Preparation of Conjugated Polymer Dots as a Fluorescence Turn-On Assay for Bovine Serum Albumin by Interaction with Graphene Oxide

Abstract

Fluorescent conjugated polymers with various monomer compositions were synthesized via Suzuki coupling polymerization and spherically-shaped conjugated polymer dots (CPdot) with uniform size were prepared via conventional reprecipitation technique. Chemically modified graphene oxide (GO) was prepared to use as a component of sensor platform for protein detection. GO showed an excellent interaction with CPdot on its surface via hydrophobic interaction, which, in turn, induced the quenching of the fluorescence of CPdot. Upon exposure to bovine serum albumin (BSA), the quenched fluorescence was recovered, resulting from the release of CPdot from the complex with GO, as BSA adsorbed preferentially on the GO surface.

Co-Assembly of Graphene Oxide and Albumin/Photosensitizer Nanohybrids towards Enhanced Photodynamic Therapy

“…AFM image ( Figure 1 e) and topographic height diagram ( Figure 1 f) of Ce6–BSA–GO nanohybrids show a height of 10–30 nm, also consistent with the size of Ce6-BSA nanoparticles. The loading of Ce6-BSA on the surface of GO should be the result of hydrophobic and π–π stacking interactions between GO and aromatic residues of BSA as revealed by recent studies [ 43 , 44 ]. Meanwhile, it has been demonstrated that such non-covalent interactions between BSA and GO is strong in a physiological condition of 10 mM phosphate buffer solution at pH 7.4 [ 43 ].…”

Merocyanine 540 adsorbed on polyethylenimine-functionalized graphene oxide nanocomposites as a turn-on fluorescent sensor for bovine serum albumin

“…39,40 Upon the addition of GO to the MC540 aqueous solution, the absorption band of MC540 at 502 nm decreases, while the band at 533 nm increases due to the intercalation of the dye molecules into the GO sheets. 41 Thus, the increase in the GO concentration causes an increase in the number of monomeric MC540 molecules. In contrast, upon the addition of the PEI-GO nanocomposites into the aqueous MC540 solution, noticeable variations in the absorption spectrum of the dye are seen, which supports the strong interaction between the MC540 molecules and the PEI-GO nanocomposites (Fig.…”