>Dear all, > >In adittion to Tullis question, can anyone suggest methods to improve >sensitivity (reduced sample amount demands) on my GCCIRMS compared to >the "standard performance"? I have a Delta plus connected to a GCC. > > Lars Löfgren Dear Lars, first you may try to concentrate your sample in a V glass vial, then dilute it in a minimum of solvent (30ul). Second, purification of the sample e.g. by TLC could reduce the noise thus improving signal/noise ratios. Third, you may try to increase the GC resolution (lower temperature rate, longer column, optimizing He flow, thinner phase thickness, ultrastable 100% methylsiloxane phase, true on column injector...) again to reduce noise level. Good luck, Eric LICHTFOUSE Laboratoire Sols et Environnement INRA-ENSAIA/INPL, BP 172 2, avenue de la foret de Haye F-54505 Vandoeuvre-les-Nancy Cedex, France Phone (33) 3 83 59 58 99 (-58 45, -58 65) Fax (33) 3 83 59 57 91 [log in to unmask]