Determination of Carbon, Hydrogen, Nitrogen and Sulphur content by weight

Combustion elemental microanalysis allows the quantitation, in a single experiment, of the contents of the main elements associated with life, i.e. carbon, hydrogen, nitrogen and sulfur. It can be carried out on most kinds of solid, liquid and viscous samples, and it has the additional advantages of being quick and inexpensive and requiring only 1 mg of material.

Main application fields:

1. Identity and purity of synthetic compounds
Combustion microanalysis is used to establish compound purity. It requires small amounts of sample, which is an advantage when studying scarce materials such as compounds synthesized at the research lab scale.

2. Analysis of pharmaceutical products
Because most excipients lack nitrogen, its quantitation allows the determination of active principle content in pharmaceutical dosage forms.

3. Analysis of materials
One example is the control of the process of surfactant removal during the synthesis of mesoporous silica nanoparticles.

4. Analysis of fuels
-Quality control: Quantitation of S and N as contaminant impurities.
-Direct determination of the H/C ratio in fuels.
-Calculation of the heat of combustion of fuels.

5. Agricultural and environmental analysis
-C and N content in soils.
-Determination of the C/N ratio in fertilizers.
-Micronutrient levels in plants, in particular S and N.

Other environmentally relevant studies:
-CHN quantitation in oceanographic filtrates.
-Paleoclimatic studies.

6. Food analysis.
Two examples:
-Nitrogen quantitation as an alternative to Kjeldahl’s wet digestion method.
-Sulfur content in distiller grains.