TY - CONF A1 - van Wasen, Sebastian A1 - Bierstedt, Andreas A1 - Volmer, D. A1 - Riedel, Jens T1 - Airborne laser-spark ion source for direct microfluidic coupling N2 - The development and improvement of new ionization techniques for mass spectrometry often requires dedicated, specific sampling approaches. Recently, a novel ionization scheme for ambient MS has been introduced based on a quasi-continuous laser-induced plasma, which was ignited directly before the MS inlet. This setup combines the general advantages of ambient ionization, provides electro neutrality, sufficient duty cycle and a ubiquitous plasma medium. A high repetition rate DPSS laser (Conqueror 3-LAMBDA, Nd:YVO4, 1 - 500 kHz, average output power: 12 W at 50 kHz, Compact Laser Solutions GmbH, Germany) and the corresponding optomechanical system were installed on an optical breadboard above the inlet of a LCQ DecaXP ion trap mass spectrometer. The quasi-continuous airborne plasma was ignited inside the sprayed sample in front of the inlet via focused laser irradiation. The introduction of liquid samples into laser-induced plasmas requires higher plasma power during solvent evaporation as compared to gaseous samples. This increased demand was approached via a two-fold strategy: Firstly, an alternative, more powerful, laser plasma driven by the fundamental instead of the second harmonic wavelength was implemented, which provided a 10-fold increase of signal intensity, while maintaining the same reagent ion pattern as the previous plasma. Protonated water clusters [(H2O]nH]+, NH4+ as well as charge transfer promoting ion O2+, dominated the reagent ion mass spectrum. Secondly, a miniaturized nebulizer was used to minimize the size of the plasma quenching solvent droplets. The result of these improvements was a new and very stable ion source for direct microfluidic coupling. A variety of samples demonstrated the performance of the ion source. A laser-driven plasma was shown to be a powerful ion source for gaseous and solid samples. For the first time, liquid samples were examined using the novel source. In addition to demonstrating an improved strategy for igniting the laser plasma, this contribution also covers the miniaturization of the spray source for enhanced ionization, while minimizing sample consumption via a microfluidic spray systems. T2 - International Mass Spectrometry Conference 2018 CY - Florence, Italy DA - 26.08.2018 KW - Airborne KW - Laser-spark KW - Laser-induced plasma KW - Microfluidic KW - Mass Spectrometry PY - 2018 AN - OPUS4-45839 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - van Wasen, Sebastian A1 - Bierstedt, Andreas A1 - Riedel, Jens T1 - Airborne laser-spark for ambient desorption/ionization of liquids N2 - The development and enhancement of new ionization techniques for mass spectrometry often needs to be custom-tailored for specific sampling approaches. Here, a direct sampling ionization technique is presented for ambient mass spectrometry. Ambient mass spectrometry based techniques are typically used to analyze samples in their native states without sample pretreatment. This new design is based on a quasi-continuous airborne plasma which is ignited inside the particulate air via a focused laser irradiation. Desorption and ionization of the analyte molecules are achieved by the laser plasma without reaching the plasma. The ionization process is induced by interaction with nascent ionic fragments, electrons and ultraviolet photons in the plasma vicinity. Previously, this method was solely used for the characterization of solid and gaseous analytes. The sample introduction was occurred via thermal desorption and headspace analysis. This study focuses on the potential applicability of liquid samples. In comparison to previous approaches, the usage of liquid samples has an impact on the stability of typically used plasma of 532 nm. It was necessary to realize an alternative plasma using light of the fundamental wavelength of 1064 nm. That new plasma resulted in a significant more stable and bright plasma and the first laser plasma ionization spectrum was recorded for an analyte in the condensed phase with a mass spectrometer of type LCQ DecaXP. T2 - European Mass Spectrometry Conference 2018 CY - Saarbrücken, Germany DA - 11.03.2018 KW - Laser-spark KW - Laser-induced plasma KW - Ambient mass spectrometry KW - Ambient desorption/ionization KW - DPSS laser PY - 2018 AN - OPUS4-44493 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -