A short lecture about Atomic Spectroscopy: Flame Photometry, Atomic Absorption, and Atomic Emission with Coupled Plasma (FP, AA and ICP-AES). Presented at 28.03.2011, Faculty of Agriculture, Hebrew University of Jerusalem, by Vasiliy Rosen, M.Sc.

1. Atomic Spectroscopy: Basic Principles And Instruments Vasiliy V. Rosen, M.Sc., ZBM Analytical Laboratory www.rosen.r8.org 2011

2. Atomic Spectroscopy Absorption Spectroscopy: AAS Emission Spectroscopy: FES, ICP-AES(OES) Mass Spectrometry

3. Atomic Spectroscopy Ion Emission Atom Emission E – energy difference between two levels; h – Plank’s constant, 6.626068 × 10-34 m2kg/s; c – speed of light, 299 792 458 m/s; λ – wavelenght, nm After Boss. C.B. and Freden K.J. Concepts, Instrumentation and Techniques in Inductively Coupled Plasma Optical Emission Spectrometry. 1997

4. Atomic Spectroscopy Nebulizer converts the solution into a spray Flame (or Plasma) causes the solvent to evaporate, leaving dry aerosol particles, then volatilizes the particles, producing atomic, molecular and ionic species After Skoog D. Fundamentals of Analytical Chemistry, 2004, p. 844

6. Optical filter is used to monitor for the selected emission wavelength produced by the analyte;

9. Atomic absorption spectrometry quantifies the absorption of ground state atoms in the gaseous state ;

12. Atomic cell – flame (gas mixture) or graphite furnance (accepts solutions, slurries, or even solids).

13. Detector – photomultiplier.After G.Ma and G.W. Gonzales, http://www.cee.vt.edu

14. Atomic absorption spectroscopy (AAS)

15. Atomicemissionspectroscopy ICP-AES Inductively Coupled Plasma - Atomic Emission Spectrometry

17. Inductively Coupled Plasma spectrometers use emission spectroscopy to detect and quantify elements in a sample;

18. ICP-AES uses the argon plasma (6000-10000º C) for atomization and excitation of the sample atoms;

20. ICP-aes spectrometer arcos

21. Schematic diagram of the processes in the ICP After SpectroGmbh, Germany

23. Plasma: to generate the signal. Plasma is forming in the torch from gas argon.

24. Optics: to measure the signal.

26. ICP-AES: Plasma Inductively Coupled Plasma Source A plasma is a hot, partially ionized gas. It contains relatively high concentrations of ions and electrons. Argon ions, once formed in a plasma, are capable of absorbing sufficient power from an external source to maintain the temperature at a level at which further ionization sustains the plasma indefinitely. The plasma temperature is about 10 000 K. After Manning T.J. and Grow W.P., 1997

27. ICP-AES: Plasma Inductively Coupled Plasma Source

29. alkali metals (Na, K, Li) calibration is more linear;

30. less spectral interferences;

31. lower sensitivity (Limit-of-Detection is higher);

32. more suitable for light matrices;

33. alkali metals (Na, K, Li) calibration is less linear;

34. more spectral interferences;

36. ICP-AES: optics After SpectroGmbh, Germany

37. ICP-AES: Sample Preparation Microwave-assisted Digestion Hot Plate Digestion Block Most samples have to be prepared for analysis by ICP. Solid samples are solubilized. Organic matter is "mineralized" i.e. converted to inorganic compounds.

38. ICP-AES: calibration curve

39. ICP-AES: spectral interferences Au (gold) peak on 242.795 nm

40. ICP-AES: spectral interferences Au (gold) peak on 242.795 nm is interfered by Mn 242.794 nm Au (gold) peak on 267.595 nm is free of Mn interference!

42. Environmental Analysis: trace metals and other elements in waters, soils, plants, composts and sludges;

43. Pharmaceuticals: traces of catalysts used; traces of poison metals (Cd, Pb etc);

44. Industry: trace metal analysis in raw materials; noble metals determination.

45. Forensic science: gunshot powder residue analysis, toxicological examination ( e.g., thallium (Tl) determination)

47. Skoog, D. Fundamentals of Analytical Chemistry, 2004

48. Ma, G. and Gonzales, G.B. Flame Atomic Absorption Spectrometry. http://www.cee.vt.edu

49. Manning T.J. and Grow W.P. Inductively Coupled Plasma Atomic Emission Spectrometry. The Chemical Educator, v.1. N 2. 1997.

50. Lecture by Dr. MordechayShoenfeld, “ICP-AES”, Course 71106, Faculty of Agriculture, HUJI. 2010.