Synthesis of Bio-Orthogonal Hydrogels for 3D Cell Culture via Penicillamine β-Thiolactone-Mediated Native Chemical Ligation

Author

• Kaelin E. Marshall, University of New Hampshire, DurhamFollow
• Matthew E. Currier, University of New Hampshire, DurhamFollow
• Nathan J. Oldenhuis, University of New Hampshire, DurhamFollow

Date of Award

Winter 2025

Project Type

Senior Honors Thesis

College or School

COLSA

Department

MCBS

Program or Major

BMCB

Degree Name

Bachelor of Science

First Advisor

Nathan Oldenhuis

Abstract

Many hydrogel systems designed to mimic the extracellular matrix (ECM) employ thiol-based chemistries with undesirable functional groups, including vinyl sulfones and methacrylates. In downstream applications, any unreacted functional groups are problematic and render hydrogels non-viable for human use. Here, we introduce modifications to the Native Chemical Ligation (NCL) mechanism, exploring the elimination of cytotoxic byproducts and increased reaction rate by using a β-thiolactone. The inclusion of the β-thiolactone results in retention of the thiol within the gel, as well as enhanced kinetics due to the thermodynamic favorability of the ring opening and amide formation. We achieved this by functionalizing 4-arm PEG with a cyclized thioester derived from the amino acid penicillamine: penicillamine β thiolactone (PBET). Additionally, our NCL system can incorporate RGD adhesion peptides and small molecules during gelation, an advancement not yet achieved in similar gelation systems.

Recommended Citation

Marshall, Kaelin E.; Currier, Matthew E.; and Oldenhuis, Nathan J., "Synthesis of Bio-Orthogonal Hydrogels for 3D Cell Culture via Penicillamine β-Thiolactone-Mediated Native Chemical Ligation" (2025). Honors Theses and Capstones. 925.
https://scholars.unh.edu/honors/925