DE19514515A1 - Magnetisable iron oxide nano-particle dispersion with high saturation polarisation - Google Patents
Magnetisable iron oxide nano-particle dispersion with high saturation polarisationInfo
- Publication number
- DE19514515A1 DE19514515A1 DE19514515A DE19514515A DE19514515A1 DE 19514515 A1 DE19514515 A1 DE 19514515A1 DE 19514515 A DE19514515 A DE 19514515A DE 19514515 A DE19514515 A DE 19514515A DE 19514515 A1 DE19514515 A1 DE 19514515A1
- Authority
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- Germany
- Prior art keywords
- fatty alcohols
- magnetizable
- functionalized
- dispersions
- carboxy
- Prior art date
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- 239000006185 dispersion Substances 0.000 title claims abstract description 38
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 title description 16
- 239000002105 nanoparticle Substances 0.000 title 1
- 238000001179 sorption measurement Methods 0.000 claims abstract description 27
- 150000002191 fatty alcohols Chemical class 0.000 claims abstract description 25
- 239000002245 particle Substances 0.000 claims abstract description 23
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 16
- 235000014113 dietary fatty acids Nutrition 0.000 claims abstract description 13
- 239000000194 fatty acid Substances 0.000 claims abstract description 13
- 229930195729 fatty acid Natural products 0.000 claims abstract description 13
- 150000004665 fatty acids Chemical class 0.000 claims abstract description 12
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 claims abstract description 10
- 239000000203 mixture Substances 0.000 claims description 10
- 239000000243 solution Substances 0.000 claims description 7
- 238000000926 separation method Methods 0.000 claims description 6
- 239000000126 substance Substances 0.000 claims description 6
- 239000003792 electrolyte Substances 0.000 claims description 5
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 238000005406 washing Methods 0.000 claims description 4
- 229910006297 γ-Fe2O3 Inorganic materials 0.000 claims description 4
- 102000004169 proteins and genes Human genes 0.000 claims description 3
- 108090000623 proteins and genes Proteins 0.000 claims description 3
- 150000002505 iron Chemical class 0.000 claims description 2
- 238000000034 method Methods 0.000 claims description 2
- 230000008569 process Effects 0.000 claims description 2
- 239000012266 salt solution Substances 0.000 claims description 2
- 125000000217 alkyl group Chemical group 0.000 claims 1
- 125000004432 carbon atom Chemical group C* 0.000 claims 1
- 239000003054 catalyst Substances 0.000 claims 1
- 238000006555 catalytic reaction Methods 0.000 claims 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 claims 1
- 239000000696 magnetic material Substances 0.000 claims 1
- 238000013160 medical therapy Methods 0.000 claims 1
- 239000002994 raw material Substances 0.000 claims 1
- 229920006395 saturated elastomer Polymers 0.000 claims 1
- 150000004671 saturated fatty acids Chemical class 0.000 claims 1
- 235000003441 saturated fatty acids Nutrition 0.000 claims 1
- 239000004094 surface-active agent Substances 0.000 claims 1
- 150000004670 unsaturated fatty acids Chemical class 0.000 claims 1
- 235000021122 unsaturated fatty acids Nutrition 0.000 claims 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 abstract 1
- 238000004062 sedimentation Methods 0.000 description 10
- POULHZVOKOAJMA-UHFFFAOYSA-N dodecanoic acid Chemical compound CCCCCCCCCCCC(O)=O POULHZVOKOAJMA-UHFFFAOYSA-N 0.000 description 6
- 239000007788 liquid Substances 0.000 description 6
- 230000010287 polarization Effects 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 5
- 239000000908 ammonium hydroxide Substances 0.000 description 4
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical group Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 4
- TWJNQYPJQDRXPH-UHFFFAOYSA-N 2-cyanobenzohydrazide Chemical compound NNC(=O)C1=CC=CC=C1C#N TWJNQYPJQDRXPH-UHFFFAOYSA-N 0.000 description 3
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 3
- 239000005639 Lauric acid Substances 0.000 description 3
- 235000021360 Myristic acid Nutrition 0.000 description 3
- TUNFSRHWOTWDNC-UHFFFAOYSA-N Myristic acid Natural products CCCCCCCCCCCCCC(O)=O TUNFSRHWOTWDNC-UHFFFAOYSA-N 0.000 description 3
- 230000000975 bioactive effect Effects 0.000 description 3
- 150000007942 carboxylates Chemical class 0.000 description 3
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical class Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M potassium hydroxide Substances [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 3
- 108090000765 processed proteins & peptides Proteins 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- 150000003460 sulfonic acids Chemical class 0.000 description 3
- 229910021577 Iron(II) chloride Inorganic materials 0.000 description 2
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- 102000004190 Enzymes Human genes 0.000 description 1
