Refinements in the automated fluorometric histamine analysis system.

The automated continuous flow system for the extraction and fluorometric analysis of histamine has been further improved. Samples with or without protein can be analyzed. The use of a single pump, added nitrogen, and lower concentration of o-phthalaldehyde increase the sensitivity by 5-10 fold and allow the analysis of samples at the rate of 30 per hour. Samples which are less than 0.5 ml in volume and contain 0.1 to 10 ng/ml histamine can routinely be analyzed. The sensitivity of the system is now 0.05 ng and compares favorably with isotopic techniques.