“…The biocompatibility and chemical inertness of diamond make it widely used in biology and medicine. 7,8) Extremely low-frequency magnetic field has great value in biological research, which can directly exert influence biological tissue, such as some researchers have confirmed that the use of extremely low-frequency magnetic fields can inhibit the growth of cancer cells without causing lymphocyte necrosis; 9,10) on the other hand, by detecting the extremely low-frequency magnetic field generation by the organism itself to identify the biological state, it has been applied in some experiments, such as in the biological magnetic field research of the human heart, [11][12][13] it is found that the cardiac magnetic field is an extremely lowfrequency magnetic field, at the same time, influenced by the changes in cardiac physiological characteristics, which is used in the diagnosis of heart disease or potential disease. In addition, diamond is also used in battery testing, 14) IC imaging, 15,16) current sensing, [17][18][19] and other fields.…”