High-Tg Polyesteramide Copolymers for Stable Drug Release
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing degradable polymers for drug delivery face challenges in achieving desired release rates and compatibility with bioactive agents, particularly when exposed to aqueous environments, with many polymers having wet glass transition temperatures below body temperature, leading to inconsistent release profiles and incompatibility with certain drugs.
Innovation Solution
Development of a random copolymer with a glass transition temperature above body temperature, formulated to maintain structural integrity in aqueous environments, ensuring consistent and extended release of bioactive agents, with improved compatibility and uniform daily dose delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If known polyesteramide polymers are used for drug delivery, then compatibility with certain APIs is improved, but the polymer becomes plasticized in aqueous environment resulting in wet Tg below body temperature
Solution Approach 1:
The patent modifies the chemical structure parameters of polyesteramide polymers by incorporating specific monomer units (hydroxyethyl methacrylate, glycidyl methacrylate, or ethyl glycidyl methacrylate) at controlled ratios (0.1-10 mol%) to change the polymer's thermal properties. This structural parameter change raises the wet Tg above body temperature while preserving API compatibility, resolving the contradiction between compatibility and temperature stability in aqueous environments
Solution Approach 2:
The patent creates a composite polymer system by combining traditional polyesteramide backbone with specific functional monomer units (HEMA, GM, or EGM) as copolymer components. This composite structure integrates the beneficial properties of both polymer components: the polyesteramide provides biocompatibility and drug compatibility, while the functional monomers provide thermal stability in aqueous environments, thereby resolving the contradiction
2Stability of the object's composition
If polymers with wet Tg above body temperature are used, then structural integrity in aqueous environment is improved, but compatibility with certain drugs deteriorates
Solution Approach 1:
The patent precisely adjusts the compositional parameters of the copolymer by controlling the ratio of polyesteramide units to functional monomer units (HEMA, GM, or EGM) within specific ranges (0.1-10 mol%). This parameter optimization ensures that the polymer maintains sufficient flexibility and drug compatibility while achieving the desired wet Tg above body temperature, thus resolving the contradiction between structural stability and drug compatibility
Solution Approach 2:
The patent introduces specific functional monomer units at localized positions within the polymer chain to achieve different local properties: the polyesteramide segments provide drug compatibility and biocompatibility, while the functional monomer segments (HEMA, GM, EGM) provide thermal stability. This local differentiation of polymer properties allows simultaneous achievement of both drug compatibility and structural integrity in aqueous environments
3Ease of operation
If degradable polymers are used for drug delivery, then no separate removal procedure is required, but achieving desired release rate and release duration becomes challenging
Solution Approach 1:
The patent changes the physical and chemical parameters of the polymer by incorporating functional monomers that modify degradation kinetics. The specific monomer units (HEMA, GM, EGM) alter the hydrolysis rate and crystallinity of the polyesteramide matrix, thereby controlling the release rate and duration of bioactive agents. This parameter modification enables achievement of desired release profiles (burst, zero-order, or sustained) while maintaining the advantage of no separate removal procedure
Solution Approach 2:
The functional monomer units (HEMA, GM, EGM) act as intermediary elements within the polymer matrix that mediate between the polyesteramide backbone and the bioactive agent. These intermediaries control the diffusion and degradation pathways, thereby regulating the release rate and duration. The intermediary monomers provide a controlled interface that enables predictable release profiles while maintaining the degradable polymer's advantage of eliminating separate removal procedures
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 random copolymer achieves controlled and extended release of bioactive agents, maintaining structural stability and compatibility with a wide range of drugs, including acid-sensitive agents, while providing improved implant morphology during degradation.
Implementation Method 1
the barrier properties when the polymer is below its glass transition temperature (Tg) differ greatly from the barrier properties when the polymer is above its Tg. Moreover, the polymer will be in the 'wet' state when present in the body's physiological fluid. Polymers typically have a lower wet Tg than a dry Tg.
Data Source
AI summary
Disclosed herein are polyesteramide random copolymers having high glass transition temperatures, methods of forming such polymers, devices, formulations, and medical devices containing such polymers, and methods of treating mammals suffering from various conditions using such polymers in combination with a bioactive agent. In an embodiment, the random copolymers may have a Tg above body temperature, about 37° C., and may achieve a longer release duration, different release kinetics, improved barrier properties, or other benefits over polymers with Tg below 37° C.