Powerful Analytics based on Modern Spectrometers

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1 Powerful Analytics based on Modern Spectrometers Gerhard Schlemmer Analytik Jena AG, Konrad- Zuse- Str. 1, Jena 1 1

2 Powerful Analytics based on Modern Spectrometers Optimizing Analytical Quality Absorption: Line oder Spectrum? Atomic Fluorescence: simple optics, excellent S/N: Where are the limits? Absorption/ Emission Sequential or simultaneous? Bio Analytics Limitations and chances due to new materials 2 2

Atomic Fluorescence: simple optics, excellent S/N: Where are the limits?

3 Analyt. Parameter System Component Influences Sensitivity Noise RSD Detection Limit Long Term Stability 3 Atomizer, Meas.Volume, Optics, Source Detector, Optics, Source, Elektronics Atomizer, Meas.Volume, Corrections (Detektor, Optics) Detector, Optics, Source, Elektronics Corrections, Sampel presentation Detector, Optics, Source, Elektronic, Correktions, Sample presentation DL RSD Working range. DL, RSD Working range. Repeatability Time for Measurement Range of Use Recovery; Calibration 3

Volume, Corrections (Detektor, Optics) Detector, Optics, Source, Elektronics Corrections, Sampel presentation Detector,

4 Absorption:Line oder Spectrum? Line Source AAS Optics Czerny- Turner Monochromator Resolution~ 200 pm 4 Double Echelle- Monochromator Resolution ~ 2 pm Based on DEMON ISAS-Berlin 4

5 Absorption:Line oder Spectrum? LS AAS Source Intensity Mn Triplet: 279, 4817 nm 279, 8269 nm 280, 1085 nm CS AAS Absorption spectra Mn Triplet: 279, 4817 nm 279, 8269 nm 280, 1085 nm Absorption 1, 0 0, 7 0, 5 0, 2 5 0, , , , , , , , , , , , 3 W e l le n lä n g e ( n m ) 5

Absorption spectra Mn Triplet: 279, 4817 nm 279, 8269 nm 280, 1085 nm Absorption 1, 0

6 Absorption: Linie oder Spektrum? LS Spectral window 200 pm Emission line ~2 pm Absorption profile 1-5 pm CS... CCD-Array with a resolution of ~ 2pm/ pixel 6 Spectral window 200 pm 6

7 Absorption: Line oder Spectrum? Is a source line really one line?: Emission of a Cd- hollow cathode lamp as a function of the lamp current. Ref. T. Labatzke, Analytik- Jena, C. Scholz, D. Mory, LTB, Berlin

8 Absorption: Line oder Spectrum? Corrections required in AAS source of error correction LS-AAS correction HR-CS- AAS source drift thermal emission unspecific absorption optical double beam sequential lamp modulation sequential BG correction, sequential (D2 lamp, Zeeman effekt, line reverse method) reference pixels simultaneous reference pixels simultaneous reference pixels Reference spektra simultaneous 8 8

thermal emission unspecific absorption optical double beam sequential lamp modulation sequential BG

9 HR-CSAAS A New Way to look at Atomic Absorbance Example: complex Background close to the analyte line NO- Structure in the vicinity of 213,857 nm 9 9

10 HR-CSAAS A New Way to look at Atomic Absorbance Determination of P on PO- Band at 246,400 nm using the C 2 H 2 / Air Flame (Absorbance reading on molecular Band) 10 10

11 HR-CSAAS A New Way to look at Atomic Absorbance Gain in information: absorbance becomes 3. dimensional Abs. wave length spectra 2D 11 Abs. wave length spectra 3D 11

12 Absorption: Line or Spectrum? Extended application range: atomic+molecular Simultaneous corrections for better accuracy Much more information on background Atomic lines Molecular band and fine structure Pushing the limits in complex matrices Independence of c 0 /m 0 on lamp type, age or fine structur Opening a new chapter on the way towards absolute analysis Will we finally approach real simultaneous AAS? 12 12

information on background Atomic lines Molecular band and fine structure Pushing the limits in complex

13 System Mercur Duo fluorescence and absorption in one system; measurement of mercury vapour in an argon carrier stream Atomic Fluorescence 0,03 Signalvergleich AFS / AAS 0,03 Intensität [ Ints ] 0,02 0,02 0,01 0,01 AFS-Signal 1µg/L AAS-Signal 1µg/L 0,025 0,02 0,015 0,01 0,005 0 Extiktion [ Ext ] 0,00-0, Integrationszeit [ sec. ] 13 13

Intensität [ Ints ] 0,02 0,02 0,01 0,01 AFS-Signal 1µg/L AAS-Signal 1µg/L 0,025 0,02 0,015

14 AAS vers.afs Parameter Application DL Lin. Calib. range Interferences AFS CVG only 0.3 ng/l (Hg) 10 4 Source drift Background Abs. Quenching AAS All techniques 3 ng/l (Hg) 10 2,5 Background Abs

15 Simultaneous vers. Sequential Reading ICP- OES Parameter Speed p. sample Speed p. element Working range DL Interferences Ruggedness Content of info ICP- Sequential ICP- Simult Cost

16 Simultaneous vers. Sequential ReadingUV/VIS Parameter Spectra Lin.Calib.Range Stray light Optical resolution Sample Ruggedness S/N Simultaneous (S600) Very fast <<1s ~2A 0.9%T*/0.05%T** 1-2 nm Full illumination Fixed optics + Sequential (S250) Slow 1 min ~3A 0.3%T*/0.005%T 0.5 nm Selected WL Moving parts * Validation at 198 nm; ** Validation at 220 nm 16

17 Bio Analytics Limitations and chances due to new applications Chips/cells/ flow system require photons and detection on a spot Direct contact with bio- media may require biocompatible materials Often extrem cost sensitive parts (disposables) Use of lightwave guides- Use of fiber- optic sensors

bio- media may require biocompatible materials Often extrem cost sensitive

18 Bio Analytics just a few examples of light wave guides/ fiber-optical sensors 18 18

19 Gesellschaft Deutscher Chemiker Fachgruppe Analytische Chemie Deutscher Arbeitskreis Spektroskopie DASp: Doktorandentreffen Jena, 9-10 Juli

20 ESAS 2008 Weimar, Sept 28th-Oct 1st The European Spectroscopy Symposium

Modern approaches to determination of toxic metals in marine environmental objects. Atomic absorption and inductively coupled plasma, advantages and

Modern approaches to determination of toxic metals in marine environmental objects. Atomic absorption and inductively coupled plasma, advantages and disadvantages Atomic spectroscopy Atomic spectroscopy