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Rosemary (Rosmarinus officinalis), garden sage (Salvia officinalis), summer savory (Satureja hortensis), laurel (Laurus nobilis), and other aromatic plants were put in olive oil and exposed to ultrasounds for different duration. Filtrated oils were dissolved in cyclohexane, and UV-Vis measurements were carried out. Absorbance values corresponding to chlorophylls, carotenoids, flavonoids (370 nm), and polyphenols (around 300 nm) were measured. In addition, for some samples, total phenols were determined using Folin-Denis reagent and compared with the similar maceration procedure in water solvent (instead of olive oil). Maceration without ultrasound in olive oil for each plant was also compared with ultrasound-assisted extraction. The results show that significant amount of aromatic content can be extracted in olive oil by applying ultrasounds for only few minutes, especially for Salvia officinalis powder. The use of UV-Vis measurements is simple but enough to examine the extent of phenol content extraction through such maceration procedure.

The development of a quantitative in-line Raman spectroscopic method for the monitoring of the active pharmaceutical ingredient, omeprazole synthesis reaction, and characterization of the reaction components is described. In-line monitoring was performed both with Fourier transform and dispersive Raman spectrometers. Prior to reaction monitoring, the reaction components were characterized off-line by means of Raman and NMR spectroscopy, both in solution and in solid state. To unequivocally confirm the presence of each component in the reaction mixture, a state of the art LC-SPE/NMR methodology was also used. Owing to its higher sensitivity, dispersive Raman spectroscopy was further employed for quantification purposes. The spectroscopic measurements and the complementary HPLC analyses, used in the calibration development, were gathered from a set of experiments, performed at a 1 L scale. On the basis of the data set obtained from the calibration experiments, a predictive partial least-squares (PLS) regression model was developed for all three reaction components, enabling an accurate determination of the percentage of each component present in the reaction mixture, at any time after the point when 25% of the starting material has been consumed. The model was successfully used to monitor the reaction progress in a kilo-lab scale experiment and can further be used as a fast response analytical tool in process optimization. It also has the potential to be used as part of a feedback control loop in the production plant.

Beta-blockers are chiral compounds with enantiomers that have different bioactivity, which means that while one is active, the other can be inactive or even harmful. Due to their high consumption and incomplete degradation in waste water, they may reach surface waters and affect aquatic organisms. To address this issue we developed a chromatographic method suitable for determining beta-blocker enantiomers in surface waters. It was tested on five beta-blockers (acebutolol, atenolol, bisoprolol, labetalol and metoprolol) and validated on bisoprolol enantiomers. Good enantioseparation of all analysed beta-blockers was achieved on the Chirobiotic V column with the mobile phase composed of methanol/acetic acid/triethylamine (100/0.20/0.15 v/v/v) at a flow rate of 0.5 mL/min and column temperature of 45 °C. Method proved to be linear in the concentration range from 0.075 µg/mL to 5 µg/mL, and showed good recovery. The limits of bisoprolol enantiomer detection were 0.025 µg/mL and 0.026 µg/mL and of quantification 0.075 µg/mL and 0.075 µg/mL. Despite its limitations, it seems to be a promising method for bisoprolol enantiomer analysis in surface water samples. Further research could focus on waste water analysis, where enantiomer concentrations may be high. Furthermore, transferring the method to a more sensitive one such as liquid chromatography coupled with tandem mass spectrometry and using ammonium acetate as the mobile phase additive instead of acetic acid and triethylamine would perhaps yield much lower limits of detection and quantification.

Identification of unknown pharmaceutical impurities is an essential part in the drug development process. In the present study, we developed and applied liquid chromatography (LC)-solid-phase extraction (SPE) / nuclear magnetic resonance (NMR) methodology with cryoprobe for identification and structural characterization of unknown impurities in 3-bromo-5-(trifluoromethyl)aniline. The three main impurities were separated and isolated by LC-SPE system. After multiple trapping, isolated impurities were eluted from the SPE cartridges with deuterated acetonitrile and one-and two-dimensional homo-and heteronuclear NMR spectra were recorded. The structures of the unknown impurities were determined by detailed inspection of NMR spectra and by mass spectrometric (MS) analysis. The results of the present preliminary study demonstrated that LC-SPE/NMR can be used for rapid impurity profiling of 3-bromo-5-(trifluoromethyl)aniline.