CHEMICAL MODIFICATION FOR INDUCTIVELY-COUPLED PLASMA-ATOMIC EMISSION SPECTROMETRIC DETERMINATION OF BORON WITH TUNGSTEN BOAT FURNACE VAPORIZER

For electrothermal sample introduction, a commercially available tungs ten boat atomizer for atomic absorption spectrometry was transformed i nto a vaporizer for inductively coupled plasma atomic emission spectro metry. By placing a small amount of sodium hydroxide-diammonium hydrog enphosphate solution in the boat as chemical modifier prior to analysi s, the loss of boron which would occur during the drying and ashing st ages was suppressed. With this method, an enhancement in boron sensiti vity and no interference from foreign ions were observed. The detectio n limit (3sigma) was 0.1 ng ml-1 of boron. The relative standard devia tion for ten replicate determinations was 2.8% for 5 ng ml-1 of boron. The calibration graph was linear in the tested range of up to 1 mug m l-1 of boron. Analytical results for some steel alloy samples are pres ented.