High performance aqueous compound isotope analysis No Sample Derivatisation The LiquiFace is designed to couple any standard high pressure liquid chromatograph (HPLC) or pumping system to the isoprime precisION IRMS for the determination of 813( values in organic compounds. Aqueous solutions, separated by the HPLC unit, are converted to gaseous phases in the LiquiFace and transferred to the IRMS. The LiquiFace can analyze a range of sample types including: carbohydrates, alcohols, organic acids, amino acids and peptides. LC-IRMS of non-polar compounds da not need to undergo complex derivatisations as with the same sample run via GC-IRMS. The removal of any need for derivatisation an these compounds means that back calculations da not need to be performed an the eventual 813( results. In many cases samples need only be diluted with pure water, filtered and then analyzed via LC-IRMS using the LiquiFace. HPLC or Direct lnjection Low Temperature Sample Conversion The LiquiFace can be connected to a HPLC unit and receive a sample liquid stream for conver sion to C02. Alternatively the internal pump an the Liquiface can be used to carry out direct injection of samples. Peristaltic pumps in the LiquiFace are used to deliver reagents to the reaction site and not the HPLC pump maximiz ing the users operational flexibility and choices. Direct injection to the LiquiFace means that users can perform both bulk isotopic analysis and compound-specific analysis using the same system. Conversion of the aqueous eluent to sample gas is performed in a low temperature reactor at up to 100° c. Low temperature conversion of the eluent allows our interface to analyze thermolabile sam ples which will disintegrate at elevated tempera tures. The mixture of eluent and sample gasses, generated in the LiquiFace heater are cooled to room temperature and then seperated in a gas exchanger with the remaining eluent going to a waste line and the sample gas passing through a Nation dryer into the isoprime precisION IRMS.

LiquiFace Exceptional Tolerance to Excess Oxygen When the LiquiFace is coupled to the isoprime precisION Isotope Ratio Mass Spectrometer, the result is an exceptional system with an unparalleled tolerance for excess oxygen load. With the use of sodium persulfate as oxidation agent, a large oxygen excess can enter the IRMS and damage the ionisation filament. The unique thorium coating of the isoprime precisION ionisation filament results in lifetimes of years rather than months. This resistance to oxygen means that an on-line reduction furnace to remove the excess is not required, reducing consumables...