巨磁阻生物传感器对磁性聚苯乙烯微球检测

采用改进的悬浮聚合法制备磁性聚苯乙烯微球.利用扫描电子显微镜和振动样品磁强计对所合成磁性微球的尺寸和磁性能进行分析表征.采用巨磁阻生物传感器检测磁性微球的数量.结果表明:磁性微球粒径大小为0.5～50μm,比饱和磁化强度为4.56 A.m2.kg-1.巨磁阻生物传感器对磁性聚苯乙烯微球数量具有很好的可检测性.在一定的范围内,随着磁性微球数量的增多,传感器的输出信号增强.在磁性微球一定数量的情况下,随着磁性微球粒径的增大,传感器的电阻变化量先增大后减小.

Detection of magnetic polystyrene microspheres by a giant magnetoresistance biosensor

Magnetic polystyrene microspheres were prepared by a modified suspension polymerization method and were characterized by scanning electron microscopy(SEM) and vibrating sample magnetometry(VSM).The number of the magnetic microspheres was detected with a giant magnetoresistance biosensor.The results show that the magnetic microspheres are spherical,their sizes range from 0.5 to 50 μm,and their specific saturation magnetization is 4.56 A·m2·kg-1.The magnetic microspheres have a very good response to the sensor.With the amount of the magnetic microspheres increasing,the output signal of the biosensor intensifies.Under a given amount of the magnetic microspheres,the change in electrical resistivity of the sensor increases first and then decreases with the increase of the magnetic microsphere size.