Determination of naphthalene by competitive fluorescence immunoassay

A reliable and sensitive competitive fluorescence immunoassay for the quantitative determination of naphthalene (NA) was developed. 2-naphthoxy acetic acid (NAA) was selected as the hapten of naphthalene. Active ester method (AEM) was used to couple the NAA to carrier proteins (bovine serum albumin) to form artificial immune antigen. Male New Zealand white rabbits were immunized with this antigen to obtain polyclonal antibodies, with which, a novel fluorescence immunoassay for detection of NA was described. Under best conditions, NA can be determined in the concentration range of 0.1-100 microg/L with a detection limit of 0.05 microg/L. The cross-reactivities of the anti-NA antibody to seven structurally related compounds were below 15%. Some environmental samples were analyzed with satisfactory results. It shows a good accuracy and suitability to analyze NA in environmental water.