The spin dynamics of dissolution DNP samples consisting of 4.5 M [13C]urea in a mixture of (1/1)Vol glycerol/water using 4-Oxo-TEMPO as a radical was investigated. We analyzed the DNP dynamics as function of radical concentration at 7 T and 3.4 T static magnetic field as well as function of deut...

BackgroundThe Institute of Medicine calls for meaningful collaboration between doctor of nursing practice (DNP)- and doctor of philosophy (PhD)-prepared nurses to improve health outcomes.

Dynamic nuclear polarization (DNP) enhanced nuclear magnetic resonance (NMR) offers a promising route to studying local atomic environments at the surface of both crystalline and amorphous materials. We take advantage of unpaired electrons due to defects close to the surface of the silicon micro...

The development of new, high-frequency solid-state diode sources capable of operating at 263 GHz, together with an optimized stator design for improved millimeter-wave coupling to the NMR sample, have enabled low-power DNP experiments at 263 GHz/400 MHz. With 250 mW output power, signal enhancem...

We consider the geometry of a radially irradiated microwave beam in MAS DNP NMR probes and its impact on DNP enhancement. Two related characteristic features are found to be relevant: (i) the focus of the microwave beam on the DNP MAS sample and (ii) the microwave magnetic field magnitude in the...

Overhauser dynamic nuclear polarization (DNP) is the dominating hyperpolarization technique to increasing the nuclear magnetic resonance signal in liquids and diluted systems. The enhancement obtained depends on the overall mobility of the radical-carrying molecule but also on its specific inter...

Dynamic Nuclear Polarization (DNP) is an effective approach to alleviate the inherently low sensitivity of solid-state NMR (ssNMR) under magic angle spinning (MAS) towards large-sized multi-domain complexes and assemblies. DNP relies on a polarization transfer at cryogenic temperatures from unpa...

Biological mineralized tissues are hybrid materials with complex hierarchical architecture composed of biominerals often embedded in an organic matrix. The atomic-scale comprehension of surfaces and organo-mineral interfaces of these biominerals is of paramount importance to understand the ultra...

Solid-state NMR spectroscopy is a powerful technique for the characterization of the atomic-level structure and dynamics of materials. Nevertheless, the use of this technique is often limited by its lack of sensitivity, which can prevent the observation of surfaces, defects or insensitive isotop...

A high performance liquid chromatographic procedure was developed to determine folic acid and its photodegradation products, p-aminobenzoic acid, pterine-6-carboxylic acid, p-aminobenzoyl-l-glutamic acid, and pteroic acid in the presence of riboflavin. The method involves reversed phase, paired-...

Using the fast optical technique of laser flash photolysis by a kinetic absorption detector, the photophysical and photochemical processes of folic acid have been observed. By comparison of transient absorptions from photolysis between folic acid and its components, pteroic acid, pterin and 6-ca...

N10-Trifluoroacetylpteroic acid was conjugated to chemiluminescent N-sulfonylacridinium-9-carboxamide labels at the N10 or 9-position carboxamide. Upon binding to folate binding protein the light output of the N10 derivative (9) was quenched up to 62% upon triggering with basic peroxide, while t...

A TLC method was developed that allows the evaluation of the 7,8-dihydropteroate synthase reaction via determination of the stable pteroic acid (PtA), obtained by chemical oxidation of the enzymatic product dihydropteroic acid (H2PtA). Using amino-bonded HPTLC plates and solution of 52% acetonit...

Crude pteroic acid, obtained by microbiological degradation of folic acid, has been purified by column chromatography on cellulose CF11, eluting with 0.1 M glycine buffer of pH 10.0, containing 0.15% w/v ascorbic acid and saturated with isoamyl alcohol.

Publisher SummaryThis chapter describes the preparation and purification of pteroic acid from pteroylglutamic acid (folic acid). Pteroic acid can be prepared conveniently, by the removal of glutamic acid, from commercially available pteroyiglutamic acid, using a pteroylglutamic acid-degrading ps...

As a first step in the process of developing folate based visual probes and contrast agents, we have designed and synthesised a series of first generation lanthanide(III) molecular probes. The molecular probe structure included a lanthanide(III) (Eu(III), Tb(III), Gd(III)) chelate which was link...

Enhanced intracellular internalization of the anti-cancer active idarubicin (IDA) was achieved through appropriate surface modification of IDA loaded propyl starch nanoparticles. This was conducted by synthesizing pteroic acid modified polyvinyl alcohol (ptPVA) and employing this stabilizer for ...

The complexation of pteroic acid and pterine, subunits of folic acid, with native cyclodextrins (α‒, β‒, and γ‒CDs) was studied in solution (UV–vis), and in the solid state (thermal analysis, IR and Raman). UV–vis titrations at pH = 7.4 provided data regarding stoichiometry of the formed co...

Histone deacetylase (HDAC) inhibition has recently emerged as a novel therapeutic approach for the treatment of various pathological conditions including cancer. Currently, two HDAC inhibitors (HDACi) – Vorinostat and Romidepsin – have been approved for the treatment of cutaneous T-cell lympho...

In order to fully understand the dependence of device electroluminescence (EL) on the chemical structure of two light-emitting materials: 1,2,3,4-tetraphenyl-1,3-cyclopentadiene (TPCP) and 1,2,3,4,5-pentaphenyl-1,3-cyclopentadiene (PPCP), their properties in solution and as evaporated thin films...