Recent advances in magnetoresistance biosensors: a short review

Abstract

Recent years have seen the development of spintronic devices and their applications in biomedical areas. Spintronic devices rely on detecting or manipulating a magnetic field, a field to which biological matter is relatively transparent. The recent use of spintronic devices in biomedical areas has included diagnosing diseases such as cancer and cirrhosis, genotyping DNA, point-of-care devices, and flexible electronics. Up to date, most of the spintronic devices in biomedical applications fall into three mainstream types: anisotropic, giant, and tunneling magnetoresistance devices. Each of these has its advantages and drawbacks, which this review explores and discusses. The advent of spintronics gives us a new low-power, low-cost, ease-of-manufacture alternative to standard CMOS sensors. The sensitivity of spintronic biosensors has been progressing steadily, expected to increase tremendously in the next few years.

Flexible Magnetic Field Nanosensors for Wearable Electronics: A Review

“…When the magnetizations in the neighboring FM layers are aligned parallel (i.e., in a “parallel” or “P” configuration), the resistance of the multilayer structure is lower. When the magnetizations are antiparallel (i.e., in an “antiparallel” or “AP” configuration), the resistance is higher. , The MR ratio of a GMR (the same applies to a magnetic tunnel junction which will be introduced in section ) is defined as M R = Δ R R P = R A P − R P R P × 100 % where R AP and R P are the resistance of the device when the magnetizations are in antiparallel and parallel configurations, respectively. Sometimes, the sensitivity of a MR sensor is defined by the slope of the MR ratio over the external field H S = d M R d H …”

“…When the magnetizations are antiparallel (i.e., in an "antiparallel" or "AP" configuration), the resistance is higher. 30,114 The MR ratio of a GMR (the same applies to a magnetic tunnel junction which will be introduced in section 3.2) is defined as (3) where R AP and R P are the resistance of the device when the magnetizations are in antiparallel and parallel configurations, respectively. Sometimes, the sensitivity of a MR sensor is defined by the slope of the MR ratio over the external field H resistance is typically on the order of a few percent, which is significantly larger compared to the changes in resistance observed in ordinary metals.…”

“…When the magnetizations are antiparallel (i.e., in an "antiparallel" or "AP" configuration), the resistance is higher. 30,114 The MR ratio of a GMR (the same applies to a magnetic tunnel junction which will be introduced in section 3.2) is defined as…”

Resonance-Based Sensing of Magnetic Nanoparticles Using Microfluidic Devices with Ferromagnetic Antidot Nanostructures

“…For example, Sun et al have developed an MNP detector that employs an external permanent magnet to direct magnetic nanoparticles through a microfluidic device and onto a sensing surface [ 21 ]. Switching to magnetic particles also enables alternative detection methods based on MNP-induced changes in a static magnetic property such as magnetoresistance (MR) [ 5 , 22 , 23 , 24 , 25 ]. Magnetoresistive detection of MNPs has been demonstrated in a wide variety of devices using techniques such as giant magnetoresistance (GMR), tunneling magnetoresistance (TMR) and anisotropic magnetoresistance (AMR) sensing [ 5 , 22 , 26 , 27 , 28 ].…”

Review—Potential of Tunneling Magnetoresistance Coupled to Iron Oxide Nanoparticles as a Novel Transducer for Biosensors-on-Chip

“…12 Currently, the three major magnetoresistance (MR) transducers being prospected for biosensor application are Anisotropic Magneto-resistance (AMR), Giant Magnetoresistance (GMR), and Tunneling Magnetoresistance (TMR). 13,14 Currently, MR-based sensors are widely used in emerging technologies such as spintronics 15 and quantum computing. 16 These devices are utilized in automotive, industrial, and medical applications, including location, rotation, and current sensing.…”