Abstract: This paper describes the measurement of tryptophane with synchronized scan fluorescent spectroscopy in maize, wheat and pollen. In general, am-ino acids are determined with an amino acid analyzer or HPLC. But the tryptophane is destroyed in acidolysis. Another sample has to be prepared. It is very inconvenient. Fortunately, the tryptophane has the highest natural fluorescent intensity. It provides an advantage for direct determination of trp. The sample is treated with 4N NaOH for 24h at 105℃. The pH value is adjusted to 10.5-11,0, and the sample is diluted to volume before determining trp. with △λ68nm for synchronous scanning. The fluorescent intensity is in linear correlation with the concentration of trp. in the test range of 0.01-0.20μg/ml.

Key words: Fluorescent spectroscopy, Tryptophane