DE3752274T2 - Dichte sternförmige Polymere zur Kalibrierung/Klassierung von Submikron-Öffnungen - Google Patents

Dichte sternförmige Polymere zur Kalibrierung/Klassierung von Submikron-Öffnungen

Info

Publication number
DE3752274T2
DE3752274T2 DE3752274T DE3752274T DE3752274T2 DE 3752274 T2 DE3752274 T2 DE 3752274T2 DE 3752274 T DE3752274 T DE 3752274T DE 3752274 T DE3752274 T DE 3752274T DE 3752274 T2 DE3752274 T2 DE 3752274T2
Authority
DE
Germany
Prior art keywords
calibration
classification
shaped polymers
dense star
submicron openings
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
DE3752274T
Other languages
English (en)
Other versions
DE3752274D1 (de
Inventor
Donald A Tomalia
Larry R Wilson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dendritic Nanotechnologies Inc
Original Assignee
Dow Chemical Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dow Chemical Co filed Critical Dow Chemical Co
Publication of DE3752274D1 publication Critical patent/DE3752274D1/de
Application granted granted Critical
Publication of DE3752274T2 publication Critical patent/DE3752274T2/de
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G83/00Macromolecular compounds not provided for in groups C08G2/00 - C08G81/00
    • C08G83/002Dendritic macromolecules
    • C08G83/003Dendrimers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D65/00Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
    • B01D65/10Testing of membranes or membrane apparatus; Detecting or repairing leaks
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08CTREATMENT OR CHEMICAL MODIFICATION OF RUBBERS
    • C08C19/00Chemical modification of rubber
    • C08C19/30Addition of a reagent which reacts with a hetero atom or a group containing hetero atoms of the macromolecule
    • C08C19/42Addition of a reagent which reacts with a hetero atom or a group containing hetero atoms of the macromolecule reacting with metals or metal-containing groups
    • C08C19/44Addition of a reagent which reacts with a hetero atom or a group containing hetero atoms of the macromolecule reacting with metals or metal-containing groups of polymers containing metal atoms exclusively at one or both ends of the skeleton
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G69/00Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
    • C08G69/44Polyester-amides
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G73/00Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
    • C08G73/02Polyamines
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N15/00Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
    • G01N15/08Investigating permeability, pore-volume, or surface area of porous materials
    • G01N15/088Investigating volume, surface area, size or distribution of pores; Porosimetry
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S424/00Drug, bio-affecting and body treating compositions
    • Y10S424/16Dendrimers and dendritic polymers

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Biochemistry (AREA)
  • Immunology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Dispersion Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Pathology (AREA)
  • General Chemical & Material Sciences (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Apparatus Associated With Microorganisms And Enzymes (AREA)
  • Manufacture Of Macromolecular Shaped Articles (AREA)
DE3752274T 1986-05-30 1987-05-29 Dichte sternförmige Polymere zur Kalibrierung/Klassierung von Submikron-Öffnungen Expired - Fee Related DE3752274T2 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US06/868,979 US4713975A (en) 1986-05-30 1986-05-30 Dense star polymers for calibrating/characterizing sub-micron apertures

Publications (2)

Publication Number Publication Date
DE3752274D1 DE3752274D1 (de) 1999-06-17
DE3752274T2 true DE3752274T2 (de) 1999-09-09

Family

ID=25352696

Family Applications (2)

Application Number Title Priority Date Filing Date
DE3752274T Expired - Fee Related DE3752274T2 (de) 1986-05-30 1987-05-29 Dichte sternförmige Polymere zur Kalibrierung/Klassierung von Submikron-Öffnungen
DE3751550T Expired - Fee Related DE3751550T2 (de) 1986-05-30 1987-05-29 Verfahren zur Kalibrierung/Klassierung von Submikron-öffnungen.

Family Applications After (1)

Application Number Title Priority Date Filing Date
DE3751550T Expired - Fee Related DE3751550T2 (de) 1986-05-30 1987-05-29 Verfahren zur Kalibrierung/Klassierung von Submikron-öffnungen.

