Solid matrix, room temperature phosphorescence identification and quantitation of the tetrahydrotetrols derived from the acid hydrolysis of benzo[a]pyrene-DNA adducts from human lung.

A new method, suitable for human biomonitoring, that uses room temperature phosphorescence for the detection of DNA damage by carcinogenic metabolites of polycyclic aromatic hydrocarbons is described. Samples of human lung DNA (1 mg) that had been subjected to immunoaffinity chromatography (anti-benzo[a]pyrene-diol-epoxide deoxyguanosine monoclonal antibodies) were acid hydrolyzed (0.1 N HCl, 90 degrees C, 3 h) and the resulting DNA lung hydrolyzates separated by high performance liquid chromatography. Relevant fractions were combined with a solid matrix support which consisted of a mixture of alpha-cyclodextrin (alpha-CD):NaCl (1:9) or alpha-CD:TINO3: aNO3 (1:1:8). The dried and powdered sample-matrix material was analyzed by phosphorescence spectroscopy at room temperature. Certain fractions of human lung samples were found to contain materials that yielded phosphorescence spectra that were indistinguishable from those produced when an authentic r-7, t-8, t-9, c-10-tetrahydroxy-7,8,9,10-tetrahydrobenzo[a]pyrene reference standard was analyzed. The data confirm previous studies that have reported the presence of r-7, t-8 dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene-DNA adducts in human tissues at levels of 1 adduct/10(7)-10(8) nucleotides. The alpha-cyclodextrin solid matrix, room temperature phosphorescence technique was performed with a commercially available instrument, but is 50 times more sensitive than the synchronous fluorescence spectroscopic technique previously used.