Surface Acoustic Wave Biosensors for the Quantification of TNF-α/SPD-304 Interaction

In this study, a surface acoustic wave (SAW) biosensor has been investigated to quantify the affinity and to estimate the binding kinetic between tumor necrosis factor α (TNF-α) and its inhibitor: SPD-304. To the best of our knowledge this is first ever report on real time and label free monitoring of TNF-α/ SPD-304 affinity. Effects of the SPD-304 solvent and DMSO cosolvent on TNFα/SPD-304 interaction have been investigated. Gravimetric results indicate that the limit of detection (LOD) of the developed biosensor was of order of 10 nM and that DMSO cosolvent influences the kinetic of interaction, the saturation value, and thus the value of the dissociation constant (Kd) of the TNF-α / SPD-304 system.