Country Status (8)

Country Link
US (1) US4713975A (de)
EP (2) EP0566165B1 (de)
CN (1) CN1010131B (de)
AU (1) AU610499B2 (de)
CA (1) CA1275750C (de)
DE (2) DE3752274T2 (de)
IL (1) IL82661A (de)
MY (1) MY101231A (de)

Families Citing this family (72)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995024221A1 (en) * 1986-08-18 1995-09-14 The Dow Chemical Company Bioactive and/or targeted dendrimer conjugates
US5560929A (en) * 1986-08-18 1996-10-01 The Dow Chemical Company Structured copolymers and their use as absorbents, gels and carriers of metal ions
US5527524A (en) * 1986-08-18 1996-06-18 The Dow Chemical Company Dense star polymer conjugates
DE3636481A1 (de) * 1986-10-27 1988-05-05 Altenburger Electronic Gmbh Verfahren zur herstellung von mikropruefkoerpern zur porengroessenmessung in ultra- und mikrofiltern sowie hiernach hergestellte pruefkoerper
CA2028804C (en) * 1989-11-21 2000-06-20 Howard J. Buttery Biomosaic polymers and method for preparing same
US5631329A (en) * 1990-08-27 1997-05-20 Dendritech, Inc. Process for producing hyper-comb-branched polymers
US5773527A (en) * 1990-08-27 1998-06-30 Dendritech, Inc. Non-crosslinked, polybranched polymers
US5871713A (en) * 1991-12-04 1999-02-16 Guerbet S.A. Macromolecular polyamine iodine-containing compound, process for its preparation and its use as a contrast agent
US6113946A (en) * 1992-04-03 2000-09-05 The Regents Of The University Of California Self-assembling polynucleotide delivery system comprising dendrimer polycations
CA2143053A1 (en) * 1994-03-14 1995-09-15 Jorge G. Tezon Induction of the acrosome reaction to evaluate the fertilization capability of mammalian sperm
US5650101A (en) * 1994-07-25 1997-07-22 University Of South Florida Lock and key micelles
US5863919A (en) * 1994-07-25 1999-01-26 University Of South Florida Lock and key micelles and monomer building blocks therefor
US5449519C1 (en) 1994-08-09 2001-05-01 Revlon Consumer Prod Corp Cosmetic compositions having keratolytic and anti-acne activity
FR2761691B1 (fr) 1997-04-03 1999-05-14 Oreal Polymeres a fonction terminale thiol
US5902863A (en) * 1997-07-21 1999-05-11 Dow Corning Corporation Dendrimer-based networks containing lyophilic organosilicon and hydrophilic polyamidoamine nanoscopic domains
DE19732775A1 (de) * 1997-07-30 1999-02-04 Henkel Ecolab Gmbh & Co Ohg Verfahren zur Qualitätsüberprüfung von Membranen
US6395804B1 (en) 1998-12-18 2002-05-28 3M Innovative Properties Company Polyelectrolyte dispersants for hydrophobic particles in water-based systems
US6258896B1 (en) 1998-12-18 2001-07-10 3M Innovative Properties Company Dendritic polymer dispersants for hydrophobic particles in water-based systems
US6262207B1 (en) 1998-12-18 2001-07-17 3M Innovative Properties Company ABN dispersants for hydrophobic particles in water-based systems
CA2362994C (en) * 1999-02-16 2009-12-01 The Dow Chemical Company Core-shell tectodendrimers
US6077500A (en) * 1999-03-18 2000-06-20 Dow Corning Corporation High generation radially layered dendrimers
US6440405B1 (en) * 1999-06-07 2002-08-27 University Of Delaware Quaternary ammonium functionalized dendrimers and methods of use therefor
US6448337B1 (en) 1999-10-07 2002-09-10 3M Innovative Properties Company Pressure sensitive adhesives possessing high load bearing capability
US20020122782A1 (en) * 1999-10-15 2002-09-05 Gwen-Nelson Bichard Hair treatment system
US7067111B1 (en) * 1999-10-25 2006-06-27 Board Of Regents, University Of Texas System Ethylenedicysteine (EC)-drug conjugates, compositions and methods for tissue specific disease imaging
DE10016881B4 (de) * 2000-04-05 2006-06-01 Qiagen Gmbh Gezielte Transfektion von Zellen mittels biotinyliertem Dendrimer
US20040006036A1 (en) * 2000-04-12 2004-01-08 Gmr, A Delaware Corporation Silencing transcription by methylation
US6471968B1 (en) 2000-05-12 2002-10-29 Regents Of The University Of Michigan Multifunctional nanodevice platform
DK1286704T3 (da) 2000-06-02 2014-09-22 Univ Texas Ethylendicystein (EC)-glucose analoge konjugater
US6448301B1 (en) 2000-09-08 2002-09-10 3M Innovative Properties Company Crosslinkable polymeric compositions and use thereof
US7045283B2 (en) 2000-10-18 2006-05-16 The Regents Of The University Of California Methods of high-throughput screening for internalizing antibodies
KR100372908B1 (ko) * 2000-11-22 2003-02-15 광주과학기술원 용질의 특정분자량 부분제거율을 이용한 막공 크기분포측정방법 및 장치
CA2444383A1 (en) * 2001-04-26 2002-11-07 Board Of Regents, The University Of Texas System Therapeutic agent/ligand conjugate compositions, their methods of synthesis and use
US6635690B2 (en) 2001-06-19 2003-10-21 3M Innovative Properties Company Reactive oligomers
