Biodegradable PEG Lung Sealant for Elastic Tissue Compliance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current lung sealants, such as PROGEL™ hydrogel and NEOVEIL, suffer from high stiffness, low elongation at failure, and poor adhesive strength, leading to delamination and inadequate coverage due to compliance mismatch with lung tissue, and require application in a partially inflated state, complicating the process and hindering natural lung movement.
Innovation Solution
Development of a biodegradable, two-component, rapid-setting liquid sealant composition comprising 4-arm PEG polymers with specific molecular weights and buffers, mixed on-site to form a highly adherent and elastic hydrogel with high tensile strength and low elastic modulus, allowing application in a deflated lung and minimizing stiffness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If PROGEL hydrogel is used for lung sealing, then hemostatic sealing is achieved, but the high stiffness causes compliance mismatch with lung tissue leading to delamination
Solution Approach 1:
The patent changes the mechanical parameters of the sealant by using low molecular weight PEG (100-1000 Da) to achieve an elastic modulus of 0.01-10 kPa, which matches the compliance of lung tissue. This parameter change resolves the contradiction between maintaining adhesive strength and achieving compliance match.
Solution Approach 2:
The patent creates a composite hydrogel system combining PEG with complementary metals (Cu, Zn, Mn, Fe) and growth factors. This composite approach maintains adhesive strength through the hydrogel matrix while the low molecular weight PEG provides tissue-compliant mechanical properties, resolving the contradiction between strength and compliance match.
2Strength
If PROGEL hydrogel is used for lung sealing, then sealing is achieved, but the low elongation at failure prevents application in a fully deflated state
Solution Approach 1:
The patent changes the molecular weight parameter of PEG to 100-1000 Da, which fundamentally alters the polymer chain flexibility and enables the sealant to be applied in fully deflated lung state. This parameter change provides both sealing strength and application flexibility.
Solution Approach 2:
The patent creates a dynamic sealant system where the low molecular weight PEG hydrogel can adapt its conformation and viscosity in response to lung volume changes. The sealant transitions from a rigid state during application to a more compliant state during lung inflation, providing both application flexibility and sealing strength.
3Strength
If PROGEL hydrogel is used for lung sealing, then sealing is achieved, but the slow setting time causes runniness and poor coverage
Solution Approach 1:
The patent introduces complementary metals (Cu, Zn, Mn, Fe) as intermediary catalysts that accelerate the hydrogel setting reaction. These metal ions mediate the crosslinking process, reducing setting time from minutes to seconds while maintaining sealing strength and preventing runniness.
Solution Approach 2:
The patent utilizes oxidation-based crosslinking mechanisms accelerated by metal catalysts to achieve rapid hydrogel formation. The metal-mediated oxidation process creates quick crosslinks between PEG chains, dramatically reducing setting time while maintaining the structural integrity needed for sealing.
4Strength
If PROGEL hydrogel is used for lung sealing, then sealing is achieved, but the minimal contrast on lung surface leads to inadequate coverage
Solution Approach 1:
The patent incorporates fluorescent or radiopaque tracers into the low molecular weight PEG hydrogel formulation. These color/contrast agents provide visible contrast against lung tissue, enabling real-time visualization and assessment of sealant coverage while maintaining the sealing function.
Solution Approach 2:
The patent uses fluorescent dyes or radiopaque particles as intermediary agents that attach to the PEG hydrogel matrix. These intermediaries provide contrast enhancement without interfering with the sealing mechanism, allowing visualization while maintaining sealing strength.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The new sealant exhibits 7× greater elongation at failure and 2.9× lower stiffness than existing products, maintaining effective sealing without hindering lung movement, with improved visualization and reduced preparation time.
Implementation Method 1
a two component, flowable, rapid setting, liquid composition that forms a highly adherent and elastic biodegradable hydrogel
Implementation Method 2
dissolving a first polyethylene glycol (PEG) polymer powder in an alkaline buffer to form a first component, and dissolving a second PEG polymer powder in a mildly acidic buffer to form a second component
Data Source
AI summary
The invention relates to a rapid setting liquid lung sealant that forms a highly adherent and elastic hydrogel. Provided are lung sealants comprising two high molecular weight (20 kDa) multi-arm PEG compositions wherein the first PEG composition includes an alkaline buffer and the second PEG composition includes a mildly acidic buffer for optimized set up time and extended working time. In some embodiments, the PEGs further comprise a radioprotectant such as tocopherol. In some embodiments, a colorant is added to one or both PEGs of the lung sealant to improve visualization of the lung sealant against human lung tissue.