- 108090000790 Enzymes Proteins 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 235000021355 Stearic acid Nutrition 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000005904 alkaline hydrolysis reaction Methods 0.000 description 1
- 150000001413 amino acids Chemical class 0.000 description 1
- 239000008346 aqueous phase Substances 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 230000032050 esterification Effects 0.000 description 1
- 238000005886 esterification reaction Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- -1 fatty acid esters Chemical class 0.000 description 1
- 238000005189 flocculation Methods 0.000 description 1
- 230000016615 flocculation Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 125000002485 formyl group Chemical class [H]C(*)=O 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 159000000014 iron salts Chemical class 0.000 description 1
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 1
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 description 1
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 1
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 239000011553 magnetic fluid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 1
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 1
- 150000003891 oxalate salts Chemical class 0.000 description 1
- 230000004962 physiological condition Effects 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 102000004196 processed proteins & peptides Human genes 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- HEMHJVSKTPXQMS-UHFFFAOYSA-M sodium hydroxide Substances [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 239000008117 stearic acid Substances 0.000 description 1
- 150000003871 sulfonates Chemical class 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 238000005809 transesterification reaction Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N11/00—Carrier-bound or immobilised enzymes; Carrier-bound or immobilised microbial cells; Preparation thereof
- C12N11/14—Enzymes or microbial cells immobilised on or in an inorganic carrier
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K41/00—Medicinal preparations obtained by treating materials with wave energy or particle radiation ; Therapies using these preparations
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K49/00—Preparations for testing in vivo
- A61K49/06—Nuclear magnetic resonance [NMR] contrast preparations; Magnetic resonance imaging [MRI] contrast preparations
- A61K49/18—Nuclear magnetic resonance [NMR] contrast preparations; Magnetic resonance imaging [MRI] contrast preparations characterised by a special physical form, e.g. emulsions, microcapsules, liposomes
- A61K49/1806—Suspensions, emulsions, colloids, dispersions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C1/00—Magnetic separation
- B03C1/005—Pretreatment specially adapted for magnetic separation
- B03C1/01—Pretreatment specially adapted for magnetic separation by addition of magnetic adjuvants
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/44—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of magnetic liquids, e.g. ferrofluids
- H01F1/445—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of magnetic liquids, e.g. ferrofluids the magnetic component being a compound, e.g. Fe3O4
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
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- Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Zoology (AREA)
- General Health & Medical Sciences (AREA)
- Wood Science & Technology (AREA)
- Genetics & Genomics (AREA)
- Inorganic Chemistry (AREA)
- Biochemistry (AREA)
- Epidemiology (AREA)
- Biomedical Technology (AREA)
- Biotechnology (AREA)
- Veterinary Medicine (AREA)
- Microbiology (AREA)
- Public Health (AREA)
- Animal Behavior & Ethology (AREA)
- General Engineering & Computer Science (AREA)
- Pharmacology & Pharmacy (AREA)
- Medicinal Chemistry (AREA)
- Power Engineering (AREA)
- Dispersion Chemistry (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Radiology & Medical Imaging (AREA)
- Colloid Chemistry (AREA)
- Soft Magnetic Materials (AREA)
Abstract
Description
Die Erfindung betrifft magnetisierbare Dispersionen aus feinverteilten, superparamagnetischen Teilchen in Wasser, deren Herstellung und Verwendung, bei denen die Teilchen ausschließlich oder hauptsächlich aus Fe₃O₄ und/oder γ-Fe₂O₃ bestehen, eine Größe von 5 bis 50 nm aufweisen und deren Oberflächen mit wenigstens einer monomolekularen ersten Adsorptionsschicht stabilisiert und mit wenigstens einer zweiten Adsorptionsschicht oberflächenaktiviert sind, wobei die erste Adsorptionsschicht aus Fettsäuren besteht.The invention relates to magnetizable dispersions from finely divided, superparamagnetic particles in water, its production and use, where the particles are exclusively or consist mainly of Fe₃O₄ and / or γ-Fe₂O₃, have a size of 5 to 50 nm and their Surfaces with at least one monomolecular first Adsorption layer stabilized and with at least one second adsorption layer are surface activated, wherein the first adsorption layer consists of fatty acids.
