Statistical Reexamination of Some Interference Patterns in the Determination of Calcium in Wheat (Triticum) by Atomic Absorption Spectrophotometry in an Air/Acetylene Flame

Abstract

The paper aims to statistically reexamine some interfereces that appear in the analysis of calcium by flame atomic absorption spectrophotometry in wheat (Triticum) sample, in the first vegetation stage.

The statistical study shows that in the air/acetylene flame for ourtype of samples the interference due to phosphorus is not significant (r²=0.19). A strong significant interference is due to the presence of Kjeldahl -, and nitrate-nitrogen in the original sample (R²=0.7869).

A multiple regression equation was calculated which allows the estimation of the masked amount of calcium, which makes un necessary the addition of a releasing agent, or the use of the N₂O-C₂H₂ flame for the elimination of interferences.

Key Words:

• flame atomic absorption spectrometry;
• calcium
• interference patterns
• statistics
• wheat