The hidden potential of small synthetic molecules and peptides as affinity ligands for bioseparations

While extensively used as drugs, small synthetic molecules have not yet been widely applied in the industry as affinity ligands for the purification of biopharmaceuticals. Yet, a substantial amount of published research indicates that synthetic ligands, such as triazine scaffolds, amino acids, and peptides show a great deal of promise for becoming the next generation affinity ligands for bioseparations. In this review, we present a comprehensive account on small synthetic ligands, from triazine dyes to the most recent polycyclic peptide ligands, selected for targeting high-value biopharmaceuticals, such as immunoglobulins, blood factors and therapeutic enzymes. These ligands could play a significant role in improving downstream processing and helping the bioprocessing industry overcome the urgent issues of costs and availability posed by growing economies on the global pharmaceutical market.