Magnetisierbare Teilchen im Größenbereich von 5 bis 50 nm sind thermodynamisch nicht stabil und neigen zur Agglomerisierung und Sedimentation in Flüssigkeiten. Bekanntlich lassen sich durch Modifizierung der Teilchenoberflächen mittels Chemisorption und/oder Adsorption organischer Moleküle, nachfolgend immer als Adsorption bezeichnet, in Abstimmung mit der Trägerflüssigkeit konzentrierte sedimentationsstabile, magnetisierbare Dispersionen herstellen, deren Sedimentationsneigung auch in niedrigviskosen Trägerflüssigkeiten wie Wasser oder bei starker Verdünnung gering ist.Magnetizable particles in the size range from 5 to 50 nm are not thermodynamically stable and tend for agglomeration and sedimentation in liquids. As is known, by modifying the Particle surfaces by means of chemisorption and / or Adsorption of organic molecules, hereinafter always as Adsorption, in coordination with the Carrier liquid concentrated sedimentation-stable, Produce magnetizable dispersions whose Sedimentation tendency even in low viscosity Carrier liquids such as water or when diluted heavily is low.
Es sind zahlreiche Zusammensetzungen und Herstellungsvarianten von wäßrigen, magnetisierbaren Dispersionen auf Eisenoxidbasis bekannt (US 4 094 804, US 4 208 294), bei denen die Eisenoxidteilchen der genannten Größenklasse eine äußere Adsorptionsschicht aus ethoxylierten Fettalkoholen, Fettsäuren oder Sulfonsäuren aufweisen.There are numerous compositions and manufacturing variants of aqueous, magnetizable dispersions based on iron oxide known (US 4 094 804, US 4 208 294), in which the Iron oxide particles of the size class mentioned an outer Adsorption layer made of ethoxylated fatty alcohols, fatty acids or have sulfonic acids.
Liegt beispielsweise die Teilchengröße zwischen 5 und 15 nm, und werden dafür geeignete Fettsäuren eingesetzt, ergeben sich dann außerordentlich sedimentationsstabile wäßrige Dispersionen, wenn ein pH-Wert vorliegt, der zur Bildung von Carboxylaten oder Sulfonaten führt. Ändert sich der pH-Wert, aus welchen Gründen auch immer, kann dies aufgrund der veränderten elektrostatischen Abstoßung und der unterschiedlich starken Ausbildung von Wasserstoffbrückenbindungen zwischen den modifizierten Teilchen sowie unterschiedlicher Löslichkeitseigenschaften zur reversiblen Beeinflussung der Sedimentationsstabilität führen. Dadurch ist die Möglichkeit der Flockung, der Entfernung der Trägerflüssigkeit, Redispergierung und der Aufkonzentrierung gegeben (SHIMOIIZAFA, J. u. a.: "Coagulation and Redispersion of Water Base Magnetic Fluid", J. Mining and Metallurgical Institute of Japan 93 (1977) 1068, S. 83 bis 86). For example, the particle size is between 5 and 15 nm, and suitable fatty acids are used for this, this results in extremely stable sedimentation aqueous dispersions, if a pH value is available which Formation of carboxylates or sulfonates leads. If the pH changes, for whatever reason, this can be due to the changed electrostatic Repulsion and the different degrees of training of Hydrogen bonds between the modified Particles and different solubility properties for reversibly influencing the sedimentation stability to lead. This creates the possibility of flocculation Removal of the carrier liquid, redispersion and Concentration given (SHIMOIIZAFA, J. et al .: "Coagulation and Redispersion of Water Base Magnetic Fluid ", J. Mining and Metallurgical Institute of Japan 93 (1977) 1068, pp. 83 to 86).
