US EPA

2148453 

Technical Report 

Microenvironment of Breast Tissue: Lithocholic Acid and Other Intestinal Steroids 

Javitt, NB 

1995 

NTIS/02982955_3 

GRA and I 

GRA and I 

Methods are in development for the analysis of bile acids in breast cyst fluid. For detection of bile acids at the femtomole level as a fluorescent ester linked through the 3-hydroxyl group common to most naturally-occurring bile acid, pyrene-l-carbonyl azide is under evaluation. Using known bile acid standards the fluorescent derivatives have been prepared under mild conditions and separated by reverse phase HPLC. However, decomposition of the azide and the instability of the isocyanate formed during the reaction gives a number of interfering fluorescent peaks. Fractionation of breast cyst fluid using a reverse phase C-18 cartridge provides an aliquot containing bile acids. However, unidentified fluorescent peaks also occur which may represent either artifacts or unidentified naturally-occurring compounds in breast cyst fluid. Resolution of the remaining analytical problems will permit analysis of 99 samples of breast fluid that have been obtained thus far.