# US 11,110,052 B2 · 3D navigation of nanoparticles via induction of metastable diamagnetic response > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,110,052 B2 - Document ID: US11110052B2 - Status: Granted - Kind: B2 - Application number: 16/417,898 - Filed: 2019-05-21 - Published: 2020-03-19 - Granted: 2021-09-07 - Earliest claimed: 2018-09-14 - Assignees: The Florida International University Board of Trustees - Applicants: Sakhrat Khizroev; Tiffanie Stewart; Abhignyan Nagesetti - Inventors: Sakhrat Khizroev; Tiffanie Stewart; Abhignyan Nagesetti - Web page: https://patentgrep.com/patent/US11110052B2 ## CPC - A61K 9/0009: {involving or responsive to electricity, magnetism or acoustic waves; Galenical aspects of sonophoresis, iontophoresis, electroporation or electroosmosis} - A61B 5/0515: Magnetic particle imaging - A61K 41/00: Medicinal preparations obtained by treating materials with wave energy or particle radiation {; Therapies using these preparations} - A61N 2/004: {specially adapted for a specific therapy} - A61B 5/0042: {for the brain} - A61B 5/4839: {combined with drug delivery} - B82Y 5/00: Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES ## Abstract Methods and devices for three-dimensional navigation of magnetic nanoparticles are provided. A method can comprise introducing high-anisotropy magnetic nanoparticles to a mammal and directing the high-anisotropy magnetic nanoparticles towards a target region of the mammal. Direction control is achieved by subjecting the high-anisotropy magnetic nanoparticles to an alternating signal comprising a uniform magnetic field pulse having a strength greater than a coercivity of the high-anisotropy magnetic nanoparticles and a magnetic gradient pulse having a highest strength that is less than the coercivity of the high-anisotropy magnetic nanoparticles and a location of a lowest strength at the target region of the mammal, and the direction of the uniform magnetic field pulse being in an opposite direction of the magnetic gradient pulse. ## Claims ### Claim 1 A method of three-dimensional navigation of magnetic nanoparticles, the method comprising: introducing low-anisotropy magnetic nanoparticles to a mammal; and directing the low-anisotropy magnetic nanoparticles towards a target region of the mammal by: subjecting the low-anisotropy magnetic nanoparticles to an alternating signal comprising a uniform magnetic field pulse having a strength greater than a coercivity of the low-anisotropy magnetic nanoparticles and a magnetic gradient pulse having an initial location of a lowest strength at the target region of the mammal, the direction of the uniform magnetic field pulse being opposite of the direction of magnetic gradient pulse. ### Claim 2 (depends on 1) The method according to claim 1, further comprising adjusting a spin relaxation time of a low-anisotropy magnetic nanoparticle of the low-anisotropy magnetic nanoparticles comprising adjusting a size of the of the low-anisotropy magnetic nanoparticle. ### Claim 3 (depends on 2) The method according to claim 2, the low-anisotropy magnetic nanoparticles comprising iron. ### Claim 4 (depends on 1) The method according to claim 1, further comprising adjusting a spin relaxation time of a low-anisotropy magnetic nanoparticle comprising adjusting a strength of the magnetic gradient pulse. ### Claim 5 (depends on 4) The method according to claim 4, the low-anisotropy magnetic nanoparticles comprising iron. ### Claim 6 (depends on 1) The method according to claim 1, a time duration of the uniform magnetic field pulse being equal to a time duration of the magnetic gradient pulse. ### Claim 7 (depends on 6) The method according to claim 6, the low-anisotropy magnetic nanoparticles comprising iron. ### Claim 8 (depends on 1) The method according to claim 1, a respective time duration of each of the uniform magnetic field pulse and the magnetic gradient pulse being dependent upon a spin relaxation time at a particular strength of the magnetic gradient pulse. ### Claim 9 (depends on 8) The method according to claim 8, the low-anisotropy magnetic nanoparticles comprising iron. ### Claim 10 (depends on 1) The method according to claim 1, further comprising: altering a direction of the low-anisotropy magnetic nanoparticles by adjusting the location of the lowest strength of the magnetic gradient pulse. ### Claim 11 (depends on 10) The method according to claim 10, the low-anisotropy magnetic nanoparticles comprising iron. ### Claim 12 (depends on 1) The method according to claim 1, the uniform magnetic field pulse and the magnetic gradient pulse being applied by an electromagnet comprising a conductive wire wrapped in a coil. ### Claim 13 (depends on 12) The method according to claim 12, the conductive wire being wrapped around a magnetic core. ### Claim 14 (depends on 12) The method according to claim 12, the low-anisotropy magnetic nanoparticles comprising iron. ### Claim 15 (depends on 1) The method according to claim 1, the low-anisotropy magnetic nanoparticles comprising iron. ### Claim 16 (depends on 1) The method according to claim 1, a time duration of the uniform magnetic field pulse being equal to a time duration required for the low-anisotropy magnetic nanoparticles to physically rotate 180 degrees inside the mammal. ### Claim 17 (depends on 16) The method according to claim 16, a time duration of the magnetic gradient pulse being equal to the time duration required for the low-anisotropy magnetic nanoparticles to physically rotate 180 degrees inside the mammal. ### Claim 18 (depends on 17) The method according to claim 17, the low-anisotropy magnetic nanoparticles comprising iron. ### Claim 19 (depends on 1) The method according to claim 1, a time duration of the magnetic gradient pulse being equal to a time duration required for the low-anisotropy magnetic nanoparticles to physically rotate 180 degrees inside the mammal. ### Claim 20 A method of three-dimensional navigation of magnetic nanoparticles, the method comprising: introducing low-anisotropy magnetic nanoparticles to a mammal; and directing the low-anisotropy magnetic nanoparticles towards a target region of the mammal by: subjecting the low-anisotropy magnetic nanoparticles to an alternating signal comprising a uniform magnetic field pulse having a strength greater than a coercivity of the low-anisotropy magnetic nanoparticles and a magnetic gradient pulse having an initial location of a lowest strength at the target region of the mammal, the direction of the uniform magnetic field pulse being opposite of the direction of magnetic gradient pulse, adjusting a spin relaxation time of a low-anisotropy magnetic nanoparticle of the low-anisotropy magnetic nanoparticles comprising adjusting a size of the of the low-anisotropy magnetic nanoparticle and a strength of the magnetic gradient pulse, the low-anisotropy magnetic nanoparticles comprising iron, a time duration of the uniform magnetic field pulse being equal to a time duration of the magnetic gradient pulse, the time duration of the uniform magnetic field pulse and the time duration of the magnetic gradient pulse being dependent upon a spin relaxation time at a particular strength of the magnetic gradient pulse, the method further comprising altering a direction of the low-anisotropy magnetic nanoparticles by adjusting the location of the lowest strength of the magnetic gradient pulse, the uniform magnetic field pulse and the magnetic gradient pulse being applied by an electromagnet comprising a conductive wire wrapped in a coil, the conductive wire being wrapped around a magnetic core, the time duration of the uniform magnetic field pulse being equal to a time duration required for the low-anisotropy magnetic nanoparticles to physically rotate 180 degrees inside the mammal, and the time duration of the magnetic gradient pulse being equal to the time duration required for the low-anisotropy magnetic nanoparticles to physically rotate 180 degrees inside the mammal.