Bestimmte Anwendungen, wie die Wertstofftrennung in magnetisierbaren wäßrigen Dispersionen, erfordern neben superparamagnetischem Verhalten sehr hohe Sättigungspolarisationen (US 3 483 969). Das kann durch Eisenoxidteilchen mit hohem Fe₃O₄- und/oder γ-Fe₂O₃-Anteil realisiert werden, wenn die Teilchengröße bei 12 bis 20 nm liegt und eine hohe Sedimentationsstabilität erreicht wird. Die Sedimentationsstabilität, speziell in starken Magnetfeldgradienten, ist in hohem Maße auch von der Adsorptionsschichtdicke abhängig, die Ursache für die sterische Abstoßung der modifizierten Teilchen ist (R.E. ROSENSZWEIG, "Fluid dynamics and signs of magnetic liquids", Advances in electronics electron physics, Vol. 48 S. 108-111).Certain applications, such as recycling in magnetizable aqueous dispersions, in addition to superparamagnetic behavior very high Saturation polarizations (US 3,483,969). That can be done by Iron oxide particles with a high Fe₃O₄ and / or γ-Fe₂O₃ content can be realized if the particle size at 12 to 20 nm lies and a high sedimentation stability is reached. The sedimentation stability, especially in strong ones Magnetic field gradient, is to a large extent also from that Depending on the adsorption layer thickness, the cause of the is steric repulsion of the modified particles (R.E. ROSENSZWEIG, "Fluid dynamics and signs of magnetic liquids ", Advances in electronics electron physics, Vol. 48 pp. 108-111).
Die beschriebenen Moleküllängen einfacher geeigneter Fettsäuren (US 4 208 294) oder Sulfonsäuren (US 4 094 804) reichen für eine Langzeitstabilisierung von magnetisierbaren Dispersionen, die in technischen Trennanlagen für die Wertstofftrennung mit Teilchengrößen über 12 nm eingesetzt werden, nicht aus. Dazu wäre eine dickere Adsorptionsschicht, wie sie theoretisch durch längere Molekülketten erreicht werden könnten, notwendig. Mit längeren Fettsäuren wie beispielsweise Stearinsäure können keine wirkungsvollen Adsorptionsschichten an den Teilchen erzeugt werden, die zu geeigneten Dispersionen in Wasser führen (US 4 208 294).The described molecular lengths are more suitable Fatty acids (US 4,208,294) or sulfonic acids (US 4 094 804) are sufficient for long-term stabilization of magnetizable dispersions used in technical Separation plants for the separation of valuable materials with particle sizes above 12 nm are used. That would be one thicker adsorption layer, as theoretically by longer molecular chains could be achieved. With longer fatty acids such as stearic acid cannot apply effective adsorption layers the particles are generated, the appropriate dispersions lead in water (US 4 208 294).
Werden ethoxylierte Fettalkohole zur Bildung der äußeren Adsorptionsschicht eingesetzt, ergeben sich zwar ausreichend dicke Adsorptionsschichten, die zu sedimentations stabilen wäßrigen Dispersionen führen (US 4 094 804, DE 43 27 826), jedoch können diese nur unter teilweiser oder vollständiger Desorption der äußeren Adsorptionsschicht irreversibel geflockt werden. Die ethoxylierten Fettalkohole können nach Abtrennung des Flockulates dann nur sehr aufwendig zurückgewonnen werden.Are ethoxylated fatty alcohols to form the used outer adsorption layer, result sufficiently thick adsorption layers that too sedimentation stable aqueous dispersions (US 4 094 804, DE 43 27 826), but these can only with partial or complete desorption the outer adsorption layer is irreversibly flocculated will. The ethoxylated fatty alcohols can after Separation of the flocculate is then very complex be recovered.
