Search results for "Note"
showing 10 items of 10709 documents
Comparison of linear and hyperbranched polyether lipids for liposome shielding by 18F-radiolabeling and positron emission tomography
2018
Multifunctional and highly biocompatible polyether structures play a key role in shielding liposomes from degradation in the bloodstream, providing also multiple functional groups for further attachment of targeting moieties. In this work hyperbranched polyglycerol (hbPG) bearing lipids with long alkyl chain anchor are evaluated with respect to steric stabilization of liposomes. The branched polyether lipids possess a hydrophobic bis(hexadecyl)glycerol membrane anchor for the liposomal membrane. hbPG was chosen as a multifunctional alternative to PEG, enabling the eventual linkage of multiple targeting vectors. Different hbPG lipids (Mn = 2900 and 5200 g mol-1) were examined. A linear bis(h…
Steric Constraints Induced Frustrated Growth of Supramolecular Nanorods in Water.
2015
A unique example of supramolecular polymerisation in water based on monomers with nanomolar affinities, which yield rod-like materials with extraordinarily high thermodynamic stability, yet of finite length, is reported. A small library of charge-neutral dendritic peptide amphiphiles was prepared, with a branched nonaphenylalanine-based core that was conjugated to hydrophilic dendrons of variable steric demand. Below a critical size of the dendron, the monomers assemble into nanorod-like polymers, whereas for larger dendritic side chains frustrated growth into near isotropic particles is observed. The supramolecular morphologies observed by electron microscopy, X-ray scattering and diffusio…
Molecular association of small amphiphiles: Origin of ionic liquid properties in dibutyl phosphate/propylamine binary mixtures
2018
Abstract Binary mixtures of liquid surfactants, owing to the amphiphilic nature of the molecules involved, can exhibit nano-segregation and peculiar transport properties. The amphiphilicity, and consequently the resulting self-assembly, can be tuned by changing the length of the alkyl chains and the nature of the polar head group. So, in the present study, the structural and dynamic properties of dibutyl phosphate/propylamine liquid mixtures at various compositions have been investigated by Wide Angle X-ray Scattering (WAXS), FT-IR, rheometry and dielectric spectroscopy in order to study the intermolecular association taking place when alkylphosphates and alkylamines with a small apolar par…
A sustainable replacement for TiO2 in photocatalyst construction materials: Hydroxyapatite-based photocatalytic additives, made from the valorisation…
2018
The use of waste materials and by-products in building materials is of increasing importance to improve sustainability in construction, as is the incorporation of photocatalytic materials to both combat atmospheric pollution and protect the structures and façades. This work reports the innovative use of photocatalytic hydroxyapatite (HAp) based powders, derived from Atlantic codfish bone wastes, as an additive to natural hydraulic lime mortars. HAp is the main component of bone, and hence is non-toxic and biocompatible. This is the first time that such a calcium phosphate-based photocatalyst, or indeed any fish/marine derived wastes, have been added to building materials. A key factor is th…
Polymer-enhanced ultrafiltration for heavy metal removal: Influence of chitosan and carboxymethyl cellulose on filtration performances
2018
Abstract Reclaiming of wastewaters contaminated by heavy metals has become a major challenge over the last decades. For this reason, nanoporous membrane processes have awaken the interest of industry and local community, and the possible ways to improve their performances has become a priority goal for researchers. Metal removal enhancement by polymer addition is a potential way that is deeply investigated herein on nickel ion rejection with chitosan and carboxymethyl cellulose addition. Due to the vanishing of electrostatic interactions induced by the large amount of salt usually contained in effluents, ion rejection consequently drastically drops. However, it is highlighted that a suffici…
Recent advances in surface plasmon resonance biosensors for microRNAs detection
2020
miRNAs are a large family of non-coding RNAs which play important roles in translational and post-transcriptional regulation of gene expression and biological processes. Abnormal expression of miRNAs is related to the initiation and progression of different diseases which make them be promising candidates for early medical diagnostics. Thus, accurate detection of miRNAs has great significance for disorder diagnosis. Nevertheless, their intrinsic characteristics such as short sequence, low concentration and sequence homology challenge routine techniques. The detection assays need to be extremely sensitive and selective in small value of intricate RNA samples. Biosensor-based strategies have …
Production of Hev b5 as a fluorescent biotin-binding tripartite fusion protein in insect cells
2005
The presented green fluorescent protein and streptavidin core-based tripartite fusion system provides a simple and efficient way for the production of proteins fused to it in insect cells. This fusion protein forms a unique tag, which serves as a multipurpose device enabling easy optimization of production, one-step purification via streptavidin-biotin interaction, and visualization of the fusion protein during downstream processing and in applications. In the present study, we demonstrate the successful production, purification, and detection of a natural rubber latex allergen Hev b5 with this system. We also describe the production of another NRL allergen with the system, Hev b1, which fo…
Adsorption and Conformation Behavior of Biotinylated Fibronectin on Streptavidin-Modified TiOX Surfaces Studied by SPR and AFM
2011
It is well-known that protein-modified implant surfaces such as TiO(2) show a higher bioconductivity. Fibronectin is a glycoprotein from the extracellular matrix (ECM) with a major role in cell adhesion. It can be applied on titanium oxide surfaces to accelerate implant integration. Not only the surface concentration but also the presentation of the protein plays an important role for the cellular response. We were able to show that TiO(X) surfaces modified with biotinylated fibronectin adsorbed on a streptavidin-silane self-assembly multilayer system are more effective regarding osteoblast adhesion than surfaces modified with nonspecifically bound fibronectin. The adsorption and conformati…
Defined-size DNA triple crossover construct for molecular electronics: modification, positioning and conductance properties.
2011
We present a novel, defined-size, small and rigid DNA template, a so-called B-A-B complex, based on DNA triple crossover motifs (TX tiles), which can be utilized in molecular scale patterning for nanoelectronics, plasmonics and sensing applications. The feasibility of the designed construct is demonstrated by functionalizing the TX tiles with one biotin-triethylene glycol (TEG) and efficiently decorating them with streptavidin, and furthermore by positioning and anchoring single thiol-modified B-A-B complexes to certain locations on a chip via dielectrophoretic trapping. Finally, we characterize the conductance properties of the non-functionalized construct, first by measuring DC conductivi…
Protein-membrane interaction probed by single plasmonic nanoparticles.
2008
We present a nanosized and addressable sensor platform based on membrane coated plasmonic particles and show unequivocally the covering with lipid bilayers as well as the subsequent detection of streptavidin binding to biotinylated lipids. The binding is detected on membrane covered gold nanorods by monitoring the spectral shift by fast single particle spectroscopy (fastSPS) on many particles in parallel. Our approach allows for local analysis of protein interaction with biological membranes as a function of the lateral composition of phase separated membranes.