Optimization of doxorubicin loading for superabsorbent polymer microspheres: in vitro analysis

Area of Science:

• Materials Science
• Polymer Chemistry
• Drug Delivery Systems

Background:

• Super-absorbent polymers (SAP) are known for their high absorption capacity.
• Doxorubicin is a widely used chemotherapy agent.
• Efficient loading and elution of doxorubicin from delivery vehicles are crucial for effective cancer therapy.

Purpose of the Study:

• To evaluate the capacity of SAP to uptake doxorubicin.
• To demonstrate the phase transfer of doxorubicin onto the SAP matrix.
• To optimize the loading and elution of doxorubicin from SAP for improved handling and efficiency.

Main Methods:

• Phase I involved prehydrating SAP with various solutions (saline, contrast) or using dry SAP, then combining with doxorubicin reconstituted in different solutions. Loading, handling, and elution were assessed using HPLC.
• Phase II tested the top two methods from Phase I, loading doxorubicin (50-100 mg) via single bolus or serial methods, measuring loading and elution over time.

Main Results:

• Dry SAP with normal saline reconstituted doxorubicin showed high loading efficiencies (83.1% and 88.4%).
• SAP exhibited unstable behavior with 100 mg doxorubicin.
• Dry and prehydrated SAP had similar loading/elution profiles, but prehydrated SAP offered superior handling at 50 and 75 mg.

Conclusions:

• SAP can effectively load and phase transfer doxorubicin at 50 and 75 mg.
• Dry loading of SAP provides optimal efficiency and ease of handling for doxorubicin transfer.