US7674850B2 (en) 2001-08-15 2010-03-09 3M Innovative Properties Company Hardenable self-supporting structures and methods
AU2002326950A1 (en) * 2001-09-19 2003-04-01 Pe Corporation (Ny) Membrane transportable fluorescent substrates
US7261875B2 (en) * 2001-12-21 2007-08-28 Board Of Regents, The University Of Texas System Dendritic poly (amino acid) carriers and methods of use
JP2006515835A (ja) * 2002-11-07 2006-06-08 ボード オブ リージェンツ, ザ ユニバーシティ オブ テキサス システム 組織特異的疾患のイメージングのための、エチレンジシステイン(ec)−薬物結合体、組成物、および方法
US20050040551A1 (en) 2003-08-19 2005-02-24 Biegler Robert M. Hardenable dental article and method of manufacturing the same
US7754500B2 (en) * 2003-11-21 2010-07-13 Anp Technologies, Inc. Asymmetrically branched polymer conjugates and microarray assays
US9050378B2 (en) * 2003-12-10 2015-06-09 Board Of Regents, The University Of Texas System N2S2 chelate-targeting ligand conjugates
US20090104119A1 (en) * 2004-08-25 2009-04-23 Majoros Istvan J Dendrimer Based Compositions And Methods Of Using The Same
WO2006102484A2 (en) * 2005-03-21 2006-09-28 Anp Technologies, Inc. Symmetrically branched polymer conjugates and microarray assays
US7960442B2 (en) 2005-04-20 2011-06-14 International Business Machines Corporation Nanoporous media templated from unsymmetrical amphiphilic porogens
US7482389B2 (en) * 2005-04-20 2009-01-27 International Business Machines Corporation Nanoporous media with lamellar structures
CA2606815C (en) 2005-05-02 2017-03-07 Anp Technologies, Inc. Polymer conjugate enhanced bioassays
CA2912259C (en) 2005-05-27 2020-04-28 Mark H. Schoenfisch Nitric oxide-releasing particles for nitric oxide therapeutics and biomedical applications
US20070041934A1 (en) * 2005-08-12 2007-02-22 Regents Of The University Of Michigan Dendrimer based compositions and methods of using the same
US8492098B2 (en) 2006-02-21 2013-07-23 The Trustees Of Tufts College Methods and arrays for target analyte detection and determination of reaction components that affect a reaction
US8758723B2 (en) 2006-04-19 2014-06-24 The Board Of Regents Of The University Of Texas System Compositions and methods for cellular imaging and therapy
EP2069054A1 (de) * 2006-08-30 2009-06-17 GE Healthcare Bio-Sciences Corp. System und verfahren zur charakterisierung von membranen und membranfiltriervorrichtungen
EP2073782B1 (de) * 2006-09-13 2011-07-20 3M Innovative Properties Company Dentalzusammensetzungen mit organogelatoren, produkte und verfahren
US10925977B2 (en) 2006-10-05 2021-02-23 Ceil>Point, LLC Efficient synthesis of chelators for nuclear imaging and radiotherapy: compositions and applications
US20090088376A1 (en) * 2007-04-19 2009-04-02 The Regents Of The University Of Michigan Dendrimer based compositions and methods of using the same
US8252834B2 (en) 2008-03-12 2012-08-28 The Regents Of The University Of Michigan Dendrimer conjugates
US8889635B2 (en) 2008-09-30 2014-11-18 The Regents Of The University Of Michigan Dendrimer conjugates
US9017644B2 (en) 2008-11-07 2015-04-28 The Regents Of The University Of Michigan Methods of treating autoimmune disorders and/or inflammatory disorders
DK2467173T3 (da) 2009-08-21 2019-07-29 Novan Inc Sårbandager, fremgangsmåder til anvendelse heraf og fremgangsmåder til dannelse deraf
EP4249001A3 (de) 2009-08-21 2023-11-29 Novan, Inc. Topische gele
US8945508B2 (en) 2009-10-13 2015-02-03 The Regents Of The University Of Michigan Dendrimer compositions and methods of synthesis
WO2011059586A2 (en) 2009-10-30 2011-05-19 The Regents Of The University Of Michigan Multifunctional small molecules
US8591876B2 (en) 2010-12-15 2013-11-26 Novan, Inc. Methods of decreasing sebum production in the skin
KR102007997B1 (ko) 2011-02-07 2019-08-07 라이프 테크놀로지스 코포레이션 감수성 화합물을 안정화시키는 조성물 및 방법
EP2681286B1 (de) 2011-02-28 2018-08-15 Novan, Inc. Stickoxid-freisetzende s-nitrosothiol-modifizierte kieselsäureteilchen und verfahren zu ihrer herstellung
US9402911B2 (en) 2011-12-08 2016-08-02 The Regents Of The University Of Michigan Multifunctional small molecules
WO2013177197A1 (en) 2012-05-21 2013-11-28 University Of Miami Dendrimer conjugates for coating cells
US9603953B2 (en) 2014-01-13 2017-03-28 Guanghua YANG Dendrimer compositions, methods of synthesis, and uses thereof
CN107531900A (zh) 2015-03-06 2018-01-02 北卡罗来纳-查佩尔山大学 聚合物二甲双胍和其作为治疗剂和作为递送载体的用途
US9828626B2 (en) 2015-07-10 2017-11-28 Pall Corporation Dendrimer conjugates for determining membrane retention level and/or pore structure
JP2017148724A (ja) * 2016-02-24 2017-08-31 国立大学法人神戸大学 正浸透膜分離で使用するドロー溶質およびその製造方法
CN106124387A (zh) * 2016-09-18 2016-11-16 天津市中海科技实业总公司 一种超滤膜截留率的测试方法
PL239642B1 (pl) 2018-08-16 2021-12-20 Pomorski Univ Medyczny W Szczecinie Kompozycja do doszklistkowego podawania białka leczniczego

