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A microfluidic chip has been fabricated for bladder cancer detection based on urinalysis.Bladder cancer cells and float leukocytes in the urine have been trapped by the micro channels of the chip.Bladder cancer cells have been distinguished from leukocytes due to their different electrical capacitance.This paper introduces an integrated microfluidic chip as a promising tool to measure the concentration of bladder cancer cells (BCC) in urine samples. Silicon microchannels were used as trapping gates for both floated BCC and leukocytes which are found in the urine of patients. By the assistance of the gold electrodes patterned at the bottom of the micro gates, the capacitance of captured cancerous and blood cells were measured. Different membrane capacitance between BCC and leukocyte was the indicative signal for diagnosing the nature of captured cells in a urine like solution. The concentration range of the target that could be detected was about 10 BCCs per one chip. Such response has been achieved without applying any biochemical or florescent markers. Thus, it could be a simple and cheap approach to support cytological and immune-fluorescent assays. The limit of detection was approximately 1 cancerous cell/11 leukocytes in 1 ml of the urine like solution. The entire measurement time was less than an hour. Consequently, this electrical microfluidic device promises significant potential in urinalysis.