Nylon Affinity Networks Capture and Sequester Two Model Bacteria Spiked in Human Plasma

Ensuring bacterial safety of blood transfusions remains a critical focus in medicine. We investigated a novel pathogen reduction technology utilizing nylon functionalized with synthetic dyes (nylon affinity networks) to capture and remove bacteria from plasma. In the initial screening process, we spiked phosphate buffer solution (PBS) and human plasma (1 mL each) with 10 or 100 colony forming units (cfu) of either Escherichia coli or Staphylococcus epidermidis, exposed the suspensions to affinity networks and assessed the extent of bacterial reduction using agar plate cultures as the assay output. Nineteen synthetic dyes were tested. Among these, Alcian Blue exhibited the best performance with both bacterial strains in both PBS and plasma. Next, bacterial suspensions of approximately 1 and 2 cfu/mL in 10 and 50 mL, respectively, were treated with Alcian Blue affinity networks in three sequential capture steps. This procedure resulted in complete bacterial depletion, as demonstrated by the lack of bacterial growth in the remaining fraction. The viability of the captured bacteria was confirmed by plating the post-treatment affinity networks on agar. Alcian Blue affinity networks captured and sequestered a few plasma proteins identified by liquid chromatography tandem mass spectrometry. These findings support the potential applicability of nylon affinity networks to enhance transfusion safety, although additional investigations are needed.