Flow injection-flame atomic FAAS

Notes HG-AAS, Aydride generation atomic absorption spectrometry HG-AFS, /tydride generation atomic fluorescence spectrometry FI-CV-AAS, flow-injection cold-vapor atomic absorption spectrometry FAAS,flame atomic absorption spectrometry GF-AAS, graphite furnace atomic absorption spectrometry and ET-AAS, electrothermal atomic absorption spectrometry. 

Belal et al [40] reported on the use of flame atomic absorption spectroscopy (FAAS), coupled with ion-exchange, to determine EDTA in dosage forms. EDTA is complexed with either Ca(II) or Mg(II) at pH 10, and the excess cations retained on an ion-exchange resin. At the same time, the Ca(II) or Mg(III) EDTA complexes are eluted and determined by AAS. Calibration curves were found to be linear over the range of 4-160 and 2-32 pg/mL EDTA when using Ca(II) or Mg(II), respectively. The method could be applied to eye drops and ampoules containing pharmaceuticals. Another combined AAS flow injection system was proposed for the determination of EDTA based on its reaction with Cu(II). The calibration curve was linear over the range of 5-50 pg/mL, with a limit of detection of 0.1 pg/mL [41]. 

FI. flow injection SI, sequential injection ICP-AES, inductively coupled plasma-atomic emission spectrometry FAAS, flame atomic absorption spectrometry, ETAAS electrothermal atomic absorption spectrometry, ICP-MS inductively coupled plasma-mass spectrometry, HG-AAS hydrige generation-atomic absorption spectrometry, HG-AFS hydrige generation-atomic fluorescence spectrometry. 

The next logical step in improving micro FAAS procedures was to use discrete sample injections into a flowing carrier liquid being pumped into the nebulizer of a flame atomic... 

Atomic spectrometric techniques such as flame atomic absorption spectrometry (FAAS), electrothermal AAS (ETAAS), inductively coupled plasma atomic emission spectrometry (ICP-AES), and ICP-MS are used for the determination of elements, particularly metals. ICP-MS is the most sensitive, typically with microgram per liter detection limits and multielement capability but it has high start-up and operating costs. UV-visible spectrophotometry is also used for the determination of metal ions and anions such as nitrate and phosphate (usually by selective deriva-tization). It is a low cost and straightforward technique, and portable (handheld) instruments are available for field deployment. Flow injection (FI) provides a highly reproducible means of manipulating solution chemistry in a contamination free environment, and is often used for sample manipulation, e.g., derivatization, dilution, preconcentration and matrix removal, in conjunction with spectrometric detection. Electroanalytical techniques, particularly voltammetry and ion-selective electrodes (ISEs), are... 

Note BA biamperometric titration CE-CCD capillary electrophoresis with contactless conductivity detection CL chemiluminescence EB electrochemical biosensor FAAS flame atomic absorption spectrometry FIA flow injection analysis HPLC-UV high-performance liquid chromatography with UV detection MC multicommutation P potentiometry SIA sequential injection analysis SP spectrophotometry TB turbidimetry. 

A low-temperature flame is used to prevent the excitation of most other metals Wide dynamic range with online dilution and/ or preconcentration steps Flow rate in the flow system should be carefully selected and compared with the aspiration rate of the nebulizer Sample spends short time in contact with nebulizer and burner, so that the measuring system is readily rinsed between consecutive injections High sample throughput High tolerance to saline matrices Better adapted to SIA technique Improved sensitivity with regard to FAAS due to the rapid atomization of the entire sample... 

---