Patents by Inventor Peter X. Ma

Peter X. Ma has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20030071383
    Abstract: A method for preparing a highly porous, high surface area non-degradable material, comprises the steps of mixing a non-degradable polymer with a solvent or mixture of solvents; gelling the mixture; and treating the gel under conditions whereby a substantially solvent free porous structure is created having a porosity greater than about 80%. The resultant material is mechanically strong and has an architecture comprising at least one of nano fibrous, micro fibrous, non fibrous, complex porous structure with nano fibrous architecture, and mixtures thereof.
    Type: Application
    Filed: October 16, 2002
    Publication date: April 17, 2003
    Inventor: Peter X. Ma
  • Publication number: 20030073158
    Abstract: A method for preparing a highly porous, high surface area degradable or partially degradable material. The method comprises the steps of mixing a degradable or partially degradable polymer with a mixed solvent comprising a first solvent and a second solvent, wherein the mixed solvent comprises a ratio higher than 1:1, first solvent to second solvent; gelling the mixture; and treating the gel under conditions whereby a substantially solvent free porous structure is created having a porosity greater than about 80%; wherein the material is mechanically strong and has a complex porous structure with nano fibrous architecture.
    Type: Application
    Filed: October 16, 2002
    Publication date: April 17, 2003
    Inventor: Peter X. Ma
  • Patent number: 6497902
    Abstract: Biocompatible hydrogels, for: scaffoldings for tissue engineering; cell encapsulation matrices; injectable bulking materials for cosmetic and functional restorations; controlled release matrices; gene delivery vehicles; immunoprotection matrices; immobilization materials; food additives; medical gels; conductive electrode gels; lubricious coatings; film forming creams; membranes; superabsorbents; hydrophilic coatings; and wound dressings. The hydrogels include: at least one water-soluble polymer/copolymer; and at least one slow and/or fast dissolving and/or releasing divalent and/or multivalent cation-containing compound. At least one of the monomers is an acid, and/or contains an acid group or a derivative thereof. Such monomer reacts with the cations to form a three-dimensional ionically crosslinked hydrogel composition.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: December 24, 2002
    Assignee: The Regents of the University of Michigan
    Inventor: Peter X. Ma
  • Publication number: 20020150753
    Abstract: The present invention discloses the design and fabrication of highly porous (up to 97%) scaffolds from biodegradable polymers with a novel phase-separation technique to generate controllable parallel array of micro-tubular architecture. The porosity, diameter of the micro-tubes, the tubular morphology and their orientation may be controlled by the polymer concentration, solvent system and temperature gradient. The mechanical properties of these scaffolds are anisotropic. Osteoblastic cells are seeded in these 3-D scaffolds and cultured in vitro. The cell distribution and the neo-tissue organization are guided by the micro-tubular architecture. The method has general applicability to a variety of polymers, therefore the degradation rate, cell-matrix interactions may be controlled by the chemical composition of the polymers and the incorporation of bioactive moieties. These micro-tubular scaffolds may be used to regenerate a variety of tissues with anisotropic architecture and properties.
    Type: Application
    Filed: January 25, 2002
    Publication date: October 17, 2002
    Inventors: Peter X. Ma, Ruiyun Zhang
  • Publication number: 20020058718
    Abstract: Methods and compositions are described that provide three dimensional porous matrices as structural templates for cells. The porous matrices of the present invention have desirable mechanical properties suitable to a variety of applications, including platforms for in vitro cell cultivation, implants for tissue and organ engineering, and materials suitable for chromatography and filtration.
    Type: Application
    Filed: August 27, 2001
    Publication date: May 16, 2002
    Applicant: The Regents of the University of Michigan
    Inventors: Peter X. Ma, Ruiyun Zhang
  • Publication number: 20020005600
    Abstract: 3-D biodegradable porous, polymer (natural or synthetic) scaffolds with well-controlled, interconnected pores, and method for forming the porous materials. Hydrophilic and/or hydrophobic porogen materials were fabricated into 3-D negative replicas of the desired macroporous architectures. Biodegradable polymers (PLLA and PLGA) were dissolved in a solvent and cast onto the negative replica. After dissolving/leaching out the porogen materials, a porous polymer scaffold was formed. The skeletal structure of PLLA foams consisted of small platelets or nano-fibers, while PLGA foams had homogeneous skeletal structure. To improve the cell seeding, distribution, mass transport, and new tissue organization and vascularization, 3-D macroporous architectures are built in the nano-fibrous matrices. The method tailors polymer scaffolds for a variety of potential tissue engineering applications due to the well-controlled architecture, inter-pore connectivity, and mechanical properties.
    Type: Application
    Filed: May 11, 2001
    Publication date: January 17, 2002
    Inventor: Peter X. Ma
  • Patent number: 6281257
    Abstract: Methods and compositions are described that provide three dimensional porous matrices as structural templates for cells. The porous matrices of the present invention have desirable mechanical properties suitable to a variety of applications, including platforms for in vitro cell cultivation, implants for tissue and organ engineering, and materials suitable for chromatography and filtration.
    Type: Grant
    Filed: April 16, 1999
    Date of Patent: August 28, 2001
    Assignee: The Regents of the University of Michigan
    Inventors: Peter X. Ma, Ruiyun Zhang
  • Patent number: 6146892
    Abstract: Methods and compositions are described that provide three-dimensional fibrillar matrices useful as, among other things, structural prosthetics and scaffolds for cells. The porous fibrillar matrices of the present invention have desirable mechanical properties suitable to a variety of applications, including platforms for in vitro cell cultivation, implants for tissue and organ engineering, implants as tendon and facia prosthetics, and product packaging.
    Type: Grant
    Filed: September 28, 1998
    Date of Patent: November 14, 2000
    Assignee: The Regents of the University of Michigan
    Inventors: Peter X. Ma, Ruiyun Zhang