Where ∆𝑚𝑚 is the total mass uptake of AuNPs in ng/cm 2 , 𝑚𝑚 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 = 1.5 • 10 -8 𝑛𝑛𝑛𝑛 is the estimated mass of a single AuNP with a diameter of 11.4 +/-0.75 nm. Fig. shows clear increase in the density of captured AuNP with increase in size of the tether, for the same number of receptors. As seen from Fig. , the 0.7 nm long tether can possibly trap up to 0.2 NPs per 1000 molecules of amine receptors while this density can reach up to 2.3 NPs per 1000 molecules of receptor (for 7.8 nm long tether) before increasing by an order of magnitude due to the presence of multilayers and thus reaching 52 NPs per 1000 molecules of receptor in the case of APT-10k. Despite the similar the tether densities for tether lengths of 3.2, 4.5 and 7.8 nm (Fig. ), the AuNP/receptor ratios show a clear increase with increase in tether lengths (Fig. ).