Second derivative-high-performance liquid chromatographic-fluorometric detection of porphyrins in chick embryo liver cell culture medium.

A high-performance liquid chromatographic system is described which is suitable for the separation and quantitative determination of a mixture of porphyrin esters in nanogram quantities from the culture medium used for maintenance of a monolayer culture of chick embryo liver cells. The desired sensitivity was obtained by coupling a high-performance liquid chromatograph with a second derivative-fluorometric detection system. The most effective method for preparation of the porphyrin methyl esters prior to chromatography was found to be lyophilization of the culture medium prior to esterification with 5% sulphuric acid in methanol.