The ionisation may be chemical ionisation, the apparatus including means for heating the test sample, the calibration compounds being volatile in the heating means.

The field testing carried out varies greatly, e.g. pesticide residues, GMOs, chemical ionisation, prohibited ingredients (additives, processing aids), purity, heavy metals, dioxins, PAHs, mycotoxins, etc.

APCI” for atmospheric pressure chemical ionization,

Chemical ionization (CI) [1] [2] is a complementary method of electron ionization (IE).

This ionization process is generally referred to as Atmospheric Pressure Chemical Ionization (APCI).

Chemical ionization at atmospheric pressure (APCI) [4] [5] is a complementary method to electrospray.

Plasma-assisted reaction chemical ionization (PARCI) provides highly sensitive elemental analysis by producing positively and negatively charged ions.

This technique has been found to give much enchanced inonization for some substances, as compared to atmospheric pressure chemical ionization.

Ions generated were measured after negative chemical ionization.

The apparatus is configured to ionize the analyte molecules optionally via electrospray or chemical ionization.

The atoms/molecules are ionized, preferably by chemical ionization, and accumulated in the ion trap (410).

There are several ionization methods: electron impact, chemical ionization, electrospray, fast atom bombardment, matrix assisted laser desorption ionization, and others.