DSPE-PEG(2000) Carboxylic Acid A80135 (Legacy code 880135) 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[carboxy(polyethylene glycol)-2000] (sodium salt)

DSPE-PEG (2000) Carboxylic Acid (DSPE-PEG-COOH) is a functionalized PEGylated phospholipid developed for surface modification of liposomes and lipid nanoparticles. The lipid combines a hydrophobic DSPE anchor with a PEG 2000 spacer, terminating in a reactive carboxylic acid group that can be used for downstream conjugation strategies.

While standard methoxy-terminated PEG lipids primarily provide steric stabilization, DSPE-PEG-COOH is able to add a chemically accessible attachment point without sacrificing the circulation-enhancing properties associated with PEGylated systems. This design allows formulators to introduce targeting functionality directly onto nanoparticle surfaces.

The terminal carboxyl group readily participates in established coupling workflows. Following activation with EDC/NHS, EDC/sulfo-NHS, HATU, or related chemistries, the lipid can form stable amide bonds with a wide range of amine-containing biomolecules, making it a versatile component for advanced nanoparticle engineering. Avanti Research™ supplies this material in 10, 25, 50, 100, and 500 mg powdered quantities.

Application

DSPE-PEG-COOH is commonly incorporated into liposomes and lipid nanoparticles when surface-bound targeting ligands are required. By introducing the lipid at relatively low molar percentages, researchers can create PEGylated carriers that retain reactive sites for post-formulation conjugation. This approach is widely used in receptor-targeted delivery systems designed to improve cellular uptake and tissue specificity.

The lipid has been utilized in nanoparticle platforms functionalized with antibodies, peptides, aptamers, and other targeting molecules. Published studies report its use in antibody-directed liposomal systems for nucleic acid delivery, including formulations targeting ICAM-1 and EGFR. Its compatibility with established bioconjugation chemistries makes it a flexible tool for developing next-generation drug, gene, and RNA delivery vehicles.

For non-reactive stealth PEGylation without a coupling handle, see 18:0 PEG2000 PE (DSPE-PEG2000, methoxy).

Key features

• Reactive carboxylic acid terminus for covalent attachment of amine-bearing biomolecules
• Supports EDC/NHS, sulfo-NHS, and HATU-mediated conjugation workflows
• Combines surface functionalization with PEG-mediated steric stabilization
• Compatible with antibodies, Fab fragments, peptides, aptamers, and small-molecule targeting ligands
• Greater than 98% purity for reproducible formulation and bioconjugation studies

Avanti Research™ is a globally trusted supplier of specialty lipids, supporting researchers and pharmaceutical developers from early discovery through clinical-scale formulation programs.

Explore similar products

• 18:0 PEG2000 PE (DSPE-PEG2000, methoxy) — non-reactive stealth analog
• Azido-PEG2000-Carboxy — for click chemistry workflows
• DOPE-PEG(2000) Carboxylic Acid — unsaturated bioconjugation lipid

  References

Guo, Peng, et al. “Dual Complementary Liposomes Inhibit Triple-Negative Breast Tumor Progression and Metastasis.” Science Advances, vol. 5, no. 3, 20 Mar. 2019, p. eaav5010, https://doi.org/10.1126/sciadv.aav5010

Guo, P., Yang, J., Jia, D., Moses, M. A., & Auguste, D. T. (2016). ICAM-1-Targeted, Lcn2 siRNA-Encapsulating Liposomes are Potent Anti-angiogenic Agents for Triple Negative Breast Cancer. Theranostics, 6(1), 1–13. https://doi.org/10.7150/thno.12167

 Menon, Ipshita, et al. “Fabrication of Active Targeting Lipid Nanoparticles: Challenges and Perspectives.” Materials Today Advances, vol. 16, Dec. 2022, p. 100299, https://doi.org/10.1016/j.mtadv.2022.100299