Application of Stir Bar Sorptive Extraction (SBSE) Coupled to Thermal Desorption GC-MS for Determination of Ultra-Trace Level Compounds in Aqueous Samples

During the past decade, miniaturized and solvent-less sample preparation techniques based on sorptive extraction, e.g. solid phase micro-extraction (SPME), have proven to be simple, fast and environmentally friendly alternatives to LLE while maintaining or even improving sensitivity. In 1999, a new extraction technique known as stir bar sorptive extraction (SBSE) using stir bars coated with…

Elimination of Non-Volatile Sample Matrix Components After GC Injection using a Thermal Desorber and Microvial Inserts

GC analysis of complex sample types containing non-volatile materials normally requires extensive sample preparation and cleanup prior to injection to eliminate the interference from non-volatile components. Accumulation of nonvolatile matrix components in the inlet and at the head of the GC column can lead to generation of active sites, analyte degradation, poor quantitation due to…

Fast Screening of Apple Flavor Compounds using SPME in Combination with Fast Capillary GC-MS using a Modular Accelerated Column Heater (MACH) and Quadrupole Mass Spectrometric Detector (qMSD)

A fast HS-SPME-CGC-MSD method for the analysis of flavor compounds of apples was developed. A complete profile was obtained after solid phase micro-extraction within 3 minutes GC run-time using a modular accelerated column heater (MACH). Detection with a state-of-the-art quadrupole MSD allowed a data acquisition rate of 20 Hz, while the mass spectral data quality…

Evaluation of PDMS-Based Extraction Techniques and GC-TOFMS for the Analysis of Off-flavor Chemicals in Beer

Various techniques employing polydimethylsiloxane (PDMS) as an extraction medium prior to GC-TOFMS analysis were investigated to measure off-flavors in aged beer. The techniques included stir bar sorptive extraction (SBSE), headspace sorptive extraction (HSSE), purge-and-trap (P&T) and closed-loop-stripping (CLS). SBSE appeared to provide the most accurate quantitation and was capable of detecting the most odor-active compounds.…

Target GC-MS Analysis using Accelerated Column Heating and Interactive Deconvolution Software

In diverse fields ranging from environmental samples to complex flavor preparations, high performance, high resolution capillary gas chromatography/mass spectrometry, GC-MS, has become the preferred technique for identifying and quantifying target compounds at trace levels. Many of these samples are characterized by very complex matrices, which provide a substantial challenge for contemporary capillary GC-MS. This situation…

Headspace Sampling Unit Combined with a Metal Oxide Sensor or Standard Detectors for Quantification of VOC Emissions from Beverage Cans or Other Packaging Materials

The quality of packaging materials used in the food and beverage industry must be controlled regularly in order to avoid negative effects on packaged products caused by emissions, e.g. VOC emissions from printing processes or from varnishes used on inner surfaces of the packaging material. Many companies have worldwide production sites, that may not all…

Improving MS Detection of Malachite Green in Fish Products using Automated SPE coupled with an LC/Ion Trap MS system

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…

Improving MS Detection of Aflatoxins using Automated Solid Phase Extraction and Derivatization coupled with an LC/MS System

Aflatoxins are metabolites from molds such as Aspergillus flavus and Aspergillus Parasiticus. Afl atoxins are classified as mycotoxins, they are among the most potent human carcinogens, found mainly in foods and feed of plant origin. High concentrations of afl atoxins have been found, for example, in pistachios, figs and cereals and aflatoxins have also been…

Automated Dynamic Headspace Sampling of Aqueous Samples Using Replaceable Adsorbent Traps

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…

Automated Multi-Residue Pesticide Analysis in Fruits and Vegetables by Disposable Pipette Extraction (DPX) and Gas Chromatography/Mass Spectrometry

One of the most important aspects of reducing pesticide exposure is monitoring of pesticide residues in foods. A number of analytical methods have been developed, many of them based on traditional liquid-liquid extraction, gelpermeation or solid phase extraction in combination with GCMS or LC-MS. Recently, the QuEChERS (quick, easy, cheap, effective, rugged and safe) sample…

Simple, Fast and Reliable Determination of Fat in Food According to the Caviezel® Method using a Turnkey Fat Determination System

Fat determination is one of the key analyses performed in food industry and in public food monitoring programs in order to control production processes, to ensure accurate labelling, and to monitor food safety. Therefore, a fast and reliable procedure for routine determination of fat is in great demand. Using the Cavieziel® Method, based on the…

Determination of Trace Components Using a Selectable 1D/2D GC-MS System based on Capillary Flow Technology and Heart-Cut Fraction Collection

Identification of important trace components in complex samples like fragrances, natural products, petroleum fractions or polymers can be challenging. Achieving the mass on column and resolution necessary to locate and identify trace components using a single chromatographic separation can be difficult if not impossible. A selectable 1D/2D GC-MS confi guration using Agilent capillary fl ow…

Automated Static and Dynamic Headspace Analysis with GC-MS for Determination of Abundant and Trace Flavour Compounds in Alcoholic Beverages Containing Dry Extract

Direct injection for gas chromatographic profiling of alcoholic beverages is usually preferable, but where spirits and liquors contain appreciable amounts of non-volatile material, some mode of pre-treatment may be required to avoid both inlet and column contamination. This consideration applies in particular to products aged for extended periods in wooden barrels and especially products containing…