Journal de la nanomédecine et de la nanotechnologie

Abstrait

An Early Cancer Diagnosis Platform based on Micro-magnetic Sensor Array Demonstrates Ultra-high Sensitivity

Nan Yang, Tao Li, Ping Ping Zhang, Xiaoqiang Chen, Xuefeng Hu and Wei Zhang

In this paper a highly sensitive detection methodology for obtaining the concentration of protein tumor markers via the selective incorporation of super paramagnetic iron oxide nanoparticles (MNP) onto an antigen is reported. The tumor marker concentration is measured with a nano-oxide layer inserted giant magneto-resistive (GMR) sensor that determines the attenuation of an external magnetic field that is induced by the MNP. The 15 nm MNPs, used herein, exhibit a super paramagnetic behavior with saturation magnetization of 36 emu/g. The output voltage signal of the Specular GMR sensor is 500 μV/Oe. The patterned GMR multiple-bio-sensor array, has demonstrated real-time measurements of carcinoembryonic antigen (CEA) protein concentrations down to femtomole level (10-15 mole) in a variety of clinically relevant media with a linear dynamic range of over five orders of magnitude. The sensitivity of the GMR bio-array platform is 1000 times higher than conventional enzyme-linked immunosorbent assay (ELISA) technique. The arrays of magnetoresistive sensors offer great promise in applications for early cancer diagnosis.