Liquid chromatography/ultraviolet (LC/UV) and mass spectrometry/mass spectrometry (MS/MS) libraries containing 39 phenolic compounds were established by coupling a LC and an ion trap MS with an electrospray ionization (ESI) source, operated in negative ion mode. As a result, the deprotonated [M-H] -molecule was observed for all the analyzed compounds. Using MS/MS hydroxybenzoic acid and hydroxycinnamic acids showed a loss of CO 2 and production of a [M-H-44] -fragment and as expected, the UV spectra of these two compounds were affected by their chemical structures. For flavonol and flavonol glycosides, the spectra of their glycosides and aglycones produced deprotonated [M-H] -and [A-H] -species, respectively, and their UV spectra each presented two major absorption peaks. The UV spectra and MS/MS data of flavan-3-ols and stilbenes were also investigated. Using the optimized LC/MS/MS analytical conditions, the phenolic extracts from six representative wine samples were analyzed and 31 phenolic compounds were detected, 26 of which were identified by searching the LC/UV and MS/MS libraries. Finally, the presence of phenolic compounds was confirmed in different wine samples using the LC/UV and LC/MS/MS libraries. Molecules, 2007, 12 680

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The main purpose of current investigation is to prepare a self-microemulsifying drug delivery system (SMEDDS) to enhance the oral bioavailability of vinpocetine, a poorly water-soluble drug. Suitable vehicles were screened by determining the solubility of vinpocetine in them. Certain surfactants were selected according to their emulsifying ability with different oils. Ternary phase diagrams were used to identify the efficient self-microemulsifying region and to screen the effect of surfactant/cosurfactant ratio (K(m)). The optimized formulation for in vitro dissolution and bioavailability assessment was oil (ethyl oleate, 15%), surfactant (Solutol HS 15, 50%), and cosurfactant (Transcutol P, 35%). The release rate of vinpocetine from SMEDDS was significantly higher than that of the commercial tablet. Pharmacokinetics and bioavailability of SMEDDS were evaluated. It was found that the oral bioavailability of vinpocetine of SMEDDS was 1.72-fold higher as compared with that of the commercial tablet. These results obtained demonstrated that vinpocetine absorption was enhanced significantly by employing SMEDDS. Therefore, SMEDDS might provide an efficient way of improving oral bioavailability of poorly water-soluble drugs.

Grafting three types of polymer chains onto the backbone of a fourth polymer yielded a ternary graft copolymer. The copolymer dispersed oil droplets in water with one type of graft stretching into the oil phase, the second type forming a thin membrane separating the two phases, and the third type stretching into the water phase. Since the second type was also photo-cross-linkable, shining UV light on the system produced permanent nanocapsules. To produce the graft copolymer, the backbone polymer used was poly(3-azido-2-hydroxypropyl methacrylate), P(GMA-N 3 ). The grafts used were all end-functionalized by alkyne groups, and the polymers were poly(ethylene glycol) methyl ether (MPEG), polystyrene (PS), and poly(2-cinnamoyloxyethyl methacrylate) (PCEMA), respectively. Evidently, MPEG was water-soluble, PS was soluble in the used oil decahydronaphthalene (DN), and PCEMA was photo-cross-linkable and soluble in neither water nor DN. The grafts denoted as MPEG−CCH, PS−CCH, and PCEMA−CCH were coupled to P(GMA-N 3 ) via click chemistry between the azide and alkyne units. Under the used conditions, the one-pot grafting reactions were quantitative.

Pyrolysis is a promising approach that is being investigated to convert lignin into higher value products including biofuels and phenolic chemicals. In this study, fast pyrolysis of four types of lignin, including milled Amur linden wood lignin (MWL), enzymatic hydrolysis corn stover lignin (EHL), wheat straw alkali lignin (AL) and wheat straw sulfonate lignin (SL), were performed using pyrolysis gas-chromatography/mass spectrometry (Py-GC/MS). Thermogravimetric analysis (TGA) showed that the four lignins exhibited widely different thermolysis behaviors. The four lignins had similar functional groups according to the FTIR analysis. Syringyl, guaiacyl and p-hydroxyphenylpropane structural units were broken down during pyrolysis. Fast pyrolysis product distributions from the four lignins depended strongly on the lignin origin and isolation process. Phenols were the most abundant pyrolysis products from MWL, EHL and AL. However, SL produced a large number of furan compounds and sulfur compounds originating from kraft pulping. The effects of pyrolysis temperature and time on the product distributions from corn stover EHL were also studied. At 350 °C, EHL pyrolysis mainly produced acids and alcohols, while phenols became the main products at

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