In metabolomics studies, large sample sets have to be analyzed to allow statistical differentiation of sample types. Obviously, repeatability of the whole analytical workflow, including sample preparation, sample introduction, separation and detection, is extremely important in order to achieve such a differentiation. Automating the sample preparation workflow is a very useful first step towards reducing analytical variability.

Liquid-liquid extractions have long been performed manually and are used to extract and concentrate analytes from aqueous matrices. Inclusion of liquid-liquid extraction ...

This application note describes the direct thermal desorption of desirable and undesirable aroma compounds from edible oils. The oil sample is placed in a microvial from where it is directly thermally desorbed using a GERSTEL Thermal Desorption Unit (TDU). Volatile compounds are transferred to the GC/MS system while leaving the non-volatile oil matrix behind in the microvial, preventing it from reaching and contaminating the GC inlet and the GC column. Different designs of microvials were evaluated for effectiveness of analyte transfer.

This note presents a fully automated analysis system for the determination of Δ9-tetrahydrocannabinol (THC) and its metabolites in blood serum. Automation is based ...

Analyzing blood serum for opioids, cocaine and metabolites is a routine task in forensic laboratories. The most commonly used methods involve several manual or ...

Pyrolysis GC-MS was used to profile residual solids after drying aged whiskey samples. The samples in question were both 20 years old from the same unaged parent distillate but matured in the very different wood species of Quercus Robur and Quercus Alba.

In order to improve pyrolysis chromatographic analysis of materials that release polar functional groups e.g. carboxylic acids, a simple and rapid methylation method based on TDU-pyrolysis/GC-MS in the presence of tetramethylammonium hydroxide (TMAH) was developed. Linseed oil was selected as test material because of its high triglyceride content comprising both saturated and unsaturated fatty acids. Pyrolysis was performed at 500, 600 and 700 °C using a GERSTEL pyrolysis module (PYRO) with a heated platinum filament.

The US Consumer Product Safety Commission’s (CPSC) Test Method CPSC-CH-C1001-09.3 [1], is used by testing laboratories for the determination of phthalate content in children’s toys and child care articles covered by the standard set forth in the Consumer Product Safety Improvement Act Section 108. The CPSC determined that an appropriate combination of methods of extraction and analysis is sufficient to determine the concentration of the six regulated phthalates in most consumer products.

Modern capillary GC injection generally uses the universal dual mode split/splitless injection port or inlet in which the pneumatic mode is selected at the outset. The inlet is maintained at a sufficiently high set temperature to allow instant vaporization of the sample after deposition in the inlet liner (usually 4mm i.d.) Of course this explosive vaporization is associated with the well documented undesirable phenomenon of needle discrimination. If analytes are in aqueous solution another effect is induced by the very high saturated vapor volume of water compared to other solvents. A 1 μL injection of water in hot splitless mode will give a vapor volume greater than the retaining capacity of the liner and can inhibit the subsequent vaporization of analytes.

This study shows the use of the GERSTEL MPS 2/TDU/CIS with pyrolysis module for generating simulated thermal gravimetric-mass spectrometry data (TGA-MS) of ...