PEG Linkers | Bioconjugation PEG Reagents for ADC and Drug Delivery – Page 27

Polyethylene glycol (PEG) linkers and PEGylation reagents are widely used tools in bioconjugation and drug development to improve the performance of biomolecules and small-molecule therapeutics. PEG linkers consist of flexible, hydrophilic chains of polyethylene glycol that can be functionalized with reactive groups (e.g., NHS esters, maleimides, azides) to enable efficient coupling to proteins, peptides, antibodies, or other payloads. Through PEGylation these reagents help enhance aqueous solubility, reduce aggregation, and minimize non-specific interactions, while also increasing molecular stability and extending systemic circulation half-life by reducing renal clearance and proteolytic degradation. As a result, PEG linkers play a critical role in applications such as antibody–drug conjugates (ADCs), targeted protein degraders (TPDs), nanoparticle and lipid delivery systems, and diagnostic probes, where controlled spacing, flexibility, and biocompatibility are essential for optimal biological performance.