Ionizable Lipid Nanoparticles With pH-Switched Charge for Nucleic Acid Loading
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing lipid-based nanoparticles for therapeutic and diagnostic compounds face challenges in effectively loading active agents like nucleic acids due to toxicity and poor biodistribution, particularly with positively charged lipids that adhere to cells and tissues.
Innovation Solution
Development of ionizable lipids that change charge state with pH, allowing efficient loading at low pH and reducing toxicity at physiological pH, formulated into nanoparticles for improved biodistribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If positively charged lipids are used to load nucleic acids, then loading efficiency is improved, but toxicity increases and biodistribution deteriorates
Solution Approach 1:
The lipid is designed to dynamically change its charge state in response to pH changes. At low pH (endosomal environment), the lipid is positively charged to facilitate nucleic acid loading and endosomal escape. At physiological pH (7.4), the lipid transitions to a neutral state to reduce toxicity and improve biodistribution. This dynamic charge switching resolves the contradiction between loading efficiency and toxicity.
Solution Approach 2:
The invention changes the pH parameter as a trigger for lipid charge state transition. By incorporating ionizable groups with pKa values tuned to transition around physiological pH, the lipid automatically switches from charged (at low pH for loading) to neutral (at pH 7.4 for circulation), thereby resolving the contradiction between effective loading and reduced toxicity.
2Manufacturing precision
If positively charged lipids are used to load nucleic acids, then loading efficiency is improved, but biodistribution deteriorates due to cell and tissue adhesion
Solution Approach 1:
The lipid dynamically switches from a positively charged state (at low pH during loading and endosomal escape) to a neutral state (at physiological pH during circulation and tissue distribution). This dynamic transition prevents non-specific cell and tissue adhesion while maintaining effective nucleic acid loading, thereby improving biodistribution without sacrificing loading efficiency.
Solution Approach 2:
The invention utilizes pH parameter changes to control lipid charge state. The ionizable groups are designed with pKa values that enable transition from charged to neutral as pH increases from endosomal levels to physiological levels, resolving the contradiction between loading efficiency and biodistribution by reducing adhesion during circulation.
3Manufacturing precision
If ionizable lipids are designed to be positive at low pH for loading, then loading efficiency is improved, but complexity of lipid structure increases
Solution Approach 1:
The invention incorporates ionizable functional groups (such as secondary amines, tertiary amines, or other pH-sensitive groups) into the lipid structure that automatically change charge state with pH. This parameter-based control mechanism achieves the desired charge switching behavior with relatively simple structural modifications, balancing loading efficiency with manageable structural complexity.
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
Enhances drug delivery by providing new compositions that improve loading efficiency and reduce toxicity, ensuring targeted delivery of therapeutic and diagnostic agents.
Implementation Method 1
ionizable lipids that are charged at one pH and neutral at another. In particular, ionizable lipids that are positive at low pH (allowing for efficient loading) and neutral at physiological pH (lessening toxicity and improving biodistribution) are highly sought.
Data Source
AI summary
One or more ionizable lipid(s) and lipid nanoparticles comprising same are provided. Pharmaceutical compositions comprising the lipid nanoparticles encapsulating an active agent are also provided.