HO-Ste-Glu(AEEA-AEEA-OSu)-OH

HO-Ste-Glu(AEEA-AEEA-OSu)-OH is a synthetic heterobifunctional crosslinker based on a glutamic acid (Glu) scaffold. It contains a lipophilic stearic acid (Ste) moiety at the α-carboxyl position, linked via an ester or amide bond, and an N-hydroxysuccinimide (OSu) ester attached to the γ-carboxyl through two hydrophilic and flexible AEEA (2-[2-(2-aminoethoxy)ethoxy]acetic acid) units. The stearic acid offers membrane anchoring or hydrophobic interactions, while the OSu ester reacts specifically with primary amines to form stable amide bonds, facilitating conjugation to amine-containing molecules. The glutamic acid backbone allows further modification, supporting the development of membrane-targeting drug delivery systems, protein surface modifications, and novel amphiphilic biomaterials.

Appearance

• White to off-white solid or viscous liquid

• Amphiphilic, potentially forming micelles in aqueous solutions

Source

• Chemically synthesized by specialized bioconjugation reagent manufacturers or custom synthesis labs

• Usually not a generally stocked chemical product

Molecular Weight

• Approximately 757.9 g/mol (theoretical value; variation possible due to counterions or residual solvents)

Structure

• Glutamic acid core with stearic acid at α-carboxyl

• γ-carboxyl modified with amide-linked AEEA-AEEA spacer ending in OSu ester

Biological Activity

• Inherent activity unlikely; depends on conjugated molecules

• Stearic acid promotes membrane affinity

• AEEA linkers provide biocompatibility, reduce nonspecific binding

• Glutamic acid scaffold may affect biological recognition or metabolism

Purity and Microbial Contamination

Shelf Life and Storage

• Store at −20°C in dry, inert atmosphere (argon or nitrogen)

• Protect from light and moisture

• OSu ester is hydrolytically sensitive; avoid water exposure

• Shelf life typically 6–12 months

Application

• Membrane-targeting drug delivery by conjugating drugs to lipophilic anchors

• Lipopeptide synthesis with enhanced membrane affinity

• Protein surface modification for membrane interaction, targeting amine groups

• Nanoparticle functionalization with amphiphilic features for targeting and biocompatibility

• Biomaterial design incorporating hydrophobic and hydrophilic elements

Key Characteristics

• Heterobifunctional: stearic acid (lipophilic) and OSu ester (amine-reactive)

• Amphiphilic molecule combining hydrophobic and hydrophilic elements

• Biocompatible AEEA linker units reduce steric hindrance and nonspecific interactions

• OSu ester reacts specifically with primary amines to form stable amide bonds

• Glutamic acid scaffold enables branching and conjugation versatility

• Extended hydrophilic spacer improves molecular flexibility and conjugation efficiency

Citation 

• Lipopeptide Synthesis: search “Synthesis and biological activity of lipopeptides”

• Stearic Acid Conjugation: “Stearic acid-modified nanoparticles for targeted drug delivery”

• OSu Ester Chemistry: “NHS ester-mediated protein conjugation”

• AEEA Linkers: “AEEA linkers improve peptide solubility and reduce aggregation” (Bioconjugate Chemistry)

• Membrane-Anchoring Peptides: “Design and synthesis of membrane-anchoring peptides”

• Glutamic Acid Scaffolds: “Glutamic acid-based dendrimers for drug delivery”

• Amphiphilic Molecules: “Amphiphilic polymers for drug encapsulation and delivery”

• NHS Ester Protein Modification: “One-step protein modification using activated esters” (Bioconjugate Chemistry)

• PEG-based NHS Crosslinkers: “Homobifunctional and heterobifunctional PEG crosslinkers” (Biomaterials)

• Lipid-Modified Bioconjugates: “Lipid modification enhances cellular uptake of bioconjugates” (Journal of Controlled Release)