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A simple and versatile method for fabricating nanopatterns by a lift-off procedure is demonstrated. The technique involves the use of molecular transfer lithography based on water-soluble templates to form a nanopatterned UV-curable material on a PMGI layer, which serves as an underlying resin suitable for lift-off processes. This bi-layer procedure is used for the fabrication of nickel patterns, which are subsequently used as a hard mask for plasma etch processing. Using this procedure, a two-dimensional TiO(2) photonic crystal layer with a 450 nm lattice constant is fabricated on Y(3)Al(5)O(12):Ce(3+) (YAG:Ce) yellow ceramic plate phosphor to enhance its forward emission. The yellow emission in the forward direction is improved by a factor of 3.5 compared to that of a conventional non-scattering YAG:Ce phosphor plate excited by a blue LED.

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A simple, rapid and fully automated flow injection method (FIA) with chemiluminescence detection after oxidation with KMnO4 in acid medium at room temperature has been developed for the determination of routine in pharmaceutical formulation. Hexamethaphosphate sodium was utilized as enhancer of chemiluminescence. The calibration curve was linear in the range 0.01-0.26 mmol.l-1 with detection limit 0.005 mmol.l-1, RSD 0.46% (n = 10) and a sample throughput of 75.h-1 using a 200 microliters sample volume. The method was used for the determination of routine in mass-produced dosage form: Rutin 250 tablets á 50 mg, (firm Nature's Bounty, USA). The FIA method was statistically compared with the official German Pharmacopoeia method and showed comparable accuracy, but with the advantages of simplicity, speed and amounts of reagents consumed.

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The sequential injection (SIA) technique was applied in pharmacokinetic studies of the transporter-mediated passage of a model substrate, rhodamine 123 (Rho123), through the dually perfused rat term placenta. The method described was used for real-time monitoring of Rho123 concentrations in both the maternal and fetal compartments. Determination was processed by fluorescence detection (lambda(ex)=480 nm, lambda(em)580 nm); calibration curve was linear over the range 0.01-50 mumoll(-1) (r=0.99965), detection limit was 10 nmoll(-1) (3sigma) and RSD2% (10 readings). Transport of Rho123 was scanned under various conditions (ATP-synthesis inhibition) and several inhibitors of P-glycoprotein transporter were tested (e.g. quinidine). The advantages of the modern SIA method-an automated analytical tool providing both fast and precise analysis-were successfully demonstrated for examination of transport profiles to investigate the effect of P-glycoprotein on the placental transfer of Rho123.

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Extraction on the solid phase is a rapid, simple, effective, and flexible method of preparation of samples for the analysis proper and it can be used in many areas of analysis (pharmacy, biochemistry, food industry, environmental examination, etc.). Possible use in on-line and automatic systems is also advantageous. A very wide scale of proposed sorbents and the use of their combinations thus make extraction on the solid phase an effective method for the isolation and preconcentration of the analyte from the complex matrix of the sample.

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A flow injection-spectrophotometric determination at 540 nm of hydroxyamphetamine is reported. The procedure is based on a coloured reaction with 2-hydrazono-3-methylbenzothiazole (MBTH) and ceric ammonium nitrate (CeIV) as the oxidation reagent. Under optimised conditions, the determination of hydroxyamphetamine is achieved in a range of 0.01-0.2 mmol.l-1 with a relative standard deviation of 0.78% for 0.05 mmol.l-1 (n = 10) and a sample throughput of 75.h-1. The method was used for the determination of medicinal drug in the mass-produced dosage form of Czech origin: Pedrolon drops, Galena a.c.

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1. The transplacental transfer of D-xylose was investigated in the present study. 2. Umbilical perfusion of the rat term placenta was used to study materno-foetal (M-F) and foetomaternal (F-M) transfer of this compound. 3. D-Xylose was found to cross the rat term placenta very quickly in the M-F direction, with subsequent accumulation in the foetal compartment (the F-M ratio being 2.23 at the end of the experiments). In contrast, no transfer in the F-M direction was observed. 4. A possible facilitation of the transplacental transfer of D-xylose from the mother to foetus in rats is suggested.

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Urinary nitrate is known to be a measure of environmental exposure. Only recently an endogenous metabolic pathway resulting in nitrate synthesis was described. We have determined the concentration of nitrate expressed as nitrate/creatinine ratio in the urine of patients in whom a significant environmental nitrate load was presumed to be absent. A significant elevation of nitrates in patients with inflammatory bowel disease compared with patients with non-inflammatory disorders was observed (0.173 +/- 0.155 vs. 0.037 +/- 0.016 mol/mol creatinine, P < 0.01). Increased nitrate excretion in the urine of patients with inflammatory bowel disease may reflect the endogenous nitrate synthesis induced by the immune activation.

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It is very difficult to meet all prerequisites for the optimization of the tuberculostatic action of thiobenzamides. On the one hand, a strongly polarized C=S bond of the thiocarbamido group is necessary, and on the other hand, the value of the Hammett constant must be positive (to prevent hepatotoxicity). The conjugated system can be extended to reduce the excitation energy of the eta-eta electronic transition. However, the lipophilicity should not be overincreased (to avoid the risk of increased antimitotic activity and acute toxicity). Of the culture media, the Sauton system seems to be best suited since it is the most simple. However, the culture medium according to Sula comes closest to in vivo conditions as it contains proteins and is devoid of surfactants.

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