Determination of pharmaceuticals in wastewaters using solid-phase extraction-liquid chromatography-tandem mass spectrometry

10.1002/jssc.201101002Four different commercial sorbents for solid-phase extraction have been evaluated for the extraction of a group of acidic pharmaceuticals in terms of selectivity and capacity: Oasis hydrophilic-lipophilic balance (HLB), Oasis MAX (strong anion exchange), Oasis WAX (weak anion exchange) and a commercial available molecularly imprinted polymer specific for non-steroidal anti-inflammatory drugs. Among the sorbents studied, molecularly imprinted polymer proved to be very effective in the reduction of matrix interferences and the selective extraction of acidic pharmaceuticals, such as salicylic acid, ibuprofen, fenoprofen, diclofenac and naproxen, among others, from effluent wastewater samples. Moreover, molecularly imprinted solid-phase extraction protocol was applied to liquid chromatography coupled to tandem mass spectrometry (MS/MS) with the purpose of evaluating the clean-up effect on ion suppression/enhancement when the complexity of the samples increases and a reduction of this effect was observed. Molecularly imprinted solid-phase extraction followed by liquid chromatography coupled to ultraviolet detection and liquid chromatography coupled to tandem mass spectrometry validation methodologies with effluent wastewaters were developed, obtaining recoveries between 70 and 85% and limits of detection at low levels of µg/L (0.15-1 µg/L) and ng/L (0.5-2 ng/L), respectively. The final application of molecularly imprinted solid-phase extraction and liquid chromatography coupled to MS/MS detection showed the presence of acidic pharmaceuticals studied in this work in effluent wastewaters

A rapid determination of acidic pharmaceuticals in environmental waters by molecularly imprinted solid-phase extraction coupled to tandem mass spectrometry without chromatography

10.1016/j.talanta.2013.02.03

Novel coatings for stir bar sorptive extraction to determine pharmaceuticals and personal care products in environmental waters by liquid chromatography and tandem mass spectrometry

10.1016/j.aca.2013.03.010Two new commercially available polar coatings for stir bar sorptive extraction (SBSE), consisting of polyacrylate (PA) with a proportion of polyethyleneglycol (PEG) (Acrylate Twister®) and PEG modified silicone (EG Silicone Twister®), were evaluated and compared with the classic coating based on polydimethylsiloxane (PDMS Twister®) for the extraction of a group of pharmaceuticals and personal care products (PPCPs) from wastewater samples. The SBSE parameters, such as sample pH, agitation speed, extraction temperature, extraction time, desorption solvent and time, were optimised in order to achieve suitable sorption of the target analytes. The EG Silicone coating enabled more efficient extraction of some polar compounds as well as improving the sorption of apolar compounds, in comparison with the other two coatings. Finally, the method of SBSE followed by liquid chromatography coupled to tandem mass spectrometry (LC¿MS/MS) using the EG Silicone coating was validated achieving good linearity (r2 > 0.994, except for CBZ (r2 > 0.989)), precision (%RSD < 17%) and low limits of quantification (LOQs) (20¿40 ng L-1). The SBSE/LC¿MS/MS methodology was applied for the determination of PPCPs in wastewater samples

Preparation of a polar monolithic coating for stir bar sorptive extraction of emerging contaminants from wastewaters

A new polar monolith based on poly(poly(ethylene glycol) methacrylate-co-pentaerythritol triacrylate) (poly(PEGMA-co-PETRA)) was first synthesised, after the optimisation of the polymerisation conditions, and applied as a coating for the stir bar sorptive extraction (SBSE) of a group of pharmaceuticals and personal care products (PPCPs) from environmental water samples.Several parameters affecting extraction and liquid desorption in SBSE were investigated to achieve the optimal sorption efficiencies for the studied analytes. Under the optimised experimental conditions, a rapid, simple and sensitive SBSE performance was provided by the in-house monolithic stir bar. Moreover, the in-house coating was able to extract and desorb most of the studied analytes more effectively and quickly, due to its polar behaviour and suitable mechanical and physical properties, in comparison with the recently commercialised polar stir bars (EG Silicone Twister® and Acrylate Twister®).The analytical methodology, including SBSE followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), was validated and successfully applied for the determination of a group of PPCPs in wastewater samples