JenKem Technology provides high-purity PEG linkers with various active groups and a range of E3 ligand-linker conjugates to assist with your PROTAC-related projects. Newsletter PROTAC PEG Linkers

PROTAC (Proteolysis Targeting Chimera) is a novel technology that induces the targeted protein degradation by the ubiquitin–proteasome system. A PROTAC molecule consists of a ligand binding to the target protein, a ligand for recruiting an E3 ligase, and a linker.

The linker plays an important role in a PROTAC. The most common motifs incorporated into PROTAC linker structures are PEGs of different lengths. Employing a PEG spacer in the linker influences the properties of the PROTAC:

  • The PEG linker increases the PROTAC’s water solubility, affecting the cell permeability, thereby improving oral absorption
  • Linker length contributes to degradation efficiency and PEG molecules can be constructed with various lengths
  • Bifunctional PEG linkers enable the rapid and facile assembly of structures containing different attachment sites


Amino PEG2 Propionic Acid, HCl Salt, MW 213.7
Amino PEG3 Propionic Acid, HCl Salt, MW 257.7
Amino PEG4 Propionic Acid, HCl Salt, MW 301.8
Amino PEG2 Acetic Acid, HCl Salt, MW 199.6
Amino PEG3 Acetic Acid, HCl Salt, MW 243.7
Amino PEG4 Acetic Acid, HCl Salt, MW 287.7
Hydroxyl PEG4 Amine, HCl Salt, MW 229.7
Hydroxyl PEG3 Azide, MW 175.2
Azido PEG3 Acetic Acid, MW 233.2
Azido PEG4 Propionic Acid, MW 291.3
Alkyne PEG5 Propionic Acid, MW 348.4
Alkyne PEG6 Amine, HCl Salt, MW 311.8
Propionic Acid PEG5 Propionic Acid, MW 382.4


(S,R,S)-AHPC hydrochloride


(S,R,S)-AHPC PEG2 Propionic Acid, MW 618.7
(S,R,S)-AHPC PEG4 Propionic Acid, MW 706.9
(S,R,S)-AHPC PEG6 Propionic Acid, MW 795.0
(S,R,S)-AHPC PEG2 Amine, HCl Salt, MW 612.2
(S,R,S)-AHPC PEG4 Amine, HCl Salt, MW 700.3
(S,R,S)-AHPC PEG4 Azide, MW 703.9
(S,R,S)-AHPC PEG5 Alkyne, MW 760.9
Thalidomide-O PEG4 Propionic Acid, MW 522.5
Thalidomide-O PEG4 Succinimidyl Propionate, MW 619.6
Thalidomide-O PEG4 tert-Butyl Propionate, MW 578.6
Thalidomide-O PEG5 Amine, HCl Salt, MW 530.0
Thalidomide-O PEG5 Azide, MW 519.5
Thalidomide-O Amido PEG5 Azide, MW 576.6
Thalidomide-O PEG4 Alkyne, MW 488.5
Thalidomide-O Amido PEG4 Alkyne, MW 545.5
Pomalidomide PEG3 Propionic Acid, MW 477.5
Pomalidomide PEG4 Phenyl Amine, Free Amine, MW 540.6
Pomalidomide PEG5 Azide, MW 518.5

Please contact us at for more information about our linkers for PROTAC applications.


  1. Zhou X, et al., PROTAC: A promising technology for cancer treatment. Eur J Med Chem. 2020; 203:112539.
  2. Troup RI, et al., Current strategies for the design of PROTAC linkers: a critical review. Explor Target Antitumor Ther. 2020; 1:273-312.

Founded in 2001 by experts in PEG synthesis and PEGylation, JenKem Technology specializes exclusively in the development and manufacturing of high quality polyethylene glycol (PEG) products and derivatives, and related custom synthesis and PEGylation services. JenKem Technology is ISO 9001 and ISO 13485 certified, and adheres to ICH Q7 guidelines for GMP manufacture. The production of JenKem® PEGs is back-integrated to in-house polymerization from ethylene oxide, enabling facile traceability for regulated customers. JenKem Technology caters to the PEGylation needs of the pharmaceutical, biotechnology, medical device and diagnostics, and emerging chemical specialty markets, from laboratory scale through large commercial scale.