Knowledge Centre

There are a variety of libraries available for different applications. SCION Instruments offers various libraries including NIST, Wiley and Pfleger/Maurer/Weber (PMW) with customisable libraries and the ability to automatically search in multiple libraries. The most commonly used library is NIST. For the purpose of this technical note, NIST will be used as the example but the principles off all libraries

When setting out to analyze a sample from a complex sample matrix such as soil it is important to understand what analytes you are targeting and how to prepare your sample so it is suitable for your analysis. A common scope for analysis is to determine the quantity of semi volatile organics (SVOCs) in soil samples by gas chromatography (GC).

Volatile organic compounds (VOCs) are organic compounds which volatilize at lower temperatures e.g. limonene, ethanol and formaldehyde. Semi-volatile organic compounds (SVOCs) are organic compounds which tend to be solid or liquid at lower temperatures e.g. pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). SVOCs and VOCs are compounds commonly tested for and monitored by the analysis of environmental samples

The SCION Instruments Split/Splitless (SSL/ 1177) injector is designed to operate in two modes; split and splitless. This can be programmed in the instrument method. A split/splitless program allows customers to work with a wide range of sample concentrations. Within CompassCDS, you can easily switch between the two modes based on the concentration of the samples.

Headspace analysis is a sample preparation technique which can be used to extract volatile organic compounds (VOCs) from both solid and liquid sample matrices. Headspace is an extremely useful technique for analyzing VOCs with minimal sample preparation. Other extraction techniques may be needed for more complex sample matrices in which the EPA offers guidance.

Pipettes are an essential tool in laboratories which are used to transfer volumes of liquid from one vessel to another. They can be made from glass or plastic and can be manual or electronic. Following these best practice techniques this will lead to reliable results which you can be confident in.

Headspace is a versatile technique which allows for the analysis of volatile analytes in sample matrices which may be unsuitable to be directly injected into a GC or will require complicated sample preparation to make suitable. Sample preparation can be time consuming, require large volumes of expensive solvents and may introduce contamination into your sample.

QuEChERS is an acronym which stands for Quick, Easy, Cheap, Effective, Rugged and Safe. It is a very popular sample SPE (solid phase extraction) preparation technique which can be used for a number of sample matrices and analytes for example analysis of residual pesticides in fruits and vegetables. QuEChERS are a highly efficient, cost effective and versatile technique which can

Pulsed Flame Photometric Detector (PFPD), has a photomultiplier which looks at a flame within the detector. The signal is acquired from changes in colour of the flame. Each element has its own emission wavelength or colour (fluorescence). Band Pass Optical Filters are used to control which element is measured by filtering out light from other sources. The light from elemental

The Electron Capture Detector (ECD) was invented by James Lovelock and specifically designed to detect electrophilic compounds. The detector captures electrons from a radioactive source when electronegative analytes pass through. This gives high sensitivity, in the picogram range, for halogenated and other electron absorbing compounds.