DSPE-PEG36-DBCO

This DSPE-PEG36-DBCO linker is a PEGylated, lipid-compatible scaffold bearing a strained cyclooctyne (DBCO) for copper-free click conjugation in targeted protein degradation workflows. Its amphiphilic design supports stable formulation and efficient bioconjugation, enabling modular assembly of PROTAC constructs with minimal side reactions. The sections below describe its structural features and practical considerations for linker incorporation into PROTAC synthesis.

Structure: The molecule combines a phospholipid (DSPE) hydrophobic anchor with a flexible poly(ethylene glycol) chain that confers solubility and spacing. The DBCO moiety contains a strained cyclooctyne suitable for strain-promoted azide–alkyne cycloaddition, forming a stable triazole linkage.

Reactivity: DBCO reacts selectively with azide-functional partners via strain-promoted azide–alkyne cycloaddition under copper-free conditions. For PROTAC assembly, prepare DBCO- and azide-bearing components in compatible aqueous or mixed solvents, typically buffered to preserve protein-reactive groups. Use mild temperatures and avoid strong nucleophiles or conditions that destabilize azides or sensitive functional handles; purification by standard chromatographic or dialysis methods is commonly applied to remove unreacted species.