A novel stir bar sorptive extraction (SBSE) procedure termed sequential SBSE was developed. Compared to conventional SBSE, sequential SBSE provides more uniform enrichment over the entire polarity/volatility range for organic pollutants at ultra-trace levels in water. Sequential SBSE consists of a SBSE performed sequentially on a 5-mL sample first without modifier using one stir bar, then on the same sample after addition of 30 % NaCl using a second stir bar.

Static (equilibrium) headspace sampling is commonly used for GC determination of volatiles in solid and liquid samples. Since this technique relies on the analyte partitioning between the sample and headspace and uses a fixed injection volume it may not provide adequate detection limits, particularly for higher molecular weight, higher boiling analytes, and for polar analytes in aqueous samples.

Fatty acids are of key importance to the food industry. Especially long chain polyunsaturated fatty acids (LC PUFA) are receiving more and more attention due to their positive influence on human health. LC PUFA refined from natural oils are frequently added to food products to gain a positive health effect. Since LC PUFA are rather unstable and prone to oxidation, the quality of oils and fats has to be controlled. Certain aldehydes, ketones and other compounds are markers for oil and fat quality. Some of these have unpleasant odors and/or tastes (e.g. fishy) which are not acceptable to consumers.

A method for characterization of airborne particles including the nanoparticles fraction with a diameter of 29-58 nm in roadside atmosphere has been described. The method consists of thermal extraction (TE) and comprehensive two-dimensional gas chromatography (GC x GC) with novel detection capabilities, including high resolution time-of-flight mass spectrometry (HRTOF-MS), and simultaneous selective and mass spectrometric detection with a nitrogen phosphorous detector (NPD) and a quadrupole mass spectrometer (qMS). Increased selectivity with the GC x GC - HRTOF-MS allows a group type separation of a selected chemical class, e.g.

Aflatoxins are metabolites from molds such as Aspergillus flavus and Aspergillus Parasiticus. Aflatoxins are classified as mycotoxins, they are among the most potent human carcinogens, found mainly in foods and feed of plant origin. High concentrations of aflatoxins have been found, for example, in pistachios, figs and cereals and aflatoxins have also been found in dairy products. Due to the high toxicity of aflatoxins, EU legislation specifies very low acceptable daily intakes and maximum residue limits (0.05-15 μg/kg).

Malachite green (MG) is a triphenyl methane dye that is highly efficient in battling fungi, bacteria and various single cell parasites. MG is traditionally used in aquaculture to treat and prevent fungal infections. MG, which is structurally related to known carcinogenic triphenylmethane dyes, is metabolized to leucomalachite green (LMG) and deposited in the fatty tissue of the fish. MG is under suspicion of being a human carcinogen and for causing damage to the human genetic material.

Solid phase microextraction (SPME) is a powerful technique for the analysis of trace components in a wide variety of matrices. The types of compounds which can be analyzed by this technique ranges from non-polar to semi-polar materials due to the different fiber materials available. Most applications favor headspace over immersion sampling, therefore the analytes must be volatile enough to partition into the headspace of the vial being sampled. Often, heating and agitation of the sample are required. Quantification can be a challenge due to matrix effects. Automation of these and other steps can help with sample throughput, precision and accuracy.

Solid Phase Extraction (SPE) using standard cartridges is widely regarded as the method of choice to extract analytes from samples with complex matrices or to extract and concentrate analytes from a wide variety of samples in general. In this paper, an automated SPE system is presented that is based on standard cartridges. It is shown that SPE with standard cartridges is easily and efficiently automated for use in LC/MS-based determination of illegal antibiotics in food products of animal origin. An established manual SPE method was easily transferred to the GERSTEL MultiPurpose Sampler (MPS) using the SPE option under MAESTRO software control.

A multi-residue method for determination of five groups of 85 pesticides - organochlorine, carbamate, organophosphorous, pyrethroid and others - in non-fatty food, e.g. vegetables, fruits and green tea is described. The method is based on stir bar sorptive extraction (SBSE) coupled to thermal desorption (TD) and retention time locked (RTL) GC-MS in the scan mode. Samples are extracted with methanol and diluted with water prior to SBSE. Dilution of the methanol extract before SBSE was optimized to obtain high sensitivity, and to minimize sample matrix effects (particularly for the pesticides with high log Ko/w values).

A multi-residue method to determine five groups of 85 pesticides - chlorinated, carbamate, phosphorous, pyrethroid and others - in vegetables, fruits and green tea has been developed using stir bar sorptive extraction (SBSE) coupled to thermal desorption and retention time locked (RTL) GC-MS. Pre-extraction with methanol and dilution with water prior to SBSE (60 min) were performed. Dilution of methanol extract for SBSE was examined to obtain high sensitivity and to compensate the effect of adsorption to the glass wall of extraction vessel and to sample matrix for the compounds with high log Ko/w values (e.g. pyrethroid).