Direct introduction of solid samples is possible with Analytik Jena's ContrAA 700 and Zeenit series of atomic absorption spectrophotometers, available in the UK from Lambda Advanced Technology
With both manual and automatic sampling systems available, this unique sample handling method brings major benefits.
These include: analysis of unadulterated original samples, no time- consuming sample digestion, analysis of difficult to dissolve samples and volatile samples, no dilution effect with substances harmful to health or the environment, minimized risk of contamination, high sensitivity, genuine microvolume sampling (sample volumes in the order of and#956;g or mg) and detection limits in the pg and fg ranges.
These combine to bring speed, reduced costs, flexibility and efficiency.
Direct solids handling is made possible by the transversely heated graphite furnace design used in these instruments which gives constant heating along the entire length of the tube and also allows liquid samples to be introduced.
A specially optimised sample holder enables the analysis of various solids from powders to sample pieces.
The geometry of the holder guarantees the ideal atomisation conditions in the solids tube and reliable transport procedures for sample introduction.
The SSA 60 manual solid sampling system is easy to install and will accommodate a single sample.
The sample is weighed out onto the sample holder before transfer into the furnace.
The sample holder is made from the same graphite material as the graphite tubes and has a sample capacity of 30ul or approximately 50mg.
The SSA 600 fully automatic solid sampling system features 40 sample positions.
It also has a fully integrated micro balance to allow the correct amount of sample to be used.
A variety of operating modes are available through software control.
Direct solid sampling handling offers detection limits comparable to those obtainable with ICP MS.
It provides a fast screening method for unknown samples and is especially useful when only small sample quantities are available.
It is an excellent method for trace analysis and for complex solid samples which are difficult to digest or dissolve (e.g oxides, carbides, coal, cement) or for samples which are already finely powdered.
It is also well suited for homogeneity studies (characterization of certified reference materials).
