Elimination of boron memory effect in inductively coupled plasma-mass spectrometry by ammonia gas injection into the spray chamber during analysis

Injection of 10-20 ml/min of ammonia gas into an inductively coupled plasma -mass spectrometry (ICP-MS) spray chamber during boron determination elimin ates the memory effect of a 1 mu g/ml B solution within a 2-min washing tim e. Ammonia gas injection also reduces the boron blank by a factor of four a nd enhances the sensitivity by 33-90%. Boron detection limits are improved from 12 and 14 to 3 and 4 ng/ml, respectively, for mio ICP-MS instruments. Trace boron concentrations in certified reference materials agree well usin g ammonia gas injection. (C) 2000 Elsevier Science B.V. All rights reserved .