. The utilized essential oils were rosemary and oregano oils.
View Article and Find Full Text PDFAmphiphilic chitosans have been recently proposed to improve delivery of poorly soluble drugs. In the present paper a derivative obtained by ionic interaction between chitosan and oleic acid was for the first time studied to physically stabilize o/w nanoemulsions of an antimicrobial essential oil, Cymbopogon citratus (Lemongrass), in a low energy and mild conditions emulsification process. The novel combination of spontaneous emulsification process with chitosan oleate amphiphilic properties resulted in a stable dispersion of a few hundred nanometer droplets.
View Article and Find Full Text PDFBeilstein J Nanotechnol
December 2016
The localization of light known as Anderson localization is a common phenomenon characterizing aggregates of metallic nanostructures. The electromagnetic energy of visible light can be localized inside nanostructures below the diffraction limit by converting the optical modes into nonradiative surface plasmon resonances. The energy of the confined photons is correlated to the size and shape of the nanostructured system.
View Article and Find Full Text PDFPolylactic acid was combined with lemongrass essential oil (EO) to produce functional nanocapsules (NCs). The obtained polylactic acid nanoparticles showed antimicrobial activity both with and without the presence of lemongrass oil; however, the presence of EO improved the activity of the NCs. The presence of lemongrass assisted the formation of well-separated NCs and also provided enhanced antimicrobial properties, since lemongrass is known for its antimicrobial character.
View Article and Find Full Text PDFCellulose acetate (CA) nanoparticles were combined with two antimicrobial agents, namely lemongrass (LG) essential oil and Cu-ferrite nanoparticles. The preparation method of CA nanocapsules (NCs), with the two antimicrobial agents, was based on the nanoprecipitation method using the solvent/anti-solvent technique. Several physical and chemical analyses were performed to characterize the resulting NCs and to study their formation mechanism.
View Article and Find Full Text PDFNanocapsules and nanoparticles play an essential role in the delivery of pharmaceutical agents in modern era, since they can be delivered in specific tissues and cells. Natural polymers, such as cellulose acetate, are becoming very important due to their availability, biocompatibility, absence of toxicity and biodegradability. In parallel, essential oils are having continuous growth in biomedical applications due to the inherent active compounds that they contain.
View Article and Find Full Text PDFThe broad utilization of electrospun scaffolds of sodium alginate in tissue engineering is strongly limited by their high solubility in aqueous environments and by the difficulty to adjust their degradation dynamics. Here, an alternative strategy to enhance the stability and to control the degradability of alginate nanofibers is described by treating them with trifluoroacetic acid for specific time intervals. It is demonstrated that, by increasing the duration of the acid treatment procedure, a lower degradation rate of the resulting fibers in buffer solutions can be achieved.
View Article and Find Full Text PDFBoron nitride nanotubes (BNNTs) have generated considerable interest among the scientific community because of their unique physical and chemical properties. They present good chemical inertness, high thermal stability, and optimal resistance to oxidation, that make them ideal candidates for biomedical applications, in particular as nanovectors for drug, gene and protein delivery into the cells. In this study, BNNTs were prepared through a synthesis based on a chemical vapor deposition (CVD) method, and thereafter chemically functionalized with folic acid.
View Article and Find Full Text PDFIntroduction: The work presents the development of acellular scaffolds extemporaneously embedded with platelet lysate (PL), as an innovative approach in the field of tissue regeneration/reparation. PL embedded scaffolds should have a tridimensional architecture to support cell migration and growth, in order to restore skin integrity. For this reason, chondroitin sulfate (CS) was associated with sodium alginate (SA) to prepare highly porous systems.
View Article and Find Full Text PDFThis review highlights the current situation of antimicrobial resistance and the use of magnetic nanoparticles (MNPs) in developing novel routes for fighting infectious diseases. The most important two directions developed recently are: (i) improved delivery of antimicrobial compounds based on a drastic decrease of the minimal inhibition concentration (MIC) of the drug used independently; and (ii) inhibition of microbial attachment and biofilm development on coated medical surfaces. These new directions represent promising alternatives in the development of new strategies to eradicate and prevent microbial infections that involve resistant and biofilm-embedded bacteria.
