A novel highly selective sample cleanup procedure based on the use of molecularly imprinted polymers (MIPs) as solid-phase extraction materials has been evaluated with respect to its applicability and routine use in environmental analysis. The method comprises the combination of a restricted access material (RAM) and a MIP allowing a selective sample preparation to be achieved in the online mode. This combination is called the size-selective sample separation and solvent switch (six-SPE). The RAM column combines size exclusion and adsorption chromatography, reducing the concentration of matrix molecules by a cutoff of 15 kDa. The MIP column selectively retains the triazine analytes whereas the residual matrix is not retained and separated completely. Thus, the automated RAM-MIP is capable of excluding all matrix and nontarget compounds. The cleaned and enriched extract is subsequently eluted to an HPLC column and analyzed by LC-MS. A complete on-line analysis cycle including multidimensional solid-phase extraction, separation, and detection takes less than 15 min. Terbuthylazine, atrazine, propazine, simazine, ametryn, prometryn, irgarol, and also the metabolites deethylatrazine and deisopropylatrazine can be determined without any matrix interferences, e.g., by humic acids. The whole setup is fully automated and may be continuously operated. Nonspecific interactions with the polymer are below 1% in all cases. The accuracy of the LC-MIP-LC-MS system was controlled using a certified reference material (Aquacheck). The applicability of the method to the cleanup of real samples was demonstrated by injection of contaminated river water samples. The stability of different polymers was tested by consecutive injections, and it was shown that the performance of the materials did not vary even after more than 300 enrichment and desorption cycles.
Objectives: There is a risk of adverse health effects for personnel with occupational exposure to antineoplastic agents. The aim of the present longitudinal study was to identify, quantify, and evaluate potential health hazards of occupationally exposed workers in pharmaceutical and oncological departments with central processing units for drug preparation. Methods: One hundred operatives in 14 German hospital pharmacies and oncological departments underwent biological monitoring by providing urine samples up to four times over a period of 3 years. Results: All antineoplastic agents that were considered (cyclophosphamide, ifosfamide, doxorubicin, epirubicin and platinum from cisplatin and carboplatin), were found in urine samples in up to 40% of participants. Conclusions: Despite standard safety precautions, such as the use of vertical laminar air flow safety cabinets, and personal protective clothing, incorporation of drugs was detected. Therefore, an environmental monitoring strategy should be developed in order to detect contamination and attempt to improve hygiene during work.
A series of highly cross-linked terpolymers of methacryloylated cholesterol or bile acid
methyl esters, methacrylic acid, and ethyleneglycol dimethacrylate were prepared in the
presence or absence of cholesterol acting as a template molecule. The polymers were freed
from cholesterol by washing and the resulting adsorbents tested for cholesterol rebinding
in the chromatographic mode using methanol−water as mobile phase or in the batch mode
using an intestinal mimicking fluid of concentrated bile acids in water. The polymers
prepared in polar solvents, favoring the apolar association of the template and the apolar
face of the amphiphilic monomers, exhibited selective rebinding of cholesterol as compared
to a nonimprinted blank polymer prepared identically but without cholesterol. The strongest
rebinding was seen for the polymer prepared using 3β-methacryloyl-cholesterol as the
functional monomer. Using a physiologically relevant intestinal-mimicking solution of
cholesterol (1 mM), these polymers adsorbed ca. 17 mg cholesterol per gram dry adsorbent,
whereas a nonimprinted blank polymer adsorbed ca. 13 mg. The imprinted polymers showed
the highest uptake of cholesterol as compared to other adsorbents (<13 mg/g) that were
expected to show high affinity for cholesterol.
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