Medical device with low magnetic susceptibility

• US 20050025797A1
• Filed: 07/07/2004
• Published: 02/03/2005
• Est. Priority Date: 04/08/2003
• Status: Abandoned Application

• Current Assignee: Biophan Technologies Incorporated
• Original Assignee: Biophan Technologies Incorporated
• Inventors: Greenwald, Howard Jay, Wang, Xingwu
• Application Number:
  US10/887,521
• Publication Number:
  US 20050025797A1
• Time in Patent Office: Days
• US Class Current: 424/422
• CPC Class Codes: A61L 2300/00 Biologically active materials used in bandages, wound dressings, absorbent pads or medical devices
• CPC Class Codes: A61L 31/16 Biologically active materials, e.g. therapeutic substances A61L31/047 takes precedence
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance

Abstract

An assembly that contains a medical device and biological material within which the medical device is disposed. The assembly has a magnetic susceptibility within the range of plus or minus 1×10⁻³ centimeter-gram-seconds

Claims

1. An assembly comprised of a medical device and biological material within which said medical device is disposed, wherein said assembly has a magnetic susceptibility within the range of plus or minus 1×

10<sup>−

3</sup> centimeter-gram-seconds.

2. The assembly as recited in claim 1, wherein said assembly is an implantable assembly.

3. The assembly as recited in claim 2, wherein said assembly is comprised of nanomagnetic material comprising nanomagnetic particles.

4. The assembly as recited in claim 3, wherein:

(a) said nanomagentic particles have an average particle size of less than about 100 nanometers;

(b) the average coherence length between adjacent nanomagnetic particles is less than 100 nanometers; and

(c) said nanomagnetic material has a saturation magentization of from about 2 to about 3000 electromagnetic units per cubic centimeter, a phase transition temperature of from about 40 to about 200 degrees Celsius, and a saturation magnetization of from about 2 to about 3,000 electromagnetic units per cubic centimeter.

5. The assembly as recited in claim 4, wherein said assembly is comprised of a first therapeutic agent.

6. The assembly as recited in claim 5, wherein said first therapeutic agent is an anti-cancer drug.

7. The assembly as recited in claim 5, wherein said first therapeutic agent is an anti-mitotic agent.

8. The assembly as recited in claim 4, wherein said nanomagnetic material has an average particle size of less than about 20 nanometers and a phase transition temperature of less than about 50 degrees Celsius.

9. The assembly as recited in claim 4, wherein said assembly further comprises a cytotoxic radioactive material.

10. The assembly as recited in claim 4, wherein said assembly is comprised of a material that is absorbable in living tissue.

11. The therapeutic assembly as recited in claim 10, wherein said material that is absorbable in living tissue is selected from the group consisting of polyester amides from glycolic acids, polyester amides from lacitic acids, polymers and copolymers of gylcolate, polymers and copolymers of lactatate, and poolydioxanone.

12. The assembly as recited in claim 4, wherein said medical device is comprised of a polymeric material selected from the group consisting of a silicon-containing polymeric material and a hydrocarbon-containing polymeric material.

13. The assembly as reciteed in claim 4, wherein said medical device is comprised of a polymeric material.

14. The assembly as recited in claim 13, wherein said polymeric material is comprised of said first therapeutic agent.

15. The assembly as recited in claim 14, wherein said polymeric material is comprised of a second therapeutic agent.

16. The assembly as recited in claim 15, wherein said polymeric material is comprised of a third therapeutic agent.

17. The assembly as recited in claim 13, wherein said polymeric material is a drug-eluting polymer.

18. The assembly as recited in claim 13, wherein said polymeric material is silicone rubber.

19. The assembly as recited in claim 18, wherein said silicone rubber is dimethylpolysiloxane rubber.

20. The therapeutic as recited in claim 18, wherein said silicone rubber is a biocompatible silicone rubber.

21. The assembly as recited in claim 13, wherein said polymeric material is a synthetic absorbable copolymer formed by copolymereizing glycolide with trimethylene carbonate.

22. The assembly as recited in claim 13, wherein said polymeric material is selected from the group consisting of silk, polyester, polytetrafluoroethylene, polyurethane silicone-based material, and polyamide.

