Multivalent lectin-glycan interactions (MLGIs) are widely employed in biology and play a critical role in modulating many essential biological functions, including recognition, adhesion, and signalling of pathogens and modulation of host cell immune responses. Most pathogens target host cells by forming multivalent interactions with cell surface lectins via their surface specific glycans (or vice versa) to gain entry to host cells to initiate infection. As monovalent interactions between lectins and carbohydrates are characteristically weak, with the dissociation constants (Kds) typically in the mM range, they are too weak to produce a biological response. To compensate this, most lectins form oligomeric structures which cluster multiple carbohydrate recognition domains (CRDs) together to form multivalent binding with glycans to enhance affinity to make bindings biologically functional. The infection processes of many viruses, including HIV, Ebola, West Nile , and more recently, SARS-CoV-2, are mainly initiated or facilitated (in the case of SARS-CoV-2) by binding of viral surface glycans to host cell multimeric lectins (or vice versa). Therefore, elucidating the mechanisms which glycoconjugates form strong and specific MLGIs with multimeric lectins is of great importance and significance, allowing us to design effective glycoconjugates to potently block specific MLGIs, thereby preventing viral infections. Compared to other approaches, this antiviral strategy has a unique advantage because it can effectively prevent viral mutation and acquire resistance. While free glycans can be directly employed for this purpose, they are likely to be ineffective because of their weak monovalent binding with the target lectins. By displaying multiple glycans onto suitable nanoscale scaffolds, the resulting polyvalent glycoconjugates can bind multivalently with multimeric lectins, resulting in greatly enhanced MLGI affinity, up to 5-6 orders of magnitude, over the corresponding monovalent affinity. In this regard, nanomaterials are robust scaffolds for displaying multivalent glycans for potent lectins targeting. In particular, gold nanoparticles, GNPs, are well-suited for constructing polyvalent glycoconjugates, owing to their advantageous properties, such as low-/ nontoxicity, widely available size and shape range, and robust gold-thiol surface chemistry for easy tuning of the glycan density and valency. Notably, their large surface-area-to-volume ratio is also advantageous in forming stable, well presented three-dimensional displays of target glycans. Furthermore, glycan-functionalised GNPs (glycan-GNPs) have excellent colloidal stability, biocompatibility, and high resistance against non-specific interactions, these make them well-suited for a wide range of biological and biomedical applications. Meanwhile, pH is a vitally important environmental stimulus for many biological processes and functions. It also plays a key role in viral infections. Viruses often attach to host cells by binding of their surface specific glycans to host cell lectin receptors (or vice versa) to gain cell entry and infection.