Die Redispergierung der Eisenoxydteilchen ist nur durch eine erneute Adsorption von ethoxylierten Fettalkoholen möglich.The redispersion of the iron oxide particles is only possible through a new adsorption of ethoxylated fatty alcohols possible.
Derartige Dispersionen haben den Nachteil, daß sie sich ohne Änderung der physikalisch-chemischen Zusammensetzung nur durch Verdampfen aufkonzentrieren lassen.Such dispersions have the disadvantage that they itself without changing the physico-chemical composition only concentrate by evaporation.
Für einige medizinische Anwendungen wäßriger magnetisierbarer Eisenoxyddispersionen ist die Ankopplung bioaktiver Substanzen wie beispielsweise Antikörper oder Enzyme an die äußere Adsorptionsschicht erforderlich. Wenn die Teilchen durch eine Doppelschicht, aus Fettsäuren bzw. aktivierten Fettsäuren bestehend, stabilisiert sind, kann das über eine Ester- oder Peptidbildung, ggf. über den Zwischenschritt der Carbonylaktivierung erfolgen (JAKUBKE, H.-D. "Aminosäure, Peptide, Proteine", Akademie-Verlag Berlin 1982, 3. Auflage, S. 157 bis 179).Aqueous magnetizable for some medical applications Iron oxide dispersions are the coupling of bioactive substances such as antibodies or enzymes to the outside Adsorption layer required. If the particles are through a Double layer, from fatty acids or activated fatty acids existing, stabilized, can be via an ester or Peptide formation, possibly via the intermediate step of Carbonyl activation takes place (JAKUBKE, H.-D. "amino acid, Peptides, Proteins ", Akademie-Verlag Berlin 1982, 3rd edition, Pp. 157 to 179).
Besteht die äußere Adsorptionsschicht ausschließlich aus Fettsäuren oder Fettsäureestern, resultiert dann allerdings auch bei partieller Veresterung, Peptidbildung oder Umesterung nur eine sedimentationsstabile wäßrige Dispersion, wenn alkalische Bedingungen vorliegen, die zur Carboxylatbildung an den restlichen Carboxylgruppen führen. Allein diese Tatsache schränkt die Einsatzmöglichkeiten enorm ein. The outer adsorption layer only exists from fatty acids or fatty acid esters, then results however also with partial esterification, peptide formation or transesterification only a sedimentation stable aqueous Dispersion when there are alkaline conditions that lead to Lead carboxylate formation on the remaining carboxyl groups. This fact alone limits the possible uses enormously on.
Außerdem kann unter diesen Bedingungen eine teilweise alkalische Hydrolyse nicht verhindert werden, was zu aufwendigen pH-Einstellungen und Dispergierverfahren unmittelbar vor Gebrauch dieser Systeme führt.In addition, under these conditions, a partial alkaline hydrolysis cannot be prevented, leading to elaborate pH settings and dispersion processes leads immediately before using these systems.
Befinden sich in der äußeren Adsorptionsschicht Fettsäuren und aminofunktionalisierte oder ethoxylierte Fettalkohole und aminofunktionalisierte Verbindungen, ist zwar die Ankopplung bioaktiver Substanzen möglich, jedoch reicht diese Kombination nicht zur Erzielung einer ausreichenden Dispersionsstabilität in wäßriger Phase aus.There are fatty acids in the outer adsorption layer and amino functionalized or ethoxylated fatty alcohols and amino functionalized compounds, is the Coupling of bioactive substances possible, but sufficient this combination is not sufficient to achieve Dispersion stability in the aqueous phase.
Bei diesem Stand der Technik liegt der Erfindung die Aufgabe zugrunde, neue wäßrige magnetisierbare Dispersionen mit hoher Sättigungspolarisation zu schaffen, deren Sedimentationsstabilität sich reversibel durch pH-Änderung gestalten läßt und die die Ankopplung biologisch aktiver Substanzen unter physiologischen Bedingungen ermöglichen.In this prior art, the object of the invention based, new aqueous magnetizable dispersions to create with high saturation polarization whose Sedimentation stability is reversible due to pH change can be designed and the coupling biologically more active Enable substances under physiological conditions.
