However, by using the 𝐾 𝑑 and 𝑘 𝑜𝑛 rate coefficients measured by our QD-FRET thermodynamic (at 20 o C) and kinetic assays, respectively, a more plausible 𝑘 𝑜𝑓𝑓 of ~0.05 s -1 (𝑘 𝑜𝑓𝑓 = 𝑘 𝑜𝑛 𝐾 𝑑 ) is obtained for both DC-SIGN and DC-SIGN-C. As the 𝐾 𝑑 value was measured under equilibrium conditions, this calculated 𝑘 𝑜𝑓𝑓 should be an accurate reflection of the natural dissociation rate. In fact, this calculated 𝑘 𝑜𝑓𝑓 value broadly agrees with that measured by SPR (e.g. ~0.1 s -1 ) between surface immobilized DC-SIGN and DiMan coated gold nanoparticles (GNPs, ~1.2 nm in diameter), which does not rely on a competitor. Despite some differences in binding environment (surface immobilized vs. solution) and core nanoparticle sizes (~4 vs. ~1.2 nm for QD vs. GNP), the good agreement between the calculated 𝑘 𝑜𝑓𝑓 from our QD-FRET assays and that measured by SPR for the same pair of lectin and glycannanoparticles demonstrates that our QD-FRET assays are highly credible for probing a variety of important binding thermodynamic and kinetic parameters for MLGIs.