The principle of the EIM-IRMS® method is based on the dehydration of ethanol using an EIM catalyst, specially developed by SG Isotech, followed by pyrolysis of gas and measurement of the relative ratio of Hydrogenstable isotopes in the Hydrogen gas created.
The missing link in Isotope Analysis
We have developed, certified, and patented a new isotope method for analysis of wine, grape must, fruit juices, alcoholic beverages, and honey – Ethanol Isotope Measurement – Isotope Ratio Mass Spectrometry (EIM-IRMS®).EIM-IRMS® method is capable of providing unique molecular fingerprint that cannot be reproduced or counterfeited. It is used to determine production practices used in wine and honey production, and product authentication for the purpose of protecting producers and consumers.
EIM-IRMS® is significantly more precise, sample analysis is shorter, and the equipment used, Isotope Ratio Mass Spectrometry (IRMS) is much more readily available and cheaper than equipment for nuclear magnetic resonance (NMR) method, which can only be used for wine with known geographical origin.
Instrument Description
The EIMPyro can be connected over the Open Split interface to any standard Isotope Ratio MS.
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Helium: 99.9999% purity
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230V, 50/60 Hz
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770 x 470 x 460 (w x d x h)
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75 kg (net value)
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Can be connected to AS3000, AI 1310 Liquid Autosampleror GC Pal Autosamplers for liquid samples with 2 injection ports
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"EIM Calculator" software for calculation of final results
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Base unit EIMPyro (two furnaces) with temperature control display
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Software regulation of temperature and Helium flow
All products containing ethanol or fermentable sugars can be prepared for analysis by the EIM-IRMS method and equipment. As the abbreviation EIM itself suggests, it is an Ethanol Isotope Measurement concept, so the main analyte under test is Ethanol. Fermentable sugars must first be converted to Ethanol, which is analyzed for the botanical origin of the starting material used in production.
The alcoholic strength of the wine distillate should be greater than 92% vol.
From 30 to 40 samples can be analyzed within a single sequence.
Analytical kits for each type of product being tested are available for purchase. These kits contain everything needed for the analysis and can be purchased from SG Isotech. One kit is sufficient for the analysis of 100 to 400 samples depending on the kit purchased.
EIMPyro uses AI1310 Liquid Autosampler peripheral, but will also work with AS3000 or GC Pal Autosamplers for liquid samples.
When performing analysis, 3-5 injections or each sample should be done.
SG Isotech has developed software called “EIM9000” which is used for calculation of dDn results. It comes as a standard package with EIM-Pyro. It also calculates average dDn value and SD for each analyzed sample.
After connecting the EIM-Pyro peripherals to the isotope ratio MS and after raising the temperature in the reactors, it is necessary to determine whether all the connections are leak-free before starting the sequence. By switching the mass on the middle detector to 40 (Argon) it is necessary to monitor the background which should be below 40 mV. Leak checking must be performed before each analysis begins. If the leakage is higher, it is necessary to check all connections. As a rule start from the closest connection to the furthest connection from IRMS.
The NMR concept is based on the technique of counting deuterium atoms on a methyl and methylene group of ethanol, which oscillate at appropriate frequencies in a strong magnetic field. EIM technique is based on determining the dD values of non-exchangeable stable isotopes of Hydrogen in ethanol. The analytical values obtained by both techniques are very precise, but there is a difference in the natural ranges of these analytical parameters for ethanol with a different botanical origin, and accordingly a difference in the level of detection of illegal production practices in the production of wine, fruit juices, alcoholic beverages, and honey. For NMR this difference for ethanol with the different botanical origin is only 1 ppm, while for EIM it is about 50 ‰ on a relative scale, making EIM method a lot more precise.
The accuracy of measurement is expressed by the precision limits of the repeatability and reproducibility which can be calculated from the sample standard deviation of the results. The repeatability precision limit (r) and the reproducibility precision limit (R) for EIM-IRMS are calculated as follows:
r = 2.8 × sr = 2.7‰ ;
R = 2.8 × sR = 2.13 ‰
Where:
- sR - Interlaboratory Reproducibility standard deviation as Standard deviation of all measurements of the same sample expressed in ‰
- sr − Interlaboratory Repeatability standard deviation as the average standard deviation for the same sample expressed in ‰
The analysis of one sample takes 5-8 minutes.
Yes, there is no problem to analyze ethanol samples from different sources.
Ethanol is firstly quantitatively dehydrated without isotopic fractionation over specifically designed EIM Catalyst and then pyrolyzed and elemental Hydrogen gas is obtained.
If by any chance a distillate of less than 92% vol is obtained, the distillation process of the sample should be repeated and the alcoholic strength and recovery determined again.
EIM-Pyro peripheral automatically controls the temperature of the reactors. There is no need to manually raise or lower the temperature, but this option also exists.
Approximately 3-4 hours.
EIM-Pyro works under standard room temperature conditions, just like the IRMS it is connected to. Recommended room temperature is 15°C to 25°C.
EIMPyro for Isotope Ratio Mass Spectrometry
EIM-IRMS® (Ethanol Isotope Measurement – Isotope Ratio Mass Spectrometry) revolutionized measurement of relative ratio of non-exchangeable Hydrogen stable isotopes (D/H)n (δDn) in ethanol previously quantitatively extracted from wine, fruit juice, strong spirit or fermented honey samples).
This technology has become the integral part of EIMPyro® peripheral for Isotope Ratio MS. EIMPyro® provides rapid and quantitative intramolecular dehydration of ethanol sample over custom made EIM-catalyst prior to high precision isotope ratio measurement during a single analysis. Perypheral provides precise values and quicker analysis times and precisions are attained on sub-microliter amounts of ethanol with analytical time of 8-10 minutes.
How EIMPyro® works
- Because of ethanol’s hydroxyl group, which includes exchangeable Hydrogen atom, ethanol δD value obtained only by Pyrolysis Conversion Elemental Analyzer or peripheral is not a reliable and repeatable analytical parameter.
- EIMPyro® Peripheral solves this problem and gives high precision, repeatable and reproducible results by obtaining isotope ratio of non-exchangeable (D/H)n in ethanol sample during a single analysis.
- EIMPyro® Peripheral can be coupled to any standard and conventional Isotope Ratio MS which has the option of measuring Hydrogen stable isotopes.
Acknowledgements
EIM-IRMS®method has been validated through interlaboratory testing between three laboratories:
- Imprint Analytics, Neutal (Austria)
Validation Report - IzotoptechZrt. at MTA AtomkiInstitute for Nuclear Research of the HAS Hungarian Academy of Science, Debrecen (Hungary)
Validation Report - C.N.R.I.F.F.I. -China National Research Institute of Food and Fermentation Industries Corporation Limited, Beijing (People’s Republic of China)
Validation Report - Research Laboratory of Food Quality & Technology (PNIL) of the Scientific Research & Education Center of the People's Friendship University of Russia (RUDN University) THE INTRA-LABORATORY STUDY OF EIM-IRMS METHOD PERFORMANCE WITH CS-qNMR ( CUMULATIVE SCREENING - quantitative NMR)
SG Isotech also thanks Prof. Jed P. Sparks, Kimberly L. Sparks and Cornell University Stable Isotope Laboratory (COIL), NY, United States, for cooperation and providing more online EIM–Module-IRMS®results
Why Choose EIMPyro® Module
EIMPyro peripheral which is developed and designed on SG Isotech's patented "know-how" is a universal instrument that replaces 5 other very expensive individual instruments used for stable isotope testing. To learn more go to the "Technology" page.