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See Harris Ch. 28. Lecture 5 Sample preparation. Making a fine powder is often necessary before digestion of extraction. Sample digestion. All organic compounds are destroyed Toxic elements determined via atomic spectra. Harris Chapter 28. High-pressure digestion (microwave is possible!). - PowerPoint PPT Presentation
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Lecture 5Sample preparation
See Harris Ch. 28
Making a fine powder is often necessary before digestion of extraction
Sample digestion
All organic compounds are destroyedToxic elements determined via atomic spectra
Harris Chapter 28
High-pressure digestion (microwave is possible!)
Microwave digestionor extraction
Sampling
LiquidOptional protein precipitation
SolidOptional protein precipitation
Homogenize in buffer
Isolation-Single step liquid-liquid extraction- Multiple step liquid-liquid extraction- Solid phase extraction- (pre)concentration
DATA COLLECTION
Data processing and interpretation
Organic Compounds
Solvent extraction techniques
Filters:Can be also used for Solid Phase Extraction
Solid Phase Extraction cartridges
Solid Phase Extraction
Inside the SPE cartridge…
polar
non-polar
Various sorption techniques:
centrifuge
positive pressure
Large volumes:
SPE extraction:Lots of junk removed!
Microdiffusion (Conway) cell
Preconcentration of volatile compounds
A simple device for headspace LPME. Stirring and thermostating are optional.
A 1 mL drop at the end of a syringe needle.
Liqiud phase microextraction (LPME)