REDUCTION OF MATRIX INTERFERENCES FOR LEAD DETERMINATION WITH THE LVOV PLATFORM AND THE GRAPHITE FURNACE

The addition to the graphite furnace of a thin pyrolytic graphite plate (L'vov Platform) on which the sample is deposited, makes it possible to atomize the sample at more nearly constant temperature conditions. This reduces analytical interferences that arise from a variation in the appearance temperature for Pb when it is present in different matrices. In addition, this platform makes it possible to volatilize the sample into a gas that is hotter than the surface from which the sample is volatilized. This reduces the interference re-suiting from the volatility of Pb halides. Using the platform, we can determine Pb in matrices which contain chloride, sulfate, phosphate without resorting to matrix modifications. It remains necessary to carbide-coat the platform surface to reduce its reactivity with Pb. © 1979, American Chemical Society. All rights reserved.