Physics / mechanism
Biodegradable aliphatic polyesters synthesised via ring-opening polymerisation of cyclic monomers. PLA (polylactic acid) degrades hydrolytically in weeks–months; PLGA (poly lactic-co-glycolic acid) tuneable by lactide:glycolide ratio (50:50 degrades ~1–2 months; 85:15 ~5–6 months); PCL (polycaprolactone) slowest, 2–4 years. Key parameters: Mw (10–200 kDa), glass transition temperature (PCL Tg ≈ −60 °C, PLA ≈ 55–60 °C), crystallinity, and surface erosion vs. bulk erosion mode. FDA-cleared for drug delivery, sutures, tissue scaffolds. State of the art: electrospun PLGA scaffolds at sub-micron fibre diameters, controlled-release depots with ±10% encapsulation efficiency, and 3D-printed PCL bone scaffolds with compressive moduli approaching 50–100 MPa.
Competitive landscape
Competing material classes include natural polymers (collagen, chitosan, hyaluronic acid — better cell signalling, worse batch consistency), polyhydroxyalkanoates (PHAs — fully bio-derived but costlier), and non-degradable PEEK or titanium implants where permanent structural load-bearing is required. For drug delivery, lipid nanoparticles (LNPs) increasingly compete on encapsulation efficiency and scalability. Hydrogels (PEG-based) dominate soft-tissue applications where mechanical compliance matters more than degradation rate.
Companies using
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Frontier (open questions)
- To be added.