Design, synthesis and membrane anchoring strength of lipidated polyaza crown ether DNA-conjugates (LiNAs) studied by DNA-controlled assembly of liposomes.

Hybridization-controlled assays for assembly or fusion of liposomes are versatile for detection of both DNA and RNA targets and useful for the evaluation of membrane anchoring strength of LiNAs with applications in the context of liposome assembly, liposome fusion and lipid nanoparticle formulation of therapeutic LiNAs. Herein, we report the synthesis of lipid phosphoramidite building blocks for automated LiNA synthesis and a study on design requirements for efficient lipid membrane anchoring and liposome assembly dependent on lipid membrane anchor length (C-C) and structure, the effect of internal linkers and locked nucleic acids (LNA) building blocks on the lipid membrane anchoring strength of LiNAs.

Quantification of the anti-neoplastic polyacetylene falcarinol from carrots in human serum by LC-MS/MS.

Falcarinol is a polyacetylene which is found in carrots and known to have anti-neoplastic properties in rodents. Research in the bioactivity of falcarinol in humans require methods for quantification of falcarinol in human serum. Here we report the development of an LC-MS/MS method and its use to measure serum falcarinol concentrations in humans following intake of a carrot product.

Lipidated Polyaza Crown Ethers as Membrane Anchors for DNA-Controlled Content Mixing between Liposomes.

The ability to manipulate and fuse nano-compartmentalized volumes addresses a demand for spatiotemporal control in the field of synthetic biology, for example in the bottom-up construction of (bio)chemical nanoreactors and for the interrogation of enzymatic reactions in confined space. Herein, we mix entrapped sub-attoliter volumes of liposomes (~135 nm diameter) via lipid bilayer fusion, facilitated by the hybridization of membrane-anchored lipidated oligonucleotides. We report on an improved synthesis of the membrane-anchor phosphoramidites that allows for a flexible choice of lipophilic moiety.

A global call for action to include gender in research impact assessment.

Global investment in biomedical research has grown significantly over the last decades, reaching approximately a quarter of a trillion US dollars in 2010. However, not all of this investment is distributed evenly by gender. It follows, arguably, that scarce research resources may not be optimally invested (by either not supporting the best science or by failing to investigate topics that benefit women and men equitably).

Mismatch discrimination of lipidated DNA and LNA-probes (LiNAs) in hybridization-controlled liposome assembly.

Assays for mismatch discrimination and detection of single nucleotide variations by hybridization-controlled assembly of liposomes, which do not require tedious surface chemistry, are versatile for both DNA and RNA targets. We report herein a comprehensive study on different DNA and LNA (locked nucleic acids) probe designs, including membrane-anchoring requirements, studies on different probes and target lengths (including overhangs), DNA and RNA targets (including sequences associated with pathogens) for lipidated nucleic acids (LiNAs). Advantages and limitations of the liposome assembly based assay in the context of mismatch discrimination and SNP detection are presented.

Assembly of liposomes controlled by triple helix formation.

Attachment of DNA to the surface of different solid nanoparticles (e.g., gold and silica nanoparticles) is well established, and a number of DNA-modified solid nanoparticle systems have been applied to thermal denaturation analysis of oligonucleotides.

Site-directed spin-labeling of nucleic acids by click chemistry: detection of abasic sites in duplex DNA by EPR spectroscopy.

This paper describes a spin label that can detect and identify local structural deformations in duplex DNA, in particular abasic sites. The spin label was incorporated into DNA by a new postsynthetic approach using click-chemistry on a solid support, which simplified both the synthesis and purification of the spin-labeled oligonucleotides. A nitroxide-functionalized azide, prepared by a short synthetic route, was reacted with an oligomer containing 5-ethynyl-2'-dU.

Chapter 12 - DNA-controlled assembly of liposomes in diagnostics.

DNA-encoding of solid nanoparticles requires surface chemistry, which is often tedious and not generally applicable. In the presented method, noncovalent attachment of DNA is used to assemble soft nanoparticles (liposomes) in solution. This process displays remarkably sharp thermal transitions from the assembled to disassembled state, thus enabling easy and fast detection of polynucleotides (e.

DNA controlled assembly of soft nanoparticles.

DNA-encoding of solid nanoparticles requires surface-chemistry, which is often tedious and not generally applicable. In the present study non-covalently attached DNA are used to assemble soft nanoparticles (liposomes) in solution. This process displays remarkably sharp thermal transitions from assembled to disassembled state for which reason this method allows easy and fast detection of polynucleotides (e.

Lipophilic DNA-conjugates: DNA controlled assembly of liposomes.

DNA detection systems based on encoded solid particles have been reported but require often tedious and not generally applicable surface chemistry. In the present study a system comprised of a lipid-modified DNA probe sequence and unmodified DNA target sequences is used to non-covalently assemble liposomes. The process results in large liposome aggregates with dramatically different optical properties compared to individual liposomes in solution.

DNA controlled assembly of liposomes.

DNA-encoding of solid nanoparticles requires surface-chemistry, which is often tedious and not generally applicable. In the present study non-covalently attached DNA are used to assemble soft nanoparticles (liposomes) in solution. This process displays remarkably sharp thermal transitions from assembled to disassembled state for which reason this method allows easy and fast detection of polynucleotides (e.

DNA-controlled assembly of soft nanoparticles.

Immobilization of DNA (encoding) on solid nanoparticles requires surface chemistry, which is well established for gold surfaces but often tedious and not generally applicable for many other inorganic surface materials. While substantial effort has been devoted to expanding surface chemistry techniques for solid nanoparticles, considerably less attention has been given to the development of noncovalent attachment of DNA to soft nanoparticles, like liposomes. Here we report a DNA-controlled assembly of liposomes in solution and on solid supported membranes, this process displays remarkably sharp thermal transitions from an assembled to a disassembled state, allowing application of DNA-controlled liposome assembly for the detection of polynucleotides (e.

Toward a catalytic site in DNA: polyaza crown ether as non-nucleosidic building blocks in DNA conjugates.

A number of functionalized polyaza crown ether building blocks have been incorporated into DNA-conjugates as catalytic Cu(2+) binding sites. The effect of the DNA-conjugate catalyst on the stereochemical outcome of a Cu(2+)-catalyzed Diels-Alder reaction will be presented.

Polyaza crown ether as non-nucleosidic building blocks in DNA-conjugates.

The synthesis of amphiphilic polyaza crown ether monomers X (palmityl-substituted), Y (cholesteryl-substituted) and Z (dipalmityl-subtituted) and their incorporation into oligonucleotides are described. Their effects on thermal duplex stability were investigated by UV melting curve analysis. Thermal denaturation experiments showed remarkable stabilization of dsDNA by polyaza crown ether monomers when incorporated in opposite positions.

Dietary habits and nutritional status of renal transplant patients.

Background: Although dialysis nutritional problems are well described, nutritional problems after renal transplantation (RT) have received little attention.

Methods: Body composition as assessed by dual-energy x-ray absorptiometry in 115 stable patients 6.6 +/- 5.