Improved Flame AA Sensitivities Using a Titanium Ultrasonic Nebulizer

Abstract

Nebulization and desolvation are essential steps in flame AA processes before sample atomization. It is possible to improve atomization efficiency and sensitivities by improving the nebulization and desolvation efficiencies. Previous studies using an aluminum ultrasonic nebulizer (operated at 78.0 KHz) for interfacing HPLC and flame AA showed better sensitivity than typical commercial pneumatical concentric nebulizers (1). However, it was found that the aluminum ultrasonic nebulizer gave unreproducible performance due to chemical corrosion on the nebulizing surface. A titanium ultrasonic nebulizer (operated at 57.7 KHz) was used to overcome the corrosion problem. The titanium ultrasonic nebulizer with the help of a desolvation device provided reproducible performance and showed improved sensitivities compared with data obtained by using a simple pneumatic concentric nebulizer but less than that using an aluminum nebulizer^(1). Studies showed that further improvement on flame AA sensitivity is possible by using a higher ultrasonic drive frequency and stronger desolvation process.