23. The assembly as recited in claim 13, wherein said polymeric material is a bioresorbable polyester.

24. The assembly as recited in claim 13, wherein said polymeric material is a copolymer containing carbonate repeat units and ester repeat units

25. The assembly as recited in claim 13, wherein said polymeric material is collagen.

26. The assembly as recited in claim 13, wherein said polymeric material selected from the group consisting of homopolymers and copolymers of glycolic acid and lactic acid.

27. The assembly as recited in claim 13, wherein said polymeric material is a polycarbonate-containing polymer.

28. The assembly as recited in claim 13, wherein said polymeric material is selected from the group consisting of polylactic acid, polyglycolic acid, copolymes of polylactic acid and polyglycolic acid, polyamides, and copolyesters of polyamides and polyestes.

29. The assembly as recited in claim 13, wherein said polymeric material is selected from the group consisting of polyesters, polyamides, polyurethanes, and polyanhydrides.

30. The assembly as recited in claim 13, wherein said polymeric material is a poly (phosphoester).

31. The assembly as recited in claim 5, wherein said first thereapeutic agent is selected from the group consisting of proteinaceous drugs and non-proteinaceous drugs.

32. The assembly as recited in claim 5, wherein said first therapeutic agent is a biological response modifier.

33. The assembly as recited in claim 5, wherein said first therapeutic agent is an immune modifier.

34. The assembly as recited in claim 33, wherein said immune modifier is a lymphokine.

35. The assembly as recited in claim 34, wherein said lymphokine is selected from the group consisting of tumor necrosis factor, interleukin, lymphotoxin, marcropahge activating factor, migration inhibition factor, colony stinulating factor, and interferon.

36. The assembly as recited in claim 5, wherein said first therapeutic agent is a lectin.

37. The assembly as recited in claim 13, wherein said polymeric material is a polypeptide.

38. The assembly as recited in claim 13, wherein said polymeric material is comprised of a first drug-binding domain.

39. The assembly as recited in claim 38, wherein said polymeric material is comprised of a second drug-binding domain.

40. The assembly as recited in claim 5, wherein said assembly is comprised of a reservoir for said therapeutic agent.

41. The assembly as recited in claim 40, wherein said therapeutic agent is selected from the group consisting of antithrombogenic agents, antiplatelet agents, prostaglandins, thrombolytic drugs, antiproliferative drugs, antirejection drugs, antimicrobial drugs, growth factors, anticalcifying agents, and mixtures thereof.

42. The assembly as recited in claim 41, wherein said reservoir is formed by a polymer selected from the group consisting of polyurethanes and its copolymers, silicone and its copolymers, ethylene vinylacetat, thermoplastic elastomers, polyvinylchloride, polyolefins, cellulosics, polyamides, polytetrafluoroethylenes, polyesters, polycarbonates, polysulfones, acrylics, and acrylonitrile butadiene styrene copolymers.

43. The assembly as recited in claim 13, wherein said polymeric material is a bioabsorbable polymer selected from the group consisting of poly (L-lactic acid), polycaprolactone, poly (lactide-co-glycolide), poly (hydroxybutyrate), poly (hydroxybutyrate-co-valerate), polydioxanone, polyorthoester, polyanhydride, poly (glycolic acid), poly (D,L-lactic acid), poly (glycolic acid-co-trimethylene carbonate), polyphosphoester, polyphosphoester urethane, poly(amino acid), cyanoacruylate, poly(trimethylene carbonate), poly (iminocarbonate) copoly (ether-ester), polyalkylene oxalate, polyphosphazenes, and mixtures thereof.

44. The assembly as recited in claim 13, wherein said polymeric material is a biomolecule.

45. The assembly as recited in claim 44, wherein said biomolecule is selected from the group consisting of fibrin, fibrogen, cellulose, starch, collagen, and hyaluronic acid.

