Aromatic amines such as aniline and its derivatives are widely used in industry, production of dyes and antioxidants, cosmetics, pesticides, pharmaceuticals and as the intermediate in many chemical syntheses, but, it is well known that these compounds are carcinogens and have been implicated in inducing cancer of the bladder [1,2]. The main aim of this research is to develop the preconcentration and sample preparation method, based on two liquid phase microextraction procedure prior to UV-Vis spectrophotometer. The target compoun(3-nitroaniline) was extracted from an aqueous sample solution (donor phase) into an organic solvent (acceptor phase). In this method, contrary to the ordinary single drop liquid-phase microextraction technique [3,4], a large drop of an organic solvent is freely suspended at the bottom of the vortex of the aqueous sample solution which is being agitated by a stirring bar, without using a microsyring as supporting device. The organic solvents which are used in this work should be insoluble or have very low solubility in water. After an optimal extraction time, a portion of the organic drop was withdrawn back into a 500 μL HPLC microsyringe and then inserted into a quartz microcell. For reducing the volume of the organic acceptor phase, the internal volume of this microcell is decreased by adding of about 90 μL of water which is placed in the bottom of the cell where is not in the optical path. Several important parameters which inuence the extraction efficiency, such as the kind of extracting solvent, volume of the organic acceptor phase, extraction time, stirring rate, pH of the donor phase and salt effect were investigated. Under the optimal conditions the enrichment factor was 36. By plotting peak areas versus concentrations of the analyte in the sample solution, calibration curve was obtained with correlation coefficient of 0.9986. The linearity of the method has been investigated between the ranges of 6-100 ng mL-1. The precision of the method (RSD %) and the limit of detection (LOD) was 5 and 2 ng mL-1, respectively. The performance of the proposed technique was evaluated for the determination of 3-nitroaniline in different environmental water samples andthe obtained relative recoveries were above than 90 %.

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