Elemental Analysis Service

Elemental Analysis is a technique that allows the simultaneous quantitative determination of carbon (C), hydrogen (H), nitrogen (N), and sulfur (S) in a wide variety of compounds, including organic, inorganic, organometallic substances, soils, materials, and more. This analytical technique complements other structural analysis methods for confirming the molecular formula of a compound, and it also serves as a criterion of purity.

The technique is based on the complete combustion of the sample at high temperatures in an oxygen-rich atmosphere. The sample is burned at 1050 °C in a combustion furnace, resulting in its total oxidation, such that combustion converts carbon into CO₂, hydrogen into H₂O, nitrogen into NOₓ, and sulfur into SO₂. The combustion gases are transported from the furnace, through scrubbing reagents, to infrared (IR) cells specific for CO₂, H₂O, and SO₂, enabling simultaneous and interference-free measurement. These gases are then removed, and NOₓ is reduced to N₂, with nitrogen being measured by non-specific thermal conductivity.

The Elemental Analysis Service at the Chemical Research Institute has the following equipment:

• LECO CHNS-TruSpec Elemental Analyser
• Sartorius M2P Microbalance, resolution of 0.1 µg and weighing range up to 2g

• The analyses will be carried out exclusively by the technical staff of the Elemental Analysis Service.
• Samples must be delivered to the Elemental Analysis Service. They must be clearly and indelibly labeled with a reference that must match the one indicated on the service request form.
• A service request form must be completed for each sample.
• It is recommended to submit the sample in a glass vial or, alternatively, in an Eppendorf tube to facilitate handling, in a minimum amount of 5 mg.
• Samples to be analyzed must be completely dry to avoid errors due to the presence of solvents or moisture.
• Samples may be in solid, gel, or liquid state and should be as homogeneous as possible. In the case of solid samples, they must be finely ground or crushed to facilitate combustion.
• The analysis of each sample will be performed in duplicate. If, due to the nature of the sample, two significantly different results are obtained, the technical staff will decide whether to perform a third analysis, which will entail an additional cost.
• When the sample is unstable, it is necessary to contact the technical staff of the Service to establish appropriate analysis conditions.
• The analysis results will be delivered by email in PDF format.
• Analyzed samples will be kept in the laboratory for a maximum period of one month, provided their return has been requested in the service request form. After this period, the samples will be disposed of.

Current rates for Scientific and Technical Services

Users can request the service by completing the following form or via the QR code.

For any questions, you can contact the responsible staff via email at