features, with a greater potential for global effects on the protein backbone, for example, dehydration, protection, and shielding from the external environment. To gain further insights into the contacts between the protein and PEG chains, the minimum distance from the PEG chain to each protein residue was computed. The cutoff distance is set to be 0.35 nm, meaning when the PEG-residue distance is below 0.35 nm, it is considered as direct contact. The contact probability for each residue is then calculated as the number of MD frames when it is in contact with PEG over the total number of frames (Figure ). This analysis shows that atoms in the long PEG chain exhibit more sustained interactions with protein residues than those in the short PEG chain. These differences are evident ) In addition, the long PEG chain not only has a higher probability of staying in contact with the protein but also maintains these interactions for a longer duration compared to the short PEG chain (Figure ). Notably, the contacts between the long PEG chain and protein are especially prolonged for residues 131-141 and 191-202 (Figure ).