New liquid chromatography columns for highlighting the interaction of ligand candidates with humic acid

Abstract

Humic acid was the main compound in soil and reduced the availability of some organic compounds in soils. In this work, humic acid was immobilized for the first time on a homemade neutravidin poly(glycidyl methacrylate‐co‐ethylene dimethacrylate) capillary column with a 20 μm i.d. for the screening of potential ligands to humic acid and the evaluation of their molecular recognition mechanism. This homemade humic acid column enabling it to work at very low backpressure (0.60 MPa at 20 nl/min flow rate), had a long lifetime, excellent repeatability, and negligible non‐specific binding sites. The performance of this affinity humic acid column was demonstrated by the evaluation of recognition assay for a series of known ligands of humic acid (a series of rodenticide molecules) which is the heart of the fragment‐based drug design. In addition, this column was used successfully for highlighting the binding mechanism to humic acid of the severe acute respiratory syndrome coronavirus‐2‐spike protein. As well this new humic acid miniaturized liquid chromatography column developed in this work could be used in the feature for another solute molecule‐humic acid binding studies or for a separative mode.