Identification of chalcopyrite-binding peptides for flotation applications using phage display and deep sequencing

Phage display is a powerful technology for identifying new ligands, including mineral-selective peptides. However, it is prone to several biases that may lead to false positives or false negatives, particularly due to non-specific binding, amplification bias, and the limited number of clones typically sequenced. By combining phage display with deep sequencing, we detected hundreds of thousands of chalcopyrite-binding peptides across different rounds of selection. Adsorption assays confirmed the strong affinity of the LNSSLRL peptide when produced de novo by chemical synthesis, and demonstrated that unpurified, but desalted, synthetic peptides retain selective binding capacity. These findings support the feasibility of cost-competitive, large-scale production of peptide-based mineral binders.