Immobilization of fluorescent lamp phosphor binding peptides on magnetic carriers for biotechnological particle separation processes

Due to their highly complex chemistry and structure, peptide molecules can have the ability to bind to certain inorganic surfaces with a high affinity and selectivity. This property can be utilized for the functionalization of biohybrid materials, in order to create multifunctional, biocompatible materials. In this context, the functionalization of magnetic carrier particles with selectively surface-binding peptides has a potential to play a key-role in innovative particle separation processes aimed at resource recovery and wastewater treatment.
In the junior research group BioKollekt, we have identified selectively surface-binding peptides with a high affinity to certain Rare Earth Element containing fluorescent lamp phosphors by Phage Surface Display (Lederer et al., 2017, [1]). To complete the potential of these peptides for a separation procedure, we have chemically immobilized these peptides on the surfaces of various magnetic carriers. The magnetic properties of such biocollectors enable an efficient and high-throughput separation process. We investigate the peptide immobilization via different coupling procedures and the resulting biocollectors are characterised with regard to their surface and binding properties. Finally, to optimize the technical application of the biocollectors, we investigate the separation capacity of fluorescent lamp phosphors in a rotary permanent magnet separator that was specifically designed for biotechnological purposes (Boelens et al., 2021, [2]).
In this work, the holistic view of a peptide-assisted biomagnetic particle separation process and its upscalibility for resource recovery processes is discussed.

Reference list
1. Lederer et al.; Identification of lanthanum-specific peptides for future recycling of rare earth elements from compact fluorescent lamps: Peptides for Rare Earth Recycling. Biotechnol. Bioeng. 2016, 114, doi:10.1002/bit.26240.
2. Boelens et al.; High-Gradient Magnetic Separation of Compact Fluorescent Lamp Phosphors: Elucidation of the Removal Dynamics in a Rotary Permanent Magnet Separator. Minerals 2021, 11, doi:10.3390/min11101116.