View Article and Find Full Text PDFWe present natural polymeric composite films made of essential oils (EOs) dispersed in sodium alginate (NaAlg) matrix, with remarkable anti-microbial and anti-fungal properties. Namely, elicriso italic, chamomile blue, cinnamon, lavender, tea tree, peppermint, eucalyptus, lemongrass and lemon oils were encapsulated in the films as potential active substances. Glycerol was used to induce plasticity and surfactants were added to improve the dispersion of EOs in the NaAlg matrix.
View Article and Find Full Text PDFPurpose: Oxidative stress has been found to play a key role in several diseases, that range from cancer to neurodegenerative disorders. Besides traditional anti-oxidant agents, in recent years much attention has been focused on nanotechnological solutions, including cerium oxide nanoparticles (nanoceria).
Methods: Thanks to its extraordinary catalytic properties, nanoceria mimics the activity of superoxide dismutase and of catalase, therefore acting as a reactive oxygen species (ROS) scavenger in many biological contexts.
Stable surface modifications of polydimethylsiloxane (PDMS) are of crucial importance for the exploitation of the versatile physical properties of silicone in many biological applications. Surface hydrophobic recovery in fact poses severe time limitations to the observation of biological events and, in particular, to cell culturing. A novel method of stable modification of PDMS surface chemistry was therefore elaborated, relying on the use of genipin as a natural low-toxicity cross-linker, and involving free amine moieties.
View Article and Find Full Text PDFBiodegradable polymeric materials based on blending aqueous dispersions of natural polymer sodium alginate (NaAlg) and povidone iodine (PVPI) complex, which allow controlled antiseptic release, are presented. The developed materials are either free standing NaAlg films or Ca(2+)-cross-linked alginate beads, which properly combined with PVPI demonstrate antibacterial and antifungal activity, suitable for therapeutic applications, such as wound dressing. Glycerol was used as the plasticizing agent.
View Article and Find Full Text PDFJ Tissue Eng Regen Med
February 2015
In the last decade, the importance of topographic properties of extracellular environments has been shown to be essential to addressing cell response, especially when replacing damaged tissues with functional constructs obtained in vitro. In the current study, densely packed sub-micron poly(3-hydroxybutyrate) (PHB) fibres were electrospun with random and parallel orientations. PC12 pheochromocytoma cells that mimic central dopaminergic neurons and represent a model for neuronal differentiation were cultured on collagen-coated fibres to evaluate cell response dependence on substrate topography.
View Article and Find Full Text PDFRecombinant proteins represent a new and promising class of polymeric materials in the field of biomaterials research. An important model for biomaterial design is elastin, the protein accounting for the elasticity of several tissues. Human elastin-like polypeptides (HELPs) have been developed as recombinant versions of elastin with the purpose of enhancing some peculiar characteristics of the native protein, like self-assembling.
View Article and Find Full Text PDFA novel and simple method for the preparation of chemically functionalized boron nitride nanotubes (BNNTs) is presented. Thanks to a strong oxidation followed by the silanization of the surface through 3-aminopropyl-triethoxysilane (APTES), BNNTs exposing amino groups on their surface were successfully obtained. The efficacy of the procedure was assessed with EDS and XPS analyses, which demonstrated a successful functionalization of ~15% boron sites.
View Article and Find Full Text PDFThis paper summarizes recent data on the occurrence of major organic compounds (benzene, toluene, xylenes, styrene, acetaldehyde, formaldehyde, naphthalene, limonene, α-pinene and ammonia, classified by the European Commission's INDEX strategy report as the priority pollutants to be regulated) and evaluates accordingly cancer and non-cancer risks posed by indoor exposure in dwellings and public buildings in European Union (EU) countries. The review process indicated that significant differences in indoor air quality exist within and among the countries where data were available, indicating corresponding differences in sources and emission strength of airborne chemicals, identified or not. Conservative exposure limits were not exceeded for non-carcinogenic effects, except for formaldehyde; for carcinogenic agents the estimated risks were up to three orders of magnitude higher than the one (10(-6)) proposed as acceptable by risk management bodies.
View Article and Find Full Text PDFImproved biocompatibility and performance of biomedical devices can be achieved through the incorporation of bioactive molecules on device surfaces. Five structurally distinct pectic polysaccharides (modified hairy regions (MHRs)) were obtained by enzymatic liquefaction of apple (MHR-B, MHR-A and MHR-alpha), carrot (MHR-C) and potato (MHR-P) cells. Polystyrene (PS) Petri dishes, aminated by a plasma deposition process, were surface modified by the covalent linking of the MHRs.
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