Determination of Trace Alkali and Alkaline Earth Metals in Orange Juice Using the DC Plasma and the Inductively Coupled Plasma Atomic Emission Techniques

Matrix effects in plasma spectroscopy have been measured in a simulated biological substrate. The authors show comparisons of such effects using both inductively coupled and direct current plasmas. The matrix influences are much more pronounced in direct current plasmas, but are also present when dealing with alkali metals in inductively coupled plasmas as well. The latter finding represents a particularly significant finding because it points the way to a method of determining alkali metals at levels of parts per billion.