Diese Aufgabe wird erfindungsgemäß durch die in den Ansprüchen 1, 5, 10 bis 12 angegebenden Merkmale gelöst. Vorteilhafte Ausführungen der Erfindung sind in den weiteren Ansprüchen angegeben.This object is achieved by the in the Claims 1, 5, 10 to 12 specified features solved. Advantageous embodiments of the invention are in the specified further claims.
Überraschenderweise wurde gefunden, daß insbesondere bei Teilchengrößen unter 50 nm ein Gemisch aus Fettalkoholen und ethoxylierten Fettalkoholen und/oder carboxy- oder carboxylatfunktionalisierten ethoxylierten Fettalkoholen bzw. veresterten carboxyfunktionalisierten und/oder aldehydfunktionaliserten bzw. aminofunktionalisierten ethoxylierten Fettalkoholen als oberflächenaktive äußere Adsorptionsschicht besonders geeignet ist, die Dispersionsstabilität reversibel zu beeinflussen und zugleich auch eine Ankopplung bioaktiver Substanzen zu ermöglichen.Surprisingly, it was found that in particular a mixture of fatty alcohols for particle sizes below 50 nm and ethoxylated fatty alcohols and / or carboxy or carboxylate-functionalized ethoxylated fatty alcohols or esterified carboxy-functionalized and / or aldehyde functionalized or amino functionalized ethoxylated fatty alcohols as a surface-active outer Adsorption layer is particularly suitable, the Reversibly influencing dispersion stability and at the same time a coupling of bioactive substances to enable.
Der besondere Vorteil der Erfindung besteht darin, daß ökologisch und physiologisch unbedenkliche sowie für die Wertstoffsortierung und für die medizinisch/biologische Anwendung besser geeignete, magnetisierbare stabile Eisenoxyddispersionen zur Verfügung stehen, als es durch den Einsatz von Fettsäuren, Sulfonsäuren oder ethoxylierten Fettalkoholen möglich ist.The particular advantage of the invention is that ecologically and physiologically harmless as well as for the Sorting of recyclables and for medical / biological Application more suitable, magnetizable stable Iron oxide dispersions are available as is by the Use of fatty acids, sulfonic acids or ethoxylated Fatty alcohols is possible.
Die Herstellung der erfindungsgemäßen magnetisierbaren Dispersionen soll nachfolgend anhand von Beispielen näher erläutert werden.The production of the magnetizable according to the invention Dispersions are described below with the aid of examples are explained.
Als magnetisierbare Teilchen werden Eisenoxidgemische, welche zum größten Teil aus Fe₃O₄ und/oder γ-Fe₂O₃ bestehen, durch alkalische Fällung aus Eisensalzlösungen hergestellt. Geeignete Eisensalze sind Eisenchloride, -sulfate, -nitrate oder -oxalate. Die alkalische Komponente kann eine wäßrige Kalium-, Natrium-, Ammonium- oder Kalziumhydroxydlösung sein.Iron oxide mixtures, which are for the most part consist of Fe₃O₄ and / or γ-Fe₂O₃, produced by alkaline precipitation from iron salt solutions. Suitable iron salts are iron chlorides, sulfates and nitrates or oxalates. The alkaline component can be an aqueous one Potassium, sodium, ammonium or calcium hydroxide solution.
In eine Lösung, die aus 12 g Eisen(II)chlorid, 26 g Eisen(III)chlorid und 110 ml Wasser besteht, wird 50 ml konzentrierte Ammoniumhydroxydlösung innerhalb von 30 Sekunden unter Rühren gegeben. Dann wird 30 Minuten bei 70°C gerührt und durch Waschen mit Wasser die Elektrolyte entfernt.In a solution consisting of 12 g iron (II) chloride, 26 g There is iron (III) chloride and 110 ml of water 50 ml concentrated ammonium hydroxide solution within Given for 30 seconds with stirring. Then 30 minutes stirred at 70 ° C and the electrolytes by washing with water away.
