Long-term release of a thiobenzamide from a backbone functionalized poly(lactic acid)

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Medical Chemistry

Background:

• Hydrogen sulfide (H2S) is a crucial molecule in medicine.
• Existing methods for sustained H2S delivery are limited.
• Thiobenzamide is a known precursor for H2S generation.

Purpose of the Study:

• To develop a novel polymer for long-term H2S release.
• To synthesize and characterize copolymers of L-lactide and functionalized lactide.
• To create and evaluate microparticles for controlled thiobenzamide delivery.

Main Methods:

• Copolymerization of L-lactide with a 4-hydroxythiobenzamide-functionalized lactide.
• Synthesis of functionalized lactide via thiol addition to an α,β-unsaturated lactide using I2 catalysis.
• Fabrication of microparticles from synthesized copolymers.
• In vitro degradation studies of microparticles in buffered water.

Main Results:

• Successfully synthesized copolymers with molecular weights of 8–88 kg mol−1 and low polydispersity (PDI < 1.50).
• Fabricated microparticles with average diameters of 0.53 μm and 12 μm.
• Demonstrated slow release of thiobenzamide from smaller microparticles over 4 weeks.

Conclusions:

• Developed a new polymer-based system for the long-term delivery of H2S precursors.
• The synthesized microparticles offer tunable release profiles for thiobenzamide.
• This approach provides a promising platform for sustained H2S therapy.