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The ability to effectively focus and transmit ions from relatively high pressure ion sources is a key factor that affects sensitivity and dynamic range in mass spectrometry. To improve upon the mass spectrometric sensitivity achievable with electrospray ionization sources a novel ion funnel interface has been developed and implemented with a triple quadrupole mass spectrometer. The ion funnel effectively consists of a series of ring electrodes of progressively smaller internal diamter to which RF and DC electric fields are co‐applied. The electric fields create a pseudo‐potential causing the collisionally damped ions to be more effectively focused and transmitted as a collimated ion beam. The ion funnel concept we describe is supported by results of SIMION simulations, ion current measurements and implementation with a mass spectrometer. Electrospray ionization mass spectra for an initial ion funnel configuration …