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Ultrasound-assisted emulsification microextraction was applied for the extraction and preconcentration of the sulfonylurea herbicides from orange juice sample prior to their determination by HPLC with diode-array detection.Parameters that affect the extraction efficiency, such as the kind and volume of the extraction solvent, emulsification time, sample acidity, extraction temperature and addition of salt, were optimized.Under the optimum extraction condition, the method yields a linear calibration curve in the concentration range from 5 to 1000 ng mL-1 for target analytes.The enrichment factors in the range of 52-140 and the limits of detection in the range of 1-4 ng mL-1 were obtained for the analytes.The proposed method was used for the extraction of the sulfonylurea herbicides from orange juice samples from the local supermarket.The recoveries were in the range of 83-99%, and the repeatability of the method expressed as RSD (n=6) varied between 2.9 and 4.6%.