Exeter Analytical has released data that demonstrates the capability of its model 440 micro analyser for determination of the percentage of CHN in heterogeneous soil, plant and insect samples.
Traditional methodologies for determining carbon (C), hydrogen (H) and nitrogen (N) content of soil, plant and insect samples typically use macro-CHN or Kjehldahl Nitrogen analysis.
While both these techniques are proven to generate useful data, both have drawbacks.
Macro-CHN analysers are relatively expensive to purchase and run compared with micro-CHN systems and Kjehldahl requires use of highly corrosive and toxic chemicals.
Using an Exeter Analytical model 440 SCRI has accurately and precisely determined the CHN content of a range of soil, plant and insect materials using samples sizes of typically 2-20mg.
Gill Banks of SCRI said: 'With our plant and soil materials the excellent detector response linearity of the model 440 has proven to be important as composition can vary within a batch of samples.
'To cope with our often slowly combusting samples the model 440 usefully offers provision for flexible combustion times and oxygen flows.
'Using the combustion optimisation software has enabled us to test a sample under various conditions in a single run to identify the optimum analytical conditions.'
She added: 'As soil, plant and insect samples often have high levels of inorganics - combustion generates large sample residues.
'Using a horizontal sample injection system, our Exeter Analytical model 440 automatically removes sample residue after each analysis thereby avoiding memory effects, gas flow problems and considerably extending the number of samples we can run between changing combustion tubes.
'Beneficially removing the residue also eliminates problems associated with accelerated degradation of the quartz combustion tubes due to levels of sodium often found in soil and plant samples.'
Designed to give accurate, reliable results over the widest range of sample types presented for analysis, the model 440 CHN micro analyser is proven to deliver operating accuracy and precision.
Low gas and reagent consumption combined with higher reduction tube life allows the model 440 to deliver low operating costs.
The model 440 is a fully automated analyser.
Intuitive Windows-based operating software reduces human errors through incorporation of automation, customer help and diagnostic facilities.
