We have found previously that GNP-glycans prepared using the LA-glycan ligands and their reduced DHLA-forms have identical Dh value and stability. Therefore, the air-stable LA-glycan ligands were directly used to make the GNP-glycans without reduction. Since the LA-EG4-DiMan and LA-EG4-OH spacer ligands have the same GNP anchoring and EG4-linker groups, they should have the same GNP binding properties. Therefore, the GNP surface ligand contents should be the same as those used in GNP conjugation and can be readily tuned by varying the solution glycan and spacer ligands ratio. The resulting G5-glycan conjugates were purified by ultra-filtration using 30K MWCO filter tubes and washing with pure water as described previously. The G13-and G27-glycan conjugates were purified by centrifugation and washing with pure water. The unbound free ligands in the supernatant and washing were collected and used to determine the Gx surface glycan valency. The Gx-glycan conjugates were found to completely resist NaCl (250 mM) induced aggregation, suggesting their surfaces were successfully functionalized with the desired ligands (the citrate stabilized GNPs readily aggregate in moderate NaCl content, due to effective screening their electrostatic repulsion). The Gxglycans were uniform and monodisperse in both water and a binding buffer (20 mM HEPES, 100 mM NaCl, 10 mM CaCl2, pH 7.8) with Dhs of ∼13, ∼22, and ∼32 nm for G5-, G13-and G27-DiMan, respectively (SI, Figs. ). These Dhs were a few nm larger than their corresponding citrate stabilized Gxs, as expected. The Gx-glycan solutions were highly stable; no changes of physical appearance or precipitation were observed after prolonged storage (>12 months) in a fridge at 4 o C.