2,3 g eines Laurinsäure/Myristinsäuregemisches (3 : 1) werden bei 70°C adsorbiert. Nach 20 Minuten werden 10 g AKYPO SOFT 100 (Handelsname der Chemischen Fabrik Chem-Y GmbH) bei 80°C adsorbiert. Danach wird die Dispersion 30 Minuten in der Zentrifuge bei 3000 g von gröberen Aggregaten gereinigt.2.3 g of a lauric acid / myristic acid mixture (3: 1) adsorbed at 70 ° C. After 20 minutes, 10 g AKYPO SOFT 100 (trade name of Chemische Fabrik Chem-Y GmbH) adsorbed at 80 ° C. After that the Dispersion in the centrifuge at 3000 g for 30 minutes coarser aggregates cleaned.
Die resultierende Dispersion besitzt eine Sättigungspolarisation von 22 mT (20°C). Im Basischen liegt die Dispersionsrate bei einem Magnetfeldgradienten von 5 mT/cm nach 30 Tagen unter 2 Prozent.The resulting dispersion has one Saturation polarization of 22 mT (20 ° C). Basically the dispersion rate with a magnetic field gradient of 5 mT / cm after 30 days under 2 percent.
Nach Ansäuern der verdünnten Dispersion auf einen pH-Wert von 5 sedimentieren die umhüllten Teilchen unter Einwirkung eines Magnetfeldgradienten von 5 mT/cm innerhalb von 20 Minuten. Danach wird die Trägerflüssigkeit abdekantiert, der pH-Wert auf mindestens 8,5 zurückgestellt und 10 Minuten bei 70°C gerührt. Das Produkt entspricht hinsichtlich Sedimentationsstabilität und Sättigungspolarisation wieder der konzentrierten Ausgangsdispersion.After acidifying the diluted dispersion to a pH of 5 sediment the coated particles under the influence of a Magnetic field gradients of 5 mT / cm within 20 minutes. The carrier liquid is then decanted, the pH reset to at least 8.5 and 10 minutes at 70 ° C touched. The product corresponds in terms of Sedimentation stability and saturation polarization again concentrated initial dispersion.
In 80 ml konzentrierte Ammoniumhydroxydlösung wird eine Lösung, die aus 20 g Eisen(II)sulfat, 25 g Eisen(III)sulfat und 250 ml Wasser besteht, innerhalb von 30 Sekunden unter Rühren gegeben. Dann wird 30 Minuten bei 70°C gerührt und durch Waschen mit Wasser die Elektrolyte entfernt.In 80 ml of concentrated ammonium hydroxide solution Solution consisting of 20 g iron (II) sulfate, 25 g iron (III) sulfate and 250 ml of water, within 30 seconds Stir given. Then is stirred at 70 ° C for 30 minutes and removed the electrolytes by washing with water.
3,5 g eines Laurinsäure/Myristinsäuregemisches (3 : 1) werden bei 70°C adsorbiert. Nach 20 Minuten wird mehrmals mit Wasser gewaschen. Anschließend werden 8,1 g MARLINAT CM 40 (Handelsname der Hüls AG) bei 80°C adsorbiert. Zur Carboxylatbildung wird 0,9 g KOH zugegeben und noch 10 Minuten gerührt. Danach wird die Dispersion 30 Minuten in der Zentrifuge bei 3000 g von gröberen Aggregaten gereinigt. Die resultierende Dispersion besitzt eine Sättigungspolarisation von 24 mT (20°C). Im Basischen liegt die Dispersionsrate bei einem Magnetfeldgradienten von 5 mT/cm nach 30 Tagen unter 3 Prozent.3.5 g of a lauric acid / myristic acid mixture (3: 1) adsorbed at 70 ° C. After 20 minutes, several times Washed water. Then 8.1 g of MARLINAT CM 40 (Trade name of Hüls AG) adsorbed at 80 ° C. For Carboxylate formation is added 0.9 g KOH and another 10 minutes touched. Then the dispersion is in the 30 minutes Centrifuge at 3000 g cleaned of coarser aggregates. The resulting dispersion has one Saturation polarization of 24 mT (20 ° C). Basically the dispersion rate with a magnetic field gradient of 5 mT / cm after 30 days under 3 percent.