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2693706A (en) * 1951-09-05 1954-11-09 Frank G Carpenter Method of and graded spheres for calibration of sieves
US3392573A (en) * 1966-09-07 1968-07-16 Atomic Energy Commission Usa Aerosol filter test device
US3455146A (en) * 1967-06-06 1969-07-15 Du Pont Method and apparatus for determining filtrability time
US3478601A (en) * 1968-07-26 1969-11-18 Walker Mfg Co Filter test apparatus
US3832423A (en) * 1971-02-22 1974-08-27 Cpc International Inc Chemically joined, phase separated graft copolymers having hydrocarbon polymeric backbones
US3985830B1 (en) * 1974-07-15 1998-03-03 Univ Akron Star polymers and process for the preparation thereof
US4409368A (en) * 1981-07-13 1983-10-11 The General Tire & Rubber Company Preparation of star polymers
US4507466A (en) * 1983-01-07 1985-03-26 The Dow Chemical Corporation Dense star polymers having core, core branches, terminal groups
US4558120A (en) * 1983-01-07 1985-12-10 The Dow Chemical Company Dense star polymer
US4568737A (en) * 1983-01-07 1986-02-04 The Dow Chemical Company Dense star polymers and dendrimers
ATE48005T1 (de) * 1984-07-05 1989-12-15 Du Pont Sternfoermige akrylpolymere.
US4586376A (en) * 1984-09-25 1986-05-06 Union Oil Company Of California Determining the effect of fluid flow through permeable media
US4599400A (en) * 1984-12-18 1986-07-08 The Dow Chemical Company Star/comb-branched polyamide
US4648261A (en) * 1985-11-12 1987-03-10 Exxon Production Research Co. Method for determining physical properties of a porous sample using capillary pressure measurement

Also Published As

Publication number Publication date
EP0566165A1 (de) 1993-10-20
DE3751550T2 (de) 1996-03-07
IL82661A0 (en) 1987-11-30
CN87104698A (zh) 1988-08-24
AU7332687A (en) 1987-12-03
EP0247629B1 (de) 1995-10-04
EP0247629A2 (de) 1987-12-02
MY101231A (en) 1991-08-17
IL82661A (en) 1991-05-12
CA1275750C (en) 1990-10-30
EP0566165B1 (de) 1999-05-12
CN1010131B (zh) 1990-10-24
EP0247629A3 (de) 1991-06-05
AU610499B2 (en) 1991-05-23
US4713975A (en) 1987-12-22
DE3752274D1 (de) 1999-06-17
DE3751550D1 (de) 1995-11-09

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Owner name: DENDRITIC NANOTECHNOLOGIES, INC., MT. PLEASANT, MI

8339 Ceased/non-payment of the annual fee