46. The assembly as recited in claim 13, wherein said polymeric material is selected from the group consisting of polyolefin, acrylic polymer, acrylic copolymer, vinyl halide polymer, vinyl halide copolymer, polyvinyl ether, polyvinylidene halide, polvinylketone, polyvinyl aromatic polymer, copolymers of vinyl monomer, acrylonitrile-styrene copolymer, ethylene-vinyl acetate copolymer, polyamide, alkyd resin, polyoxymethylene, polyimide, polyether, epoxy resin, rayon, rayon-tracetate, cellulose, cellulose acetate, cellulose butyrate, cellulose acetate butyrate, cellophane, cellulose nitrate, cellulose propionate, cellulose ether, and carboxymethyl cellulose.

47. The assembly as recited in claim 5, wherein said first therapeutic agent is selected from the group consisting of glucocorticoids, heparin, hirudin, tocopherol, angiopeptin, aspirin, ACE inhibitors, growth factors, oligonucleotides, antiplatelet agents, anticoagulant agents, antimitotic agents, antioxidants, antimetabolite agents, and anti-inflammatory agents.

48. The assembly as recited in claim 13, wherein a heterobifunctional photolytic linker is bonded to said polymeric material.

49. The assembly as recited in claim 5, wherein said first therapeutic agent is a vasoreactive agent.

50. The assembly as recited in claim 49, wherein said vasoreactive agent is a nitric oxide releasing agent.

51. The assembly as recited in claim 13, wherein said polymeric material is comprised of a multiplicity of microcapsules.

52. The assembly as recited in claim 13, wherein said polymeric material is a mixture of fibrinogen and thrombin.

53. The therapeutic assembly as recited in claim 13, wherein said polymeric material is a multi-layered polymeric material.

54. The therapeutic assembly as recited in claim 13, wherein said polymeric material is a porous polymeric material.

55. The assembly as recited in claim 13, wherein said polymeric material has a thermal processing temperature of less than about 100 degrees Celsius.

56. The therapeutic assembly as recited in claim 13, wherein said polymeric material is comprised of a porosigen.

57. The assembly as recited in claim 56, wherein said porosigen is selected from the group of microgranules of sodium chloride, lactose, sodium heparin, polyethyelen glycol, polyethylene oxide/polypropylene oxide copolymer, and mixtures thereof.

58. The assembly as recited in claim 13, wherein said polymeric material is a thermoplastic polymer.

59. The assembly as recited in claim 13, wherein said polymeric material is an elastomeric polymer.

60. The assembly as recited in claim 13, wherein said polymeric material is in the form of a layer of material with a thickness of from about 0.002 to about 0.02 inches.

61. The assembly as recited in claim 13, wherein said polymeric material is a controlled release polymer.

62. The assembly as recited in claim 61, wherein said controlled release polymer is comprised of a congener of an endothelium-derived bioactive composition.

63. The assembly as recited in claim 62, wherein said congener of an endothelium-derived bioactive agent is selected from the group consisting of nitric oxide, nitric L-arginine, sodium nitroprusside, and nitroglycerine.

64. The assembly as recited in claim 13, wherein said polymeric material is a transparent polymeric material.

65. The assembly as recited in claim 13, wherein said polymeric material is a hydrophobic elastomeric material.

66. The assembly as recited in claim 13, wherein said polymeric material is a hydrophilic polymer.

67. The assembly as recited in claim 5, wherein said first therapeutic agent is a water-soluble therapeutic agent.

68. The assembly as recited in claim 5, wherein said first therapeutic agent is an anti-microtubule agent that impairs the functioning of microtubues.

69. The assembly as recited in claim 68, wherein said anti-microtuble agent is paclitaxel.

70. The assembly as recited in claim 13, wherein said polymeric material is a pH-sensitive polymer.

71. The assembly as recited in claim 70, wherein said pH -sensitive polymer is selected from the group consisting of poly(acrylic acid), poly (aminocarboxylic acid), poly (acrlic acid), poly (methyl acrylic acid), cellulose acetate phthalate, hydroxypropylmethylcellulose phthalate, hydroxypropylmethylcellulose acetate succinate, cellulose acetate trimellilate, and chitosan.

