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The prevalence of osteoporosis in RA remains high in the modern era despite aggressive management and the use of biologic therapy. Most RA patients with osteoporosis can be identified by a simple algorithm taking age and BMI into account.

The performance of the fully automated membrane-assisted solvent extraction was investigated for 47 environmental contaminants (among them 30 organochlorine compounds, 9 organophosphorus compounds, and 7 triazines). The extraction took place in a 20-mL headspace vial filled with the aqueous sample and containing a polypropylene membrane bag with 1 mL of cyclohexane as extractant. This device was handled by a multipurpose sampler, which enabled the sample to be mixed at a defined temperature with subsequent large-volume injection of the organic extract taken out of the membrane bag. After optimization of extraction parameters, the method was validated for the three compound classes, triazines and organochlorine and organophosphorus compounds, using spiked distilled water. Then, the extraction yield of these analytes from several complex samples such as a natural and a synthetic wastewater, a bacterial culture, and orange juice was determined and compared to a conventional liquid-liquid extraction. Furthermore, the possibility of reducing matrix interference by adding salt, methanol, or detergent during membrane-assisted solvent extraction was investigated.

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Extraction of polycyclic aromatic hydrocarbons and organochlorine compounds from water: A comparison between solid-phase microextraction and stir bar sorptive extractionThe enrichment of semi-volatile compounds from water using solid-phase microextraction (SPME) and stir bar sorptive extraction (SBSE) was compared. The investigations (analysis of PAHs and organochlorine compounds) were performed to compare SPME-GC/MS and SBSE-thermodesorption-GC/MS. Additionally, SPME fibres and stir bars were desorbed in a small volume of solvent and analysed by HPLC with fluorescence detection. This method was applied to PAHs. SBSE is more robust and under the given conditions (extraction from a 10 mL sample, 1 h exposure time of fibres and stir bars) enables higher recoveries (20.1 -97.2%) for the compounds investigated than SPME (recoveries of 6.3 -51.6%). Detection limits between 0.1 and 4.5 ng/L were calculated for the SPME-GC/MS combination, whereas the SBSE-GC/ MS combination enabled detection limits between 0.05 and 1.0 ng/L. Coupled to HPLC, the detection limits of the PAHs investigated were found to range between 1.0 and 10.0 ng/L (SPME) or between 0.3 and 2.0 ng/L (SBSE). The advantage of SPME is that the procedure can be completely automated, which is not possible when combining SBSE with GC or LC.

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