Microwave induced plasma optical emission spectrometry in agricultural analysis

The article describes the use of the recently commercially available technique of microwave induced plasma optical emission spectrometry with plasma gas (nitrogen) generation for the determination of calcium, magnesium, phosphorus and potassium in Mehlich 3 extracts. The specifics of the analysis of the agricultural samples for soil fertility assessment mean there are often a great number of samples to analyse in laboratory (the daily throughput of 500 or more samples). The analytical procedures were adapted to special requirements by the use of the new multielemental instrumental techniques. The detection limits were 0.43; 0.86; 0.20 and 0.06 mg/L; the precision for real sample analysis: 4.6; 1.0; 1.8 and 1.0%; the mean accuracy 97; 92; 107 and 100% for P, Ca, Mg and K, respectively, the real throughput reached 100 samples per hour.