Ambient Desorption, Ionization, and Extraction Source for Mars Exploration

Trace Matters Scientific LLC proposes to design, develop, and prototype a miniature ambient desorption, ionization, and extraction source (MADIE) as a compact all-in-one instrument for operation under the ambient Martian environment to sequentially desorb, ionize, and extract analytes from Martian samples. The MADIE will enable in situ interrogation of the Martian mineralogical samples with no sample preparation and/or separation when coupled to a mass spectrometer. At the core of the proposed MADIE will be a self-tuning plasma ionization module for sample ionization, consisting of an ambient carbon dioxide plasma source and a tuning circuit; an ion funnel module for efficient ion extraction; and a laser diode module for time-resolved sample desorption. The ambient plasma source will utilize the Martian atmosphere, which is mainly composed of carbon dioxide, to form a reduced-pressure carbon dioxide inductively coupled plasma (ICP) to ionize the plume of sampled analytes. The tuning circuit will compensate any plasma variation and maintain the plasma source at resonance during operation. The ion funnel module, which will be derived by a radio frequency power supply, will efficiently extract the ions and guide them into the mass spectrometer to increase sensitivity. The laser diode module will produce a plume of sample analytes from the sample surface with high spatial resolution at both ultraviolet (UV) and infrared (IR) wavelengths. During phase I, the self-tuning plasma ionization module will be designed and constructed, and the ion funnel will be designed and simulated with SIMION and then prototyped. Commercially-available laser modules at various wavelengths will be selected and experimentally validated. These modules will then be pieced together to develop a breadboard prototype of the MADIE by the conclusion of phase I. Preliminary experiments will be conducted to test the efficiency of the MADIE.