IRMS laboratory
The Isotope Ratio Mass Spectrometry (IRMS) laboratory provides analyses of light stable isotopes as a service offered mainly to researchers in Plant Physiology but in many other biological applications too. We have been active since 1993 and can offer a wide range of analytical services.
Presently, we have a mass spectrometer manufactured by GV-Instruments coupled with three alternatives interfaces. This instrument is of the continuous flow type, which provide rapid, precise, and accurate measurements. The sensitivity of this mass spectrometer allows analysis of submilligram amounts of the element (e.g. C, N or S).
1- EA-IRMS
The IRMS instrument is interfaced to an elemental analyser for combustion and analysis of solid samples (or liquid for very low quantity). The isotopes ratios 13C/12C ; 15N/14N or 34S/32S can be determined in soil and plant sample materials with a precision in the delta value of about 0,15 ‰ (standard deviation for repeated samples) for carbon (minimum 20µg C), 0,2 ‰ for nitrogen (minimum 15µg N) or 0,5 ‰ for sulphur (minimum 10µg S).
A diluter allows sequential analysis of N and C from organic molecules where the N/C ratio is small (typically 1/10, measurements are possible up to 1/100).
2- Microgas-IRMS
Module for preparation of gaseous samples. The 13C/12C of carbon dioxide in air can be determined with a precision in the delta value of about 0,3 ‰ (350 ppm CO2 in 10ml air).
3- GC-IRMS (in training)
With this instrument, organic compounds can firstly be separated using a gas chromatography (GC) and thereafter analysed individually for the isotopes 13C or 15N after combustion.
Our routine analytical services are listed below.
Special prices can be offered to INRA team.
Analysis
Sample type
Sample size
Method
15N
Solid samples
8-120 µg Nitrogen
EA-CF
13C
Solid samples
10-1000 µg Carbon
EA-CF
15N/13C
Solid samples
Idem above
EA-CF
34S
Solid samples
2-50 µg Sulfur
EA-CF
13C
Atmospheric CO2
12 ml air
Microgas-CF
For information about the samples preparation and the delay, please contact:
marie-paule.bataille@unicaen.frIf interpretation of the data are necessary in addition to the isotope ratio value, contact Lab Manager for details:
alain.ourry@unicaen.frQuality assurance
Internal Standards are pure gases (N2, CO2 or SO2) calibrated with standards IAEA.