m-PEG3-aldehyde is a PEG-based linker for PROTACs which joins two essential ligands, crucial for forming PROTAC molecules. This linker enables selective protein degradation by leveraging the ubiquitin-proteasome system within cells.

PROTAC molecules comprise two distinct ligands connected by a linker: one ligand targets an E3 ubiquitin ligase, while the other binds to the intended protein. This design allows PROTACs to manipulate the cell's ubiquitin-proteasome system for the selective degradation of specific proteins. Additionally, the efficacy of anti-mPEGs is primarily influenced by the polymer backbone lengths and the hydrophobicity of their end-groups rather than their structural similarity to the methoxy terminus of the immunogenic polymer. Moreover, aldehydes are known to react with hydrazide and aminooxy groups, which are frequently utilized in biomolecular probes for the labeling and crosslinking of carbonyls (oxidized carbohydrates), enhancing their utility. The incorporation of a hydrophilic PEG spacer enhances solubility in aqueous environments.