Page 85 - Illustrated Pocket Dictionary of Chromatography

FLAME-IONIZATION DETECTOR (FID) 81

filter, syringe Attaches to the end of a syringe and is used to
remove particulates from samples. Filter syringes are one-time use
filters. They come in a wide range of materials (e.g., cellulose, glass,
nitrocellulose, PTFE) to make them compatible with a wide range of
solvents and solutions. They come in a wide range of diameters and
pore sizes. Correct selection of composition, diameter, and pore size
is important for overall performance and reproducibility.

Syringe filters of different diameters and pore sizes. The most common filter pore
diameters are 0.45 and 0.2mm. Note that the top filter is 0.02mm. Construction of
the housing is typically polypropylene or polyethylene, and all these are connected
to a syringe via a Luer port.

fixed-wavelength detector Utilizes a lamp that emits a fixed
wavelength lamp such as cadmium (l= 229nm), zinc (l= 214nm),
mercury (l= 313, 340, 365, 405, 426, 546nm), and deuterium (l= 214,
229, 254, 280, 313, 340, 365nm). Filters are used to prevent unwanted
wavelengths through the system.
flame-ionization detector (FID) A destructive mass flow
detector used in GC analyses. The sample is burned in the detector,
and the current generated by the sample combustion generates the
signal. For hydrocarbon compounds, the FID signal is approximately
proportional to the number of carbons in the sample. The linear range