Synthesis and facile end-group quantification of functionalized PEG azides

Area of Science:

• Polymer Chemistry
• Organic Chemistry
• Materials Science

Background:

• Azido-functionalized poly(ethylene glycol) (PEG) are vital for conjugation chemistry and targeted drug delivery.
• Accurate quantification of azide incorporation in PEG polymers is essential for their application.
• Standard 1H Nuclear Magnetic Resonance (NMR) analysis for azide quantification is often hindered by overlapping PEG signals.

Purpose of the Study:

• To develop a straightforward method for quantifying azide incorporation in PEG polymers.
• To overcome the limitations of standard NMR analysis for PEG azide quantification.
• To enable reliable end-group analysis for various bifunctional azido-PEGs.

Main Methods:

• Synthesis of 1,2,3-triazole adducts from PEG azides using a mild "click" reaction.
• Utilizing the synthesized triazole adducts for quantitative 1H NMR analysis.
• Testing the method's compatibility with bifunctional azido-PEGs of varying molecular weights and functional groups.

Main Results:

• A convenient and mild click reaction was established for converting PEG azides to triazole adducts.
• This method provides straightforward, NMR-based quantitative end-group analysis.
• The developed technique is compatible with bifunctional azido-PEGs (2-18 kDa) with diverse functional groups.

Conclusions:

• The click reaction-based triazole adduct formation offers a simplified approach to PEG azide quantification.
• This method enhances the reliability of end-group analysis for functionalized PEG polymers.
• The developed strategy is broadly applicable to various PEG-based systems used in drug delivery and conjugation.