A rapid fluorescent method for estimation of free erythrocyte protoporphyrin (FEP) is described. Simple ethyl acetate-glacial acetic acid extractions are performed, fluorescence quantitated in a fluorimeter and expressed numerically by comparison with known coproporphyrin standards.
Fifty-six children were studied and the extent of lead poisoning was evaluated initially and at different follow-up intervals. A clear relationship was shown between FEP fluorescence and blood lead levels. A correlation was also seen for the intensity of fluorescence and evidence for increased absorption of lead, as estimated by x-ray evidence of ingested lead and deposits in bone. Children with iron deficiency anemia also showed elevations of FEP fluorescence.
This FEP fluorescence test allows for a rapid, numerical determination which appears to be useful as a screening test for lead intoxication. It can quickly select patients that may have markedly increased lead absorption and need prompt therapy or select those that at least require further studies for possible lead exposure or the presence of anemia.
Use of a molecular beacon based fluorescent method for assaying uracil DNA glycosylase (Ung) activity and inhibitor screening