# A Novel Magnetic Respiratory Sensor for Human Healthcare
###### Abstract  
Breathing is vital to life. Therefore, the real-time monitoring of a patient's breathing pattern is crucial to respiratory rehabilitation therapies, such as magnetic resonance exams for respiratory-triggered imaging, chronic pulmonary disease treatment, and synchronized functional electrical stimulation. While numerous respiratory devices have been developed, they are often in direct contact with a patient, which can yield limited data. In this study, we developed a novel, non-invasive, and contactless magnetic sensing platform that can precisely monitor a patient's breathing, movement, or sleep patterns, thus providing efficient monitoring at a clinic or home. A magneto-LC resonance (MLCR) sensor converts the magnetic oscillations generated by a patient's breathing into an impedance spectrum, which allows for a deep analysis of one's breath variation to identify respiratory-related diseases like COVID-19. Owing to its ultrahigh sensitivity, the MLCR sensor yields a distinct breathing pattern for each patient tested. It also provides an accurate measure of the strength of a patient's breath at multiple stages as well as anomalous variations in respiratory rate and amplitude. The sensor can thus be applied to detect symptoms of COVID-19 in a patient, due to shortness of breath or difficulty breathing, as well as track the disease's progress in real time. breathing; respiratory; magnetic sensor; rehabilitation therapies; healthcare +
Footnote †: journal: MedicalOne well-known method to detect the virus is based on the reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) [6; 7]. By collecting samples from subjects and using the reverse transcriptase enzyme, a complementary viral DNA (cDNA) is created from the RNA of the virus. Some portions of cDNA go through a polymerase chain reaction and can thus be detected after an amplification process [8]. Another method for detecting COVID-19 uses an electronic sensor. A field-effect transistor (FET), which can bind to COVID-19, has been developed, and real-time changes to the electric signal have been demonstrated [9]. Optical biosensors and biochemical tests have also been employed to detect this deadly virus [10; 11; 12]. Despite the advantages they provide, these sensors are vulnerable to human contact and inaccuracy with small amounts of samples and usually have long processing times [13]. Common symptoms of COVID-19 include (i) shortness of breath or difficulty breathing, (ii) cough, and (iii) fever. Some patients suffer symptoms similar to lung disease, such as pneumonia [5]. During the infection period, a patient likely experiences shortness of breath or difficulty breathing, which can be detected using a real-time respiratory monitoring device [15; 16; 17]. Current respiratory monitoring techniques are based on the impedance pneumography of respiratory inductance plethysmography (RIP). By attaching electrodes to a patient's chest, the expansion and contraction of the chest causes a change in electrical impedance that can be expressed as the motion of respiration [16]. However, this contact-based method comes with limited sensitivity and reliability, as it usually interferes with natural breathing and requires additional devices for analysis [17]. It is also an inconvenient method to perform actual tests, such as children's respiratory monitoring. Therefore, there is an urgent need for the development of contactless devices that enable early and fast detection of COVID-19, or related diseases, and track their growth rates in real time. In this paper, we present a novel, non-invasive, and contactless magnetic sensing platform that integrates an ultrasensitive magneto-LC resonance (MLCR) sensor with a tiny permanent magnet for applications in healthcare monitoring. We demonstrate how to use this sensing platform to monitor respiratory motion (frequency, amplitude, shortness of breath, etc.)