Post in Bubble forming at the tip of SS emitter for nano ESI: ABRF Discussion Forum: ABRF Discussion Forums

Dear Emanuele, Usually when we see the droplet forming at the nano columns/emitters's tip is due to air in the system or the waste line T connection, You can flush air, use column and pre-column equilibration script to get rid of the air faster than isocratic mode, or disconnect the waste line tubing from T connector while pumping nano flow and then connect it again, if you have salt deposit buildup on the tip, you can sonicate the tip 40 sec in 100% methanol,40 sec in 100% isopropanol and 40 sec in 100% HPLC grade water and try again, you can also play with spray voltage to get the spray stable( go as low as 1.4 and then go up 0.1 at the time, watch the spray current to see the improvement and spray stability, you can also monitor the 391 m/z for spray stability, don't get the tip closer than recommended to the source. Hope these tips helps to resolve the bubble/druplet issues you have, Regards, Khatereh Motamedchaboki, PhD. Director, Proteomics Facility Sanford Burnham Prebys Medical Discovery Institute 10901 North Torrey Pines Road La Jolla, CA 92037 Tel: (858) 646 3100 Ext: 3710 Fax: (858) 795 5221 http://www.sbpdiscovery.org/technology/sr/Pages/LaJolla_Proteomics.aspx