Qualitative and quantitative measurements of hydrogen bond mediated scalar couplings in acyclic 1,3-diols

[Structure: see text] OH...OH hydrogen bond mediated scalar couplings have been observed in acyclic syn- and anti-1,3-diols using a 2D 1H COSYLR NMR experiment and quantified with an uncertainty of +/-0.02 Hz with a selective-excitation spin-echo NMR experiment. A theoretical investigation confirmed the importance of the hydrogen bond in mediating the spin-spin coupling in these systems.     

Analysis of mannitol in pharmaceutical formulations using hydrophilic interaction liquid chromatography with evaporative light-scattering detection

This study demonstrates the use of hydrophilic interaction liquid chromatography (HILIC) for the separation of both active and inactive ingredients in pharmaceuticals from a single injection. Excipients commonly used in parenteral formulations were separated using a gradient method employing increasing aqueous composition. An evaporative light-scattering detector (ELSD) provided direct detection of inactive excipients and inorganic salts lacking UV chromophores. Analyses of Gemzar parenteral formulations using optimized isocratic HILIC-ELSD method conditions were performed based on retention time screening from the gradient assay. All of the components were efficiently separated using a TSK-Gel Amide 80 column including gemcitabine, mannitol, and sodium cation demonstrating the qualitative capability of the technique. The method was thoroughly validated for mannitol content to access the quantitative potential of the technique. Validation parameters included linearity, accuracy, specificity, solution stability, repeatability, and intermediate precision. Overall, the method described in this report proved to be very robust and represents a novel technique to conveniently separate and detect the active and inactive components in pharmaceuticals both quickly and accurately.     

Studies of the effects of neonatal exposure to genistein on the developing female reproductive system

Studies have shown that developmental exposure to genistein alters murine reproductive differentiation, resulting in abnormal ovarian development (multioocyte follicles) and uterine neoplasia later in life. Further, reproductive function was altered. Prolonged estrous cyclicity was observed following neonatal genistein treatment (0.5-50 mg/kg) on Days 1-5 with dose- and age-related increase in severity. Fertility, determined at 2, 4, and 6 months, showed decreased numbers of genistein-treated females (0.5 or 5 mg/kg) delivering live pups and reduced numbers of pups. At 6 months, 60% of 0.5 mg/kg and 40% of 5 mg/kg groups delivered live pups compared to 100% of controls. At 2 months, half the mice treated with 25 mg/kg of genistein and none treated with 50 mg/kg delivered live pups, although half of the latter group showed signs of pregnancy with few small implantation sites. Ovarian function was disrupted in the low genistein-dosed mice with increased numbers of corpora lutea (CLs) compared to controls and increased ovulated oocytes following exogenous gonadotropins treatment. In contrast, mice treated with high genistein doses had decreased numbers of CLs; ovulation could be restored with exogenous gonadotropins. Thus, neonatal treatment with genistein at environmentally relevant doses caused adverse consequences on ovarian development and reproductive function.     

Generation and structural analysis of reactive empty particles derived from an icosahedral virus

Chemical and genetic modifications on the surface of viral protein cages confer unique properties to the virus particles with potential nano and biotechnological applications. The enclosed space in the interior of the virus particles further increases its versatility as a nanomaterial. In this paper, we report a simple method to generate a high yield of stable cowpea mosaic virus (CPMV) empty capsids from their native nucleoprotein counterparts by removing the encapsidated viral genome without compromising the integrity of the protein coat. Biochemical and structural comparison of artificially generated empty particles did not reveal any distinguishable differences from CPMV particles containing viral RNA. Preliminary results on the use of artificially produced empty CPMV capsids as a carrier capsule are described.     

Photooxidation of Co-thiolato complexes in protic and aprotic solvents

Protic solvents decrease the susceptibility of the thiolate ligand in Co(III) thiolato complexes toward attack by singlet oxygen, but greatly increase the conversion of the peroxidic intermediate to the sulfenato product.     

Molecular Versus Conventional Kinetics of Emulsion Polymerization

Summary: Experimental data are discussed challenging the deterministic kinetics of emulsion polymerization. Examples are given for the overall rate of polymerization, in-situ stabilizer formation, and swelling of latex particles. Improving the deterministic view on emulsion polymerization kinetics requires the consideration of results of molecular modelling and the application of multiscale integration techniques.