Heparin-conjugated star-shaped PLA for improved biocompatibility

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Biodegradable polymers like poly(lactic acid) (PLA) are widely used in medical devices.
• Enhancing the hemocompatibility and bioactivity of PLA is crucial for implantable applications.
• Heparin is a well-known anticoagulant and cell-interactive molecule.

Purpose of the Study:

• To synthesize and characterize star-shaped poly(lactic acid)-heparin (sPLA-Hep) conjugates.
• To evaluate the surface properties, hemocompatibility, and cell interactions of sPLA-Hep.
• To explore the potential of sPLA-Hep as a blood/tissue-compatible biomaterial.

Main Methods:

• Star-shaped PLA (sPLA) was functionalized with heparin using carbonyldiimidazole (CDI) chemistry.
• Surface heparin content was quantified.
• Surface hydrophilicity was assessed.
• Activated partial thromboplastin time (APTT) assay was used to measure clotting time.
• Protein adsorption and platelet adhesion were evaluated.
• Fibroblast cell culture was performed to assess cell spreading.

Main Results:

• sPLA-Hep exhibited a surface heparin content of 1.43 microg/cm(2).
• The sPLA-Hep surface showed increased hydrophilicity compared to control surfaces.
• sPLA-Hep significantly prolonged clotting time (APTT) compared to sPLA and linear PLA-Hep.
• Reduced protein adsorption and platelet adhesion were observed on the sPLA-Hep surface.
• Enhanced fibroblast cell spreading was noted on the sPLA-Hep surface.

Conclusions:

• The incorporation of heparin into sPLA effectively reduces surface-induced thrombosis.
• sPLA-Hep demonstrates improved hemocompatibility and favorable cell interaction properties.
• sPLA-Hep holds promise as a biodegradable material for blood/tissue-compatible implantable medical devices and tissue engineering scaffolds.