Combinatorial peptide synthesis on different solid phases and their thermographic investigation on CO2-binding affinity

Researchers in Germany have developed a thermographic screening approach to identify short peptide sequences that respond to carbon dioxide. Their study, published in Environmental Surfaces and Interfaces, combines combinatorial solid-phase peptide synthesis with infrared thermography and tests whether heat changes can be used as a rapid indicator of peptide-CO₂ interactions.

“Inspired by carboxylase enzymes, which bind CO₂ during biological carbon fixation, we produced a library of 300 different tripeptide sequences on amino-functionalised glass slides,” shares senior and co-corresponding author Magnus S. Schmidt. “The arrays were placed in a sealed thermography system and exposed to a controlled CO₂ atmosphere.”

An infrared camera was used to monitor small temperature differences that can arise when molecular interactions release or absorb heat. Two tripeptides, His(Boc)-Phe-Asn and Phe-Ala-Glu(OtBu), showed reproducible thermographic responses. After contact with CO₂, their temperature differences rose rapidly to approximately 0.10-0.14 K on the glass-slide system, whereas an inactive sequence showed little change. The researchers then synthesised the same candidates on functionalised cellulose membranes and Rink-amide resin.

“The thermal anomalies were again observed, supporting the transferability of the screening concept across different solid phases,” says Schmidt.

The solid support also affected the measured response. “FIB-SEM imaging showed that the cellulose membrane had a more porous structure than the relatively smooth Rink-amide resin,” adds Schmidt. “This suggest that differences in surface area, CO₂ diffusion, and thermal conductivity may contribute to the distinct thermographic profiles.”

“The identified peptide sequences could serve as binding molecules for CO₂ capture,” says lead author Jessica Jung-Fittkau. “Nonetheless, this work represents an early step: the binding properties must be validated on a larger scale, and further studies are needed to optimise peptide performance and integrate the sequences into practical CO₂-capture systems.”

Contact author details:

Magnus S. Schmidt, Faculty Health, Medical and Life Sciences, Institute of Precision Medicine, Organic and Bioorganic Chemistry Lab, Furtwangen University, Campus Villingen-Schwenningen, Jakob-Kienzle-Straße 17, 78054 Villingen-Schwenningen, Germany; Magnus.Schmidt@hs-furtwangen.de

Funder:

The research presented was supported by the Vector Stiftung, Stuttgart, Germany.

Conflict of interest:

All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest or non-financial interest in the subject matter or materials discussed in this manuscript. All authors declare that they have no conflict of interest.

See the article:

Jung-Fittkau, J., Moro, K., Strohm, S., Diebold, J., Kruse, A., & Schmidt, M. S. (2026). Combinatorial peptide synthesis on different solid phases and their thermographic investigation on CO₂-binding affinity. Environmental Surfaces and Interfaces, 4, 356-363. https://doi.org/10.1016/j.esi.2026.06.001