Dropless ESI for IMS at ambient conditions

The generation and extraction of the charged particles (ions, clusters) from a fluid in a strong electric field at ambient conditions using a dynamic liquid flow splitter on the meniscus was examined. The existence of non-droplets regimes for obtaining charged particles for liquid flow rates up to 1000 μL/min, solute concentrations up to 1 M and acid content in solution up to 1% was displayed. Depending on the experimental conditions a conventional fluid electrospraying regime at ambient conditions in air as well as a dropless regime were demonstrated for obtaining charged particles current. The performance of the ion mobility spectrometer with a Bradbury-Nielsen gate at a dropless mode of charged particles generation was demonstrated for solutions of Human serum albumin (69,367 Da), Apoferritin (445,000 Da) and human epidermoid carcinoma A431 cells. The concentration of each substance in the solutions was ranging from 10 −4 to 10 −5 M. The concentration of cells in the suspension was 1 million/mL.