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What is DART? DART stands for "Direct Analysis in Real Time" This is a revolutionary new ionization technique for rapid non-contact analysis of samples without any sample preparation. DART is operating at ambient pressure at the ground potential and gives, together with a high resolution (R=6000) Time Of Flight instrument an almost instant composition of the sample. click on the picture for a brochure in pdf-format. To view option for DART from IonSense click on DART and options, LC/MS or GC/MS to the left
What can be analyzed ? click on the pictures for application notes in pdf-format


More applications Everything on the picture to the right is analyzed without any pre-treatment. click on the picture to the right for Jeol's application notebook. Other applications of interest: - product control different types of basil - buried information in LC MS data different types of tea - polymerers nylon, polystyrene och cellulose - rubber tires

How does DART work ? An electrical discharge creates a plasma as inert gas flows through the DART chamber. The plasma contains ions, electrons, and excited neutral atoms and molecules. Electrostatic lenses in the DART remove ions and electrons, leaving only long-lived electronically or vibronically excited atoms and molecules (metasables). A grid at the exit of the DART source prevents ion-electron recombination and acts as an electron source for negative-ion formation. A heater coil increases the temperature of the gas as it travels towards the exit orifice of the source. An insulator cap ensures that no exposure to high voltage occurs outside the plasma chamber. The heated gas containing neutral but highly energetic atoms and molecules exits the source heading towards the inlet of the atmospheric pressure ionization mass spectrometer. The ions produced in the vapor phases between the DART insulator cap and mass spectrometer inlet are formed by interaction of the electronic excited-state species of helium or neon or vibronic excited-state species of nitrogen with the sample. The heated gas also assists in desorption of molecules on the surface of materials placed along the path between the cap and inlet. When He is used, the dominant positive-ion formation mechanism involves the formation of ionized water clusters followed by proton transfer reactions. read the scientific article by clicking on the picture
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Chemalys 2008-08-11