Used primarily as a hydrophilic linker in the synthesis of pharmaceuticals and bioconjugates. Its polyether chain enhances solubility in aqueous environments, making it valuable in prodrug design and targeted drug delivery systems. Commonly employed in the development of antibody-drug conjugates (ADCs) to improve pharmacokinetic properties. Also utilized in surface modification of nanoparticles to reduce protein adsorption and increase circulation time in vivo.