Identification of Peptide Binding Motifs for Calcium Sulfate Hemihydrate using Phage Display

Selective control over crystallization in complex multicomponent systems such as hydrating cements is a key issue in modern material science. In this context, rational selection‐based approaches appear highly promising in the quest for new additive chemistries. Here we have used phage display to identify peptide structures showing high affinity to adsorb on the surfaces of calcium sulfate hemihydrate (also referred to as bassanite), an important hydraulic binder employed in large scales by the construction industry. The results suggest a triplet of amino acids consisting of aspartic acid, serine and leucine, to maintain strong interactions with the surfaces of hemihydrate particles. This notion is confirmed by actual hydration experiments, in which the identified peptide motif provides strictly selective effects during the transformation of bassanite into more stable gypsum. Our work thus contributes to a better understanding of hydraulic binders and their required improvement for a sustainable future. The hydration of bassanite (calcium sulfate hemihydrate) into gypsum (the dihydrate) is a fundamental reaction underlying the working principle of conventional plasters. To achieve selective control over this process, peptide structures showing strong interactions with the mineral surfaces were rationally identified by means of phage display. The results highlight the potential of this biophysical technique in the design of new crystallization additives for sustainable construction solutions.