Dynamic Release from Acetalated Dextran Nanoparticles for Precision Therapy of Inflammation

Area of Science:

• Biomaterials Science
• Nanotechnology
• Drug Delivery

Background:

• Polymer nanoparticles (NPs) can be engineered to respond to specific physiological conditions for targeted therapeutic delivery.
• Local pH changes, particularly decreases in inflammatory microenvironments, can be used as triggers for drug release.
• Existing drug delivery systems (DDS) often lack the ability to autonomously control both drug release (ON) and cessation (OFF).

Purpose of the Study:

• To systematically optimize acetalated dextran (AcDex) nanoparticle composition for precise, pH-responsive drug release.
• To develop a DDS capable of autonomous ON/OFF drug release switching based on dynamic pH fluctuations.
• To evaluate the performance of mixed AcDex NPs in response to biologically relevant pH changes.

Main Methods:

• Systematic optimization of acetalated dextran (AcDex) polymer mixing ratios to create mixed NPs.
• Testing NP cargo release profiles across a pH range from 7.4 to 6.0.
• Evaluating the ON/OFF/ON/OFF release switching capability within a narrow pH range.
• Assessing NP release sensitivity in the presence of inflammatory versus healthy cells.

Main Results:

• Mixed AcDex NPs demonstrated rapid cargo release upon decreasing pH from 7.4 to 6.0.
• Achieved rapid and stable ON/OFF/ON/OFF drug release switching within this narrow pH range in 90 minutes.
• Exhibited increased cargo release in the presence of inflammatory cells compared to healthy cells, indicating biological pH sensitivity.

Conclusions:

• Optimized mixed AcDex NPs offer precise and controllable ON/OFF drug release triggered by local pH changes.
• These NPs show potential as a therapeutic platform for managing inflammation by targeting dynamic pH shifts.
• This DDS approach could reduce systemic and local side effects compared to conventional treatments for inflammatory diseases.