In 50 ml konzentrierte Ammoniumhydroxydlösung wird eine Lösung, die aus 12 g Eisen(II)chlorid, 26 g Eisen(III)chlorid und 110 ml Wasser besteht, innerhalb von 30 Sekunden unter Rühren gegeben. Dann wird 60 Minuten bei 80°C gerührt und durch Waschen mit Wasser die Elektrolyte entfernt.In 50 ml of concentrated ammonium hydroxide solution Solution consisting of 12 g iron (II) chloride, 26 g iron (III) chloride and 110 ml of water exists within Given for 30 seconds with stirring. Then at 60 minutes Stirred 80 ° C and the electrolytes by washing with water away.
2,3 g eines Laurinsäure/Myristinsäuregemisches (3 : 1) werden bei 80°C adsorbiert. Nach 20 Minuten wird mehrmals mit Wasser, elektrolytfrei gewaschen. Anschließend werden ein Gemisch aus 4,6 g MARLIPAL 24/50 (Handelsname der Hüls AG) und 0,35 g MARLINAT CM 100 (Handelsname der Hüls AG) bei 80°C. Danach wird die Dispersion 30 Minuten in der Zentrifuge bei 3000 g von gröberen Aggregaten gereinigt. Die resultierende Dispersion besitzt eine Sättigungspolarisation von 20 mT (20°C). Im Basischen liegt die Dispersion bei einem Magnetfeldgradienten von 5 mT/cm nach 30 Tagen unter 3 Prozent.2.3 g of a lauric acid / myristic acid mixture (3: 1) adsorbed at 80 ° C. After 20 minutes, several times Water, washed free of electrolytes. Then be a Mixture of 4.6 g MARLIPAL 24/50 (trade name of Hüls AG) and 0.35 g MARLINAT CM 100 (trade name of Hüls AG) at 80 ° C. Then the dispersion is in the 30 minutes Centrifuge at 3000 g cleaned of coarser aggregates. The resulting dispersion has one Saturation polarization of 20 mT (20 ° C). Basically the dispersion with a magnetic field gradient of 5 mT / cm 30 days under 3 percent.
Claims (8)
R′= (CH₂)xCH₃, C(CH₃)₃ und
n = 5-17, m = 0-15, o = 1-2, x = 1-4.3. Magnetizable dispersions claim 1, characterized in that the second adsorption layer consists of a mixture of fatty alcohols and ethoxylated fatty alcohols and / or carboxy- and / or carboxylate-functionalized and / or esterified carboxy-functionalized and / or aldehyde- or amino-functionalized ethoxylated fatty alcohols, which consists of general formula CH₃ (CH₂) n O (CH₂CH₂O) m R, where R = H, (CH₂) o COOH, (CH₂) o COO - , (CH₂) o COOR ′, (CH₂) o CHO, (CH₂) o NH₂
R '= (CH₂) x CH₃, C (CH₃) ₃ and
n = 5-17, m = 0-15, o = 1-2, x = 1-4.
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| WO1999033072A1 (en) * | 1997-12-22 | 1999-07-01 | Mediport Kardiotechnik Gmbh | Magnetic liquid and method and device for the production thereof |
| JP2001276596A (en) * | 2000-04-04 | 2001-10-09 | Kao Corp | Aqueous dispersant for inorganic powder |
| EP1821323A1 (en) * | 2006-02-15 | 2007-08-22 | Atomic Energy Council - Institute of Nuclear Energy Research | Preparation method for oil-based magnetic fluid |
| US8408395B2 (en) | 2007-07-17 | 2013-04-02 | Basf Se | Process for the beneficiation of ores by means of hydrophobic surfaces |
| EP2612683A3 (en) * | 2003-04-15 | 2014-04-16 | Koninklijke Philips N.V. | Electro-physiologic contrast composition and method for manufacture. |
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| Publication number | Publication date |
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| DE19514515C2 (en) | 1997-03-20 |
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