Low‑molecular‑weight PCL backbone fitted with terminal maleimide reactive moiety addresses experimental needs for fast thiol‑directed bioconjugation paired with short‑term hydrolytic breakdown. Unlike higher‑molecular‑weight PCL variants, this 2 K polymer delivers low crystallinity and excellent solvation performance across common anhydrous organic solvents. Its maleimide terminus executes highly selective Michael‑addition coupling toward thiol‑bearing peptides, proteins and small‑molecule ligands within mild pH windows, generating chemically stable thioether linkages. Researchers leverage this reactive hydrophobic polymer to construct rapidly degrading nanoparticle platforms, carry out surface functionalization workflows, and build modular polymer‑biomolecule conjugates designed for short‑term in vitro and transient in‑vivo assessment.
Key Features:
- Low‑crystallinity 2 kDa poly(ε‑caprolactone) chain terminally tethered to maleimide group; optimized for rapid thiol‑click coupling under pH‑controlled conditions
- Minimal chain entanglement grants superior dissolution profile in DCM, THF and chloroform, supporting convenient nanoprecipitation and solution‑phase bioconjugation setups
- Fast hydrolytic degradation profile; polymer matrix erodes over short experimental windows without leaving persistent polymeric residues
- Suppressed non‑specific amine cross‑reactivity when reactions are maintained between pH 6.5‑7.5, lowering background signal for biolabeling workflows
- Tight end‑group fidelity verified by NMR characterization; low residual catalyst burden suitable for proof‑of‑concept biological lab assays
Applications:
- Rapid‑eroding thiol‑functionalized polymeric micelles and nanoparticles for short‑term drug‑loading and in‑vitro cellular studies
- Covalent surface decoration of pre‑fabricated substrates with cysteine‑containing peptides for transient cell‑interaction assays
- Generation of transient polymer‑protein bioconjugates intended for acute biological evaluation rather than long‑term implantation
- Prototype screening of targeting‑ligand modified PCL constructs before scaling up to higher‑molecular‑weight material grades
- Bench‑scale exploratory thiol‑maleimide conjugation method development using hydrophobic polyester building blocks
Handling & Storage: Preserve solid material at −20 °C under dry inert‑gas atmosphere, shielded from light; maleimide moiety is susceptible to hydrolytic deactivation upon moisture exposure. Let the sealed vial reach full room‑temperature equilibrium inside a desiccator prior to opening, to stop atmospheric water condensation contaminating the powder. Prepare working solutions exclusively with anhydrous, thiol‑free organic solvents immediately before running experiments; discard unused dissolved aliquots instead of banking them. Intended solely for laboratory research applications; not validated for human clinical usage.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.