Thiol‑Poly(ε‑caprolactone) (PCL‑SH, MW 5K) is a monothiol‑terminated hydrophobic biodegradable poly(ε‑caprolactone). Compared with lower‑molecular‑weight PCL‑SH (2K, 3K), the 5 kDa polymer exhibits significantly increased hydrophobicity and crystallinity, along with slower hydrolysis degradation rate. The terminal reactive thiol (-SH) enables thiol‑maleimide click chemistry, disulfide exchange reaction, and covalent immobilization onto gold‑based surfaces. This polymer is widely used for constructing hydrophobic cores of polymeric micelles, nanoparticles, and developing redox‑responsive biomaterials for drug delivery and tissue‑engineering research.
Key Features
- MW: 5000 Da, single‑end thiol functionalized poly(ε‑caprolactone)
- Markedly higher hydrophobicity and crystallinity vs 2 K / 3 K PCL‑SH
- Biocompatible, slower hydrolytic degradation under physiological conditions
- Reactive thiol group for maleimide conjugation and gold‑surface anchoring
- Narrow molecular weight distribution, excellent batch‑to‑batch repeatability
- Soluble in DCM, CHCl₃, THF; insoluble in water
Applications
- Fabrication of highly hydrophobic PCL‑based micelles and nanoparticles for hydrophobic drug encapsulation
- Bioconjugation with maleimide‑modified peptides, proteins and targeting ligands
- Surface modification of gold nanoparticles and gold‑coated biomaterial substrates
- Preparation of redox‑responsive disulfide‑linked polymer‑drug conjugates
- Construction and surface modification of biodegradable tissue‑engineering scaffolds
Handling & Storage
- Store at −20 °C under inert nitrogen or argon atmosphere
- Keep dry, avoid moisture ingress and repeated freeze‑thaw cycles
- Thiol groups are susceptible to oxidation; minimize exposure to air
- For research‑only use; not for clinical or diagnostic applications
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.