72. The assembly as recited in claim 13, wherein said polymeric material is a temperature-sensitive polymer.

73. The assembly as recited in claim 13, wherein said polymeric material is a thermogelling polymer.

74. The assembly as recited in claim 73, wherein said thermogelling polymer is selected from the group consisting of poly(-methyl-N-n-propylacrlamide), poly(-methyl-N-n-propylacrylamide), poly(N-n-propylacrylamide), poly(N-methyl-N-isopropylacrylamide), poly(N-n-propylmethacrylamide), poly(N-isopropylacrylamide), poly(N,n-diethylacrylamide), poly(N-isopropylmethacrylamide), poly(N-cyclopropylacrylamide), poly(N-ethylmethyacrylamide), poly(N-methyl-N-ethylacrylamide), poly(N-cyclopropylmethacrylamide), and poly(N-ethylacrylamide), hydroxypropyl cellulose, methyl cellulose, hydroxypropylmethyl cellulose, and ethylhydroxyethyl cellulose.

75. The assembly as recited in claim 4, wherein the the average particle size of such nanomagnetic particles is less than about 15 nanometers.

76. The assembly as recited in claim 4, wherein said nanomagentic material has a saturation magnetization of at least 2,000 electromagnetic units per cubic centimeter.

77. The assembly as recited in claim 4, wherein said nanomagnetic material has a saturation magnetization of at least 2,500 electromagnetic units per cubic centimeter.

78. The assembly as recited in claim 4, wherein said particles of said nanomagnetic material have a squareness of from about 0.05 to about 1.0.

79. The assembly as recited in claim 4, wherein said particles of said nanomagnetic material are at least triatomic, being comprised of a first distinct atom, a second distinct atom, and a third distinct atom.

86. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a sqareness of from about 0.1 to about 0.9.

87. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a squarenesss is from about 0.2 to about 0.8.

88. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have an average size of less of less than about 3 nanometers.

89. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have an average size of less than about 15 nanometers.

90. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have an average size is less than about 11 nanometers.

91. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a phase transition temperature of less than 46 degrees Celsius.

92. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a phase transition temperature of less than about 50 degrees Celsius.

93. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a phase transition temperature of less than about 46 degrees Celsius.

94. The assembly as recited in claim 4, wherein said nanomagnetic material has a coercive force of from about 0.1 to about 10 Oersteds.

95. The assembly as recited in claim 4, wherein said particles of nanomagnetic material haa a relative magnetic permeability of from about 1.5 to about 2,000.

96. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a saturation magnetization of at least 100 electromagnetic units per cubic centimeter.

97. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a saturation magnetization of at least about 200 electromagnetic units (emu) per cubic centimter.

98. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a saturation magnetization of at least about 1,000 electromagnetic units per cubic centimeter.

99. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a coercive force of from about 0.01 to about 5,000 Oersteds.

100. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a coercive force of from about 0.01 to about 3,000 Oersteds.

101. The assembly as recited in claim 4, wherein said particles of nanomagnetic material are disposed within a film that has a heat shielding factor of at least 0.2.

102. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a relative magnetic permeability of from about 1 to about 500,000.

103. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a relative magnetic permeability of from about 1.5 to about 260,000.

104. The assembly as recited in claim 4, wherein said assembly is comprised of antithrombogenic material.

105. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a mass density of at least about 0.001 grams per cubic centimeter.

106. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a mass density of at least about 1 gram per cubic centimeter.

107. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a mass density of at least about 3 grams per cubic centimeter.

108. The assembly as recited in claim 4, wherein said particles of nanomagnetic material have a mass density of at least about 4 grams per cubic centimeter.

115. The assembly as recited in claim 14, wherein said nanomagnetic particles are comprised of atoms of iron.

116. The assembly as recited in claim 115, wherein said atoms of iron are atoms of radioactive iron.

117. The assembly as recited in claim 115, wherein said nanomagnetic particles are comprised of atoms of cobalt.

118. The assembly as recited in claim 117, wherein said atoms of cobalt are atoms of radioactive cobalt.

119. The assembly as recited in claim 4, wherein said wherein said nanomagnetic material is disposed within a ceramic binder.

