Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-11471556-B2
Publication Date
2022-10-18
Expiration Date
Abstract
A method of production of a tissue sealing patch is disclosed. The method comprises casting a polymer film from a biocompatible polyethylene glycol-caprolactone-lactide triblock copolymer (PECALA); softening the polymer film; placing a powdered tissue sealant material on a surface of said polymer film; and, pressing said polymer film to at least partially incorporate the sealant material into said surface of said polymer film. In some embodiments of the invention, the polymer film is created by heating and evacuating a work surface; applying a solution of PECALA to said work surface; adjusting a polymer blade to a predetermined height above said work surface; spreading said solution of PECALA over said work surface with said polymer blade; and evaporating said solvent. The PECALA preferably comprises PEG-CL-LA units connected by urethane linkages, PEG having a molecular weight of between 3000 and 3500 amu, and a CL:LA:PEG ratio of 34:2:1.
Core Innovation
The invention relates to fibrinogen-based tissue adhesive patches and methods of producing them. A biocompatible polyurethane polymer is cast into a polymer film of a characterized thickness, and the polymer film is softened before use. Powdered tissue sealant material is then placed on a surface of the softened polymer film.
The polymer film is pressed such that at least a portion of the powdered tissue sealant material is at least partially incorporated into the surface of the polymer film. The pressing incorporates the powdered tissue sealant material into the surface to a depth between 20 μm and 60 μm, and this incorporation depth is presented as a critical feature for the resulting adhesive behavior.
The described polymer film materials are polyethylene glycol–polycaprolactone copolymers, polyethylene glycol–DL-lactide copolymers, and polyethylene glycol–polycaprolactone–DL-lactide copolymers. The document further specifies PECALA-type formulations for the polyurethane polymer film and powdered sealant materials that include fibrinogen and thrombin.
The invention addresses a need for tissue sealing patches that provide adhesive strength while controlling sealant distribution and polymer film degradation time. Degradation-time tuning is described based on hydrophilic/hydrophobic ratio and PECALA formulation, and the document also describes manufacturing via a vacuum drawdown/coater manufacturing route.
Claims Coverage
The independent claim covers a method of producing a tissue adhesive patch by casting, softening, placing a powdered tissue sealant material on a polymer film, and pressing to partially incorporate the powder into the film surface to a specified penetration depth of 20 μm to 60 μm. The claim set includes additional inventive features that refine the polyurethane copolymer chemistry and specify powdered sealant options and quantitative parameters for incorporation and loading.
Casting and softening a polyurethane film of selected PEG–PCL/DL-lactide copolymers
Casting a polymer film from a biocompatible polyurethane polymer selected from polyethylene glycol–polycaprolactone copolymers, polyethylene glycol–DL-lactide copolymers, and polyethylene glycol–polycaprolactone–DL-lactide copolymers, and softening the polymer film.
Pressing for partial powder incorporation to 20–60 μm depth
Pressing the polymer film until at least a portion of the powdered tissue sealant material is at least partially incorporated into the surface of the polymer film, wherein the pressing incorporates the powdered tissue sealant material into the surface to a depth between 20 μm and 60 μm.
Using a specific PECALA polyurethane copolymer chemistry
Using a biocompatible polymer that is a polyethylene glycol–polycaprolactone–DL-lactide copolymer with polyethylene glycol having molecular weight between 3000 and 3500, a polycaprolactone to lactide ratio of 34:2, and PEG–PCL–DL-lactide units connected by isocyanate linkages.
Employing a fibrinogen-based powdered tissue sealant with fibrinogen and thrombin limits
Selecting the powdered tissue sealant material from a fibrinogen sealant with fibrinogen and thrombin limits, or pig plasma proteins containing fibrinogen and thrombin.
Including CaCl2 in the fibrinogen powdered sealant
Using a powdered tissue sealant as a fibrinogen sealant containing specified maximum amounts of fibrinogen and thrombin and including CaCl2.
Limiting powdered sealant loading on the polymer film to 1–3 mg/cm2
Placing the powdered tissue sealant material on a polymer film by applying 1–3 mg/cm2 of the powdered tissue sealant material.
Using a 30–70 μm thickness powder layer before pressing
Placing a layer of powdered tissue sealant material of 30–70 μm thickness on a polymer film surface.
Across the independent claim and its dependents, the core inventive coverage is the casting and softening of a selected PEG-based polyurethane polymer film followed by pressing to partially incorporate powdered tissue sealant material into the film surface to a depth between 20 μm and 60 μm. Dependent claim refinements further constrain the polyurethane copolymer chemistry, specify fibrinogen-based powdered sealant material options, and impose quantitative parameters for sealant loading and powder layer thickness.
Stated Advantages
The invention addresses a need for tissue sealing patches that provide adhesive strength while controlling sealant distribution and polymer film degradation time.
Degradation-time tuning is described based on hydrophilic/hydrophobic ratio and PECALA formulation.
Reported examples span multiple degradation times.
Technical findings include evidence that the sealant is partially embedded at the film surface with no free powder.
Adhesive performance trends are associated with incorporation depth.
Reported dependence of adhesive force on incorporation depth.
Documented Applications
Tissue adhesive patches.
Tissue sealing patches.
Interested in licensing this patent?