DETERMINATION OF DELTA-AMINOLEVULINIC-ACI D IN BLOOD USING STOPPED-FLOW HPLC

Stopped-flow HPLC (SF-HPLC) was applied to determine delta-aminolevuli nic acid in blood (ALA-B) using a reverse phase column after simple pr etreating method. The highest fluorescent intensity was obtained when the pretreated sample was doubly diluted with 100 mM sodium acetate (p H 5.0), introduced 60 mul of the sample into the condensing coil at te mperature of 98-degrees-C, firstly added to 50% acetylacetone in 25% e thanol, and secondary mixed with 10% formaldehyde solution. The detect ion limit was 2 mug/l which was 2.5 times higher than that by conventi onal method, and measuring time per sample was 13 min. Relative standa rd deviations of 10 blood samples calculated from 4-time determination s per sample for 1 week were within 5%. ALA-B of 35 lead-exposed and n on-exposed workers determined by the SF-HPLC method was closely correl ated with the conventional HPLC method (r = 0.97). Moreover, this meth od could prevent an analyzer from exposure to hazardous chemicals such as formaldehyde and acetylacetone.