Learn More
A high density GMR sensor array was integrated with a standard CMOS chip for DNA hybridization detection. Absorption of magnetic nanoparticles by the hybridized DNA alters the sensor resistance, and generated electrical signals are directly measured with the on-die circuitry. The proposed biochip can be applied to other bio-reaction detection, e.g. protein(More)
In this paper, we present a study comparing the recording performance of perpendicular and longitudinal media. In particular the synchronization requirements of the two cases are compared. A model, which includes media properties, such as easy-axis orientation, switching field distribution (SFD), and head properties, such as head field gradient, is able to(More)
We have developed a simple method using a magnetic bar array to anchor nonmagnetic biomolecules for time-lapse analysis and identification. Biomolecules of interest are attached, using linker molecules, to the superparamagnetic beads which are in turn captured at gaps of the magnetic bar array. This micro-array system can be used for various studies and(More)
In this paper, the main challenges in developing a magnetic DNA microarray include: 1) The spin valve sensors must be sensitive to as few as 1-10 nanobeads to be useful for applications such as biological pathogen detection; to achieve this, the distance between the sensor and magnetic labels must be minimized. 2) The nanobeads must be monodisperse, water(More)
Giant magnetoresistive (GMR) sensors are developed for a DNA microarray. Compared with the conventional fluorescent sensors, GMR sensors are cheaper, more sensitive, can generate fully electronic signals, and can be easily integrated with electronics and microfluidics. The GMR sensor used in this work has a bottom spin valve structure with an MR ratio of(More)
We have developed a simple elegant system based on an array of thin-film magnetic bars for creating a two-dimensional array of paramagnetic polymer beads that can be functionalized to bind fluorescently labeled DNA fragments. The resulting array can be scanned using conventional optical fluorescence instruments, to quantify the relative abundance of(More)
  • 1