α‑Hydroxyl‑ω‑Thiol‑poly(D,L‑lactide) (PDLLA‑SH, MW 2K) is linear, mono‑thiol‑terminated fully amorphous biodegradable aliphatic polyester. D‑lactide and L‑lactide repeat units are randomly distributed along polymer backbone, disrupting stereoregularity and eliminating crystalline domains. As low‑molecular‑weight thiol‑functional PDLLA derivative, this 2 kDa grade presents low hydrophobicity and fast homogeneous hydrolytic degradation. One polymer terminus bears reactive free thiol (‑SH) group, the opposite terminus retains inert hydroxyl (‑OH). Terminal thiol can participate in thiol‑maleimide click coupling, disulfide bond formation, thiol‑ene Michael addition reactions, enabling covalent conjugation with maleimide‑modified ligands, peptides and biomolecules under mild conditions. It works as monofunctional macromonomer for nanoparticle surface modification, redox‑responsive material construction and short‑term biodegradable biomedical delivery research。
Key Features
- MW: 2000 Da, linear α‑hydroxyl‑ω‑thiol‑terminated poly(D,L‑lactide)
- Fully amorphous non‑crystalline structure, random D/L‑lactide sequence, no melting point
- Low hydrophobicity, fast and uniform hydrolytic degradation versus higher‑MW PDLLA‑SH analogues
- Excellent biocompatibility; degradation produces non‑toxic lactic‑acid metabolites
- Single terminal free thiol (‑SH) group; capable of maleimide coupling, disulfide formation and thiol‑ene reaction; 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 group is oxidation‑sensitive; strictly avoid air exposure, moisture and heavy‑metal contaminants
Applications
- Monofunctional building block for thiol‑click bioconjugation with maleimide‑activated peptides, ligands and biomacromolecules
- Fabrication of redox‑responsive disulfide‑crosslinked PDLLA nanoparticles for short‑term drug‑delivery study
- Thiol‑functional surface engineering of fast‑degrading PDLLA nanocarriers and polymer coatings
- Research‑grade raw material for constructing reactive‑site‑modified biodegradable polyester biomaterials
Handling & Storage
- Store at −20 °C under dry inert nitrogen or argon atmosphere; strictly moisture‑proof and oxygen‑shielded
- Keep hermetically sealed; oxygen and moisture trigger thiol oxidation to form disulfide impurities; 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.