α‑Hydroxyl‑ω‑Thiol‑poly(L‑lactide) (PLLA‑SH, MW 5K) is linear, mono‑thiol‑terminated semi‑crystalline biodegradable aliphatic polyester. The polymer backbone is composed of stereoregular L‑lactide repeating units and presents inherent semi‑crystallinity, which is distinctly different from fully‑amorphous PDLLA. Compared with MW 2K PLLA‑SH, this 5 kDa grade possesses moderate hydrophobicity and intermediate homogeneous hydrolytic degradation rate. One polymer terminus carries reactive thiol (‑SH) group, the opposite terminus retains inert hydroxyl (‑OH). Terminal thiol participates in thiol‑ene click reaction, disulfide bond formation, and covalently couples with maleimide, pyridyl disulfide and gold‑containing substrates under mild conditions for modification of targeting ligands and biomolecules. It serves as monofunctional thiol‑functional building block for medium‑degradation‑rate nanoparticle/micelle fabrication, surface sulfhydryl modification and redox‑responsive biomedical delivery research.
Key Features
- MW: 5000 Da, linear α‑hydroxyl‑ω‑thiol‑terminated poly(L‑lactide)
- Semi‑crystalline stereoregular L‑lactide structure, distinct from amorphous PDLLA
- Moderate hydrophobicity, intermediate and uniform hydrolytic degradation versus 2K PLLA‑SH
- Excellent biocompatibility; degrades into non‑toxic L‑lactic acid in vitro and in vivo
- Single terminal thiol (‑SH) reactive group for thiol‑ene, thiol‑maleimide coupling and disulfide cross‑linking; opposite polymer end is inert hydroxyl ‑OH
- Narrow molecular‑weight distribution, stable batch‑to‑batch reproducibility; high thiol end‑group functionality
- Soluble in DCM, CHCl₃, THF, DMF, acetone; insoluble in water
- Thiol‑terminated polymer; sensitive to oxygen and heavy‑metal ions; avoid prolonged air exposure; inert‑gas sealed storage is required
Applications
- Monofunctional thiol‑containing building block for maleimide‑modified ligand conjugation and thiol‑ene click chemistry
- Preparation of thiol‑functional PLLA nanoparticles and micelles with medium degradation speed for drug‑delivery research
- Sulfhydryl surface modification of polyester materials for gold nanoparticle immobilization and disulfide‑based cross‑linking
- Precursor for synthesizing disulfide‑linked redox‑responsive degradable polymer conjugates
- Research‑grade raw material for redox‑sensitive biodegradable biomedical polymer study
Handling & Storage
- Store at −20 °C under dry inert nitrogen or argon atmosphere; strictly moisture‑proof, minimize oxygen exposure
- Keep hermetically sealed; oxygen may oxidize thiol groups into disulfide bonds and humidity accelerates polyester backbone hydrolysis; avoid repeated freeze‑thaw cycles
- For research‑only use; not intended for clinical or diagnostic applications
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.