A comparison of nebulizers for microbore LC-ICP-MS with mobile phases containing methanol

A comparison was made between a glass concentric nebulizer, a microconcentr ic nebulizer (MCN), and a Micro Mist nebulizer for the introduction of mobi le phases containing varying concentrations of methanol. For all nebulizers investigated, the signal remains constant with increasing sample flow rate at methanol concentrations greater than 20% of the mobile phase, even thou gh the rate that sample reaches the plasma increases at increasing flow rat es. A separation of tributlytin chloride (TBT) and triphenyltin chloride (T PhT) on a microbore reversed-phase HPLC column using a mobile phase consist ing of 70% methanol, 29% water, 1% glacial acetic acid and 4 mM ion pair re agent was investigated. At a flow rate of 0.2 ml min(-1), the absolute dete ction limits for the MCN were slightly higher than those obtained with the Micro Mist nebulizer or the glass concentric nebulizer. Precision and the l inearity of the calibration curves were comparable for all three nebulizers .