AAS Spectrophotometers: eadout mplifie Ebert monochromator Lamp me (a) Fig9-13(a) Signal at one wavelength often contains luminescence from interferents in flame Chemical interference: (i)reverses atomization equilibria (ii)reacts with analyte to form low volatility compound releasing agent-cations that react preferentially with interferent-Sr acts as releasing agent for Ca with phosphate protecting agent-form stable but volatile compounds with analyte(metal-EDTA formation constants) CEM 333 page 9.9 AAS Spectrophotometers: Fig 9-13(a) Signal at one wavelength often contains luminescence from interferents in flame Chemical interference: (i) reverses atomization equilibria (ii) reacts with analyte to form low volatility compound releasing agent - cations that react preferentially with interferent - Sr acts as releasing agent for Ca with phosphate protecting agent - form stable but volatile compounds with analyte (metal-EDTA formation constants) CEM 333 page 9.9