Topology-Dependent Interaction of Cyclic Poly(ethylene glycol) Complexed with Gold Nanoparticles against Bovine Serum Albumin for a Colorimetric Change

Abstract

Unique physical and chemical properties arising from a polymer topology recently draw significant attention. In this study, cyclic poly(ethylene glycol) (c-PEG) was found to significantly interact with bovine serum albumin (BSA), suggested by nuclear magnetic resonance, dynamic light scattering, and fluorescence spectroscopy. On the other hand, linear HO−PEG−OH and MeO−PEG−OMe showed no affinity. Furthermore, a complex of gold nanoparticles and c-PEG (AuNPs/c-PEG) attracted BSA to form aggregates, and the red color of the AuNPs dispersion evidently disappeared, whereas ones with linear PEG or without PEG did not demonstrate such a phenomenon. The interactions among BSA, AuNPs, and PEG were investigated by changing the incubation time and concentration of the components by using UV−Vis and fluorescence spectroscopy.

Polymer Brushes on Nanoparticles for Controlling the Interaction with Protein-Rich Physiological Media

“…The c PEG-Ag NPs exhibited a lower and more uniform particle size . On gold NPs, c PEG brushes formed a thicker layer than the linear counterparts, resulting in enhanced stabilization even when the NPs were frozen, lyophilized, and heated …”

“…108 On gold NPs, cPEG brushes formed a thicker layer than the linear counterparts, resulting in enhanced stabilization even when the NPs were frozen, lyophilized, and heated. 109 Our group demonstrated that cyclic PAOXAs can form ultradense shells that protect NP cores from interacting with proteins. Linear and cyclic PAOXAs with different molar masses (5−6 and 10−11 kDa) and bearing nitrocatechol anchors were used to functionalize SPIONs.…”

PEGylation of silver nanoparticles by physisorption of cyclic poly(ethylene glycol) for enhanced dispersion stability, antimicrobial activity, and cytotoxicity

“… 43 Moreover, AuNPs PEGylated by c -PEG can be used for the colorimetric detection of bovine serum albumin through a unique complexation. 44 The strong physisorption of c -PEG likely arises from the less entropic penalty upon adsorption to the surface compared to the linear counterparts, 45,46 which is also suggested by theoretical and computational studies. 47–51 Bearing this in mind, the physisorption of c -PEG is considered suitable for PEGylation and dispersion stabilization of AgNPs because AgNPs are much less chemically stable than AuNPs, and the thiol chemisorption is essentially inapplicable.…”

Application of Polymer Brush-Shells on Nanoparticles for Controlling Interaction with Serum

“…104 On gold NPs, cPEG brushes formed a thicker layer than the linear counterparts, resulting in enhanced stabilization even when the NPs were frozen, lyophilized, and heated. 105 Our group demonstrated that cyclic PAOXAs can form ultra-dense shells that protect NP cores from interacting with proteins. Linear and cyclic PAOXAs with different molar mass (5-6 kDa and 10-11 kDa) and bearing nitrocatechol anchors were used to functionalize SPIONs.…”