120. The assembly as recited in claim 119, wherein said ceramic binder is selected from the group consisting of a clay binder, an organic colloidal particle binder, and a molecular organic binder.

121. The assembly assembly as recited in claim 4, wherein said nanomagnetic material is disposed within a synthetic polymeric binder.

122. The assembly as recited in claim 4, wherein said nanomagnetic material is disposed within a fiber.

123. The assembly as recited in claim 4, wherein said nanomagnetic material is disposed within a fabric.

124. The assembly as recited in claim 4, wherein said particles of nanomagnetic material are disposed within an insulating matrix.

125. The assembly as recited in claim 4, wherein said particles of nanomagnetic material are present in the form of a coating with a thickness of froma bout 400 to about 2000 nanometers.

126. The assembly as recited in claim 125, wherein said coating has a thickness of from about 600 to about 1200 nanometers.

127. The assembly as recited in claim 126, wherein said coating has a morphological density of at least about 98 percent.

128. The assembly as recited in claim 127, wherein said coating has a morphological density of at least about 99 percent.

129. The assembly as recited in claim 128, wherein said coating has a morphological density of at least about 99.5 percent.

130. The assembly as recited in claim 126, wherein said coating has an average surface roughness of less than about 100 nanometers.

131. The assembly as recited in claim 126, wherein said coating has an average surface roughness of less than about 10 nanometers.

132. The assembly as recited in claim 126, wherein said coating is biocompatiable.

133. The assembly as recited in claim 126, wherein said coating is hydrophobic.

134. The assembly as recited in claim 126, wherein said coating is hydrophilic.

135. The assembly as recited in claim 126, wherein said coating has an average surface roughness of less than about 1 nanometers.

136. The assembly as recited in claim 4, wherein said assembly is comprised of magnetostrictive material.

137. The assembly as recited in claim 4, wherein said assembly is comprised of magnetoresistive material.

84. The assembly as recited in 79, wherein said particles of nanomagnetic material are comprised of a said distinct atom, said second distinct atom, said third distinct atom, and a fourth distinct atom.

80. The assembly as recited in claim 111, wherein said first distinct atom is an atom selected from the group consisting of atoms of actinium, americium, berkelium, californium, cerium, chromium, cobalt, curium, dysprosium, einsteinium, erbium, europium, fermium, gadolinium, holmium, iron, lanthanum, lawrencium, lutetium, manganese, mendelevium, nickel, neodymium, neptunium, nobelium, plutonium, praseodymium, promethium, protactinium, samarium, terbium, thorium, thulium, uranium, and ytterbium.

81. The assembly as recited in claim 80, wherein said first distinct atom is a cobalt atom.

82. The assembly as recited in claim 81, wherein said particles of nanomagnetic material are comprised of atoms of cobalt and atoms of iron.

83. The assembly as recited in claim 80, wherein said first distinct atom is a radioactive cobalt atom.

85. The assembly as recited in claim 84, wherein said particles of nanomagnetic material are comprised of a fifth distinct atom.

109. The assembly as recited in claim 84, wherein said second distinct atom has a relative magnetic permeability of about 1.0.

110. The assembly as recited in claim 109, wherein said second distinct atom is an atom selected from the group consisting of aluminum, antimony, barium, beryllium, boron, bismuth, calcium, gallium, germanium, gold, indium, lead, magnesium, palladium, platinum, silicon, silver, strontium, tantalum, tin, titanium, tungsten, yttrium, zirconium, magnesium, and zinc.

111. The assembly as recited in claim 109, wherein said third distinct atom is an atom selected from the group consisting of argon, bromine, carbon, chlorine, fluorine, helium, helium, hydrogen, iodine, krypton, oxygen, neon, nitrogen, phosphorus, sulfur, and xenon.

112. The assembly as recited in claim 110, wherein said third distinct atom is nitrogen.

113. The assembly as recited in claim 112, wherein said nanomagnetic particles are represented by the formula A_xB_yC_z, wherein A is said first distinct atom, B is said second distinct atom, C is said third distinct atom, and x+y+z is equal to 1.

114. The assembly as recited in claim 112, wherein said nanomagnetic particles are comprised of atoms of oxygen.