Page 129 - Applied Pharmacognosy

Types of Chemical markers

• Flame-ionization detectors (FID):These are the most widely used

detectors.

• Thermal conductivity detectors (TCD):These are UNIVERSAL

detectors but of moderate sensitivity.

• Electron-capture detectors (ECD):These are highly specific for

halogenated compounds such as pesticides.

• Mass Spectrometer (GC/MS): The GC separates the compounds from

each other, while the mass spectrometer helps to identify them based
on their
fragmentation pattern