This paper proposes an integrated micro-chip for the manipulation and detection of magnetic particles (MPs). A conducting ring structure is used to manipulate MPs toward giant magnetoresistance (GMR) sensing elements for rapid detection. The GMR sensor is fabricated in a horseshoe shape in order to detect the majority of MPs that are trapped around the conducting structure. The GMR sensing elements are connected in a Wheatstone bridge circuit topology for optimum noise suppression. Full fabrication details of the micro-chip, characterization of the GMR sensors, and experimental results with MPs are presented in this paper. Experimental results showed that the micro-chip can detect MPs from low concentration samples after they were guided toward the GMR sensors by applying current to the conducting ring structure.

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