Evaluation of Antiviral Activity of Lactoferrin in Bovine Milk Toward Fondaparinux Using Ordered Porous Layer Interferometry

Lactoferrin (LF) is a bioactive molecule that plays a pivotal role in innate immunity and is widely present in dairy products. It has been demonstrated to restrict viral infections by blocking binding sites on heparan sulfate (HS). However, existing analytical methods primarily focus on the LF content rather than its bioactivity, highlighting the need for a dedicated approach to antiviral LF analysis. Developing an appropriate tool for antiviral LF analysis in dairy products is crucial for consumer welfare and product quality control, as the daily intake of LF-rich products offers significant health benefits. However, in one of the primary LF-rich dietary sources, bovine milk, the main limitation of current analysis methods is the lack of an efficient receptor for characterizing antiviral LF. In this study, we developed fondaparinux as a promising receptor for antiviral LF analysis and introduced ordered porous layer interferometry (OPLI) for real-time, in situ monitoring of antiviral LF. Furthermore, we compared the proposed method with the enzyme-linked immunosorbent assay (ELISA) and evaluated antiviral LF content across different milk samples.