Permanent magnet keeper-shield assembly
AssigneeFeRx Incorporated
InventorsRobert Mitchiner, Thomas B. Kent, Caryn Peterson, Scott Raymond Rudge
Life of this patent
Estimating the term…
Abstract
A magnet keeper-shield assembly adapted to hold and store a permanent magnet used to generate a high gradient magnetic field. Such a field may penetrate into deep targeted tumor sites in order to attract magnetically responsive micro-carriers. The magnet keeper-shield assembly includes a magnetically permeable keeper-shield with a bore dimensioned to hold the magnet. A screw driven actuator is used to push the magnet partially out of the keeper-shield. The actuator is assisted by several springs extending through the base of the keeper-shield.
Claims20
A magnet keeper-shield assembly for housing a magnet, said magnet keeper-shield assembly comprising:
- a keeper-shield comprising a material substantially permeable to a magnetic flux;
- a cavity in the keeper-shield, said cavity comprising an inner side wall and a base, and said cavity being adapted to accept a magnet having a front and a bottom face;
- an actuator extending through the base;
- a plurality of springs extending through the base, said springs operative to exert a force in a range from about 175 pounds to about 225 pounds on the bottom face of the magnet in a retracted position, and
- wherein said magnet produces at least about 118 gauss at a distance of about 10 cm from the front face in the extended position and produces at most about 5 gauss at a distance less than or equal to about 22 cm from the front face in the retracted position.
A method of in vivo delivery of magnetic particles, the method comprising:
- administering a composition into a patient, said composition comprising magnetic particles;
- extending a magnet having a front and a bottom face from a shielding keeper-shield to produce at least about 118 gauss at a distance of about 10 cm from the front face;
- positioning said magnet over a desired location on the patient;
- and
- directing said particles to a desired location in the patient with the use of a magnetic field provided by said magnet.
A method for decreasing systemic toxicity of a drug comprising:
- preparing a composition comprising magnetic particles in combination with said drug;
- administering said composition into a patient;
- extending a magnet having a front and bottom face from a keeper-shield to produce at least about 118 gauss at a distance of about 10 cm from the front face;
- positioning said magnet over a desired location on the patient;
- and
- directing said magnet particles to the desired location in the patient with the use of a magnetic field provided by said magnet.
A method for decreasing systemic circulation of agents selected from the group consisting of diagnostic, therapeutic, and combinations thereof, comprising:
- preparing a composition comprising magnetic particles in combination with said agent;
- administering the composition into a patient, said composition comprising magnetic particles having the agent attached thereon;
- positioning a permanent magnet over a desired location on the patient;
- and
- directing said magnetic particles to the desired location in the patient with the use of a magnetic field provided by said magnet.
A method for providing variable field strength from a permanent magnet comprising extending the magnet from a keeper-shield assembly, wherein the keeper-shield assembly comprises:
- a keeper-shield comprising a material substantially permeable to magnetic flux;
- a cavity in the keeper-shield, said cavity comprising an inner side wall and a base, and said cavity being adapted to accept a magnet having a front and a bottom face;
- an actuator extending through the base;
- a plurality of springs extending through the base, said springs operative to exert a force in a range from about 175 pounds to about 225 pounds on the bottom face of the magnet in a retracted position;
- and
- wherein said magnet produces at least about 118 gauss at a distance of about 10 cm from the front face in the extended position and produces at most about 5 gauss at a distance less than or equal to about 22 cm from the front face in the retracted position.
Dependencies are inferred from the claim text.