In terms of comparisons with ESI, the internal energy distributions obtained with the four DBD-based ion source presented above . The normalized internal energies obtained for DBDI, LTP, FµTP and ACaPI are respectively 185%, 172%, 192% and 117% of those in ESI. Parameters such as the distance between the DBD plasma jet and the source, as well as the capillary nature, strongly influence the ion fragmentation yields. The largest effect came from the positioning of the plasma device: placing the device on-axis resulted in a decrease of internal energy for DBDI, LTP, and FµTP to ~160% of that in ESI.