Branched Degradable PEG Binders Balance Half-Life and Vacuolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bio-related substances modified with high-molecular-weight polyethylene glycol derivatives face issues of vacuole formation in cells and insufficient blood half-life, particularly in long-term treatments, necessitating a degradable polyethylene glycol derivative that maintains stability in blood and prevents vacuolation.
Innovation Solution
A bio-related substance bonded to a branched and degradable polyethylene glycol derivative with an oligopeptide structure centered on glutamic acid, designed to be stable in blood and degrade intracellularly, suppressing vacuole formation while maintaining extended half-life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of moving object
If high-molecular-weight polyethylene glycol (molecular weight 40,000 or more) is used to modify bio-related substances, then the blood half-life is significantly extended, but vacuole formation occurs in cells of certain tissues
Solution Approach 1:
The polyethylene glycol chain is segmented by introducing degradable linkages (peptide bonds, ester bonds, or disulfide bonds) at regular intervals along the polymer backbone. This segmentation allows the high-molecular-weight PEG to be broken down into smaller fragments that can be excreted via renal filtration, preventing vacuole formation while maintaining the extended blood half-life benefit of the intact high-molecular-weight structure during circulation
Solution Approach 2:
The invention changes the chemical parameter of polyethylene glycol from non-degradable to degradable by incorporating hydrolyzable or reducible bonds into the polymer chain. This parameter change enables the PEG to transition from a persistent structure that causes vacuolization to a transient structure that degrades into excretable fragments, while the overall molecular weight and blood half-life extending properties are preserved during the circulation period
2Object-affected harmful factors
If the molecular weight of polyethylene glycol is reduced to suppress vacuole formation, then vacuole generation is suppressed, but the blood half-life of bio-related substances cannot be improved sufficiently
Solution Approach 1:
Rather than reducing the overall molecular weight of PEG, the invention segments the high-molecular-weight PEG chain into degradable units that maintain the high molecular weight during circulation (providing extended half-life) but can be cleaved into low-molecular-weight fragments (preventing vacuolization). The segmentation allows the system to have both high molecular weight benefits and low molecular weight safety profiles at different stages
Solution Approach 2:
The invention introduces dynamic character to the PEG structure by incorporating bonds that can change from intact to cleaved states. The PEG transitions from a stable high-molecular-weight structure in blood (providing half-life extension) to a degraded low-molecular-weight structure in cells (preventing vacuolization). This dynamic transformation allows the system to adapt its molecular weight profile based on the physiological environment
3Quantity of substance
If polyethylene glycol is used to modify bio-related substances, then solubility of hardly water-soluble drugs is improved, but long-term administration at high doses leads to vacuole formation in tissues
Solution Approach 1:
The invention changes the degradation parameter of PEG from non-degradable to degradable by incorporating hydrolyzable bonds (ester, peptide) or reducible bonds (disulfide) into the polymer chain. This parameter change enables the PEG to maintain its solubility-enhancing properties during circulation while preventing long-term accumulation and vacuolization through controlled degradation into excretable fragments
Solution Approach 2:
The degradable bonds in the PEG chain act as intermediaries that facilitate the transition from high-molecular-weight intact PEG (which provides solubility enhancement) to low-molecular-weight degraded fragments (which prevent vacuolization). These intermediary bonds allow the system to achieve both solubility improvement and tissue safety by mediating the transformation between the two states
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 solution provides a bio-related substance with equivalent blood half-life to conventional derivatives and prevents vacuole formation by ensuring uniform degradation products, enhancing stability and efficacy in long-term treatments.
Implementation Method 1
a bio-related substance bonded to a branched and degradable polyethylene glycol derivative with an oligopeptide structure centered on glutamic acid, designed to be stable in blood and degrade intracellularly
Data Source
AI summary
A bio-related substance bonded to a branched and degradable polyethylene glycol derivative that is degraded in the cells represented by the following formula (A):wherein each symbol is as defined in the present specification, is provided by the present invention.