Attaching DNA to Gold Nanoparticles With a Protein Corona

Abstract

DNA-functionalized gold nanoparticles (AuNPs) have been widely used in directed assembly of materials, biosensors, and drug delivery. This conjugate may encounter proteins in these applications and proteins may affect not only DNA adsorption but also the function of the attached DNA. Bovine serum albumin (BSA) with many cysteine residues can strongly adsorb on AuNPs and this conjugate showed high colloidal stability against salt, acid and base. Similar protection effects were also observed with a few other common proteins including catalase, hemoglobin, glucose oxidase, and horseradish peroxidase. DNA oligonucleotides without a thiol label can hardly displace adsorbed BSA, and BSA cannot displace pre-adsorbed DNA either, indicating a strongly kinetically controlled system. Thiolated DNA can be attached at a low density on the AuNPs with a BSA corona. The BSA corona did not facilitate the hybridization of the conjugated DNA, while a smaller peptide, glutathione allowed faster hybridization. Overall, proteins increase the colloidal stability of AuNPs, and they do not perturb the gold-thiol bond in the DNA conjugate, although a large protein corona may inhibit the hybridization function of DNA.

Biosensor Based Immunoassay: A New Approach for Serotyping of Toxoplasma gondii

“…This approach takes advantage of the strong binding of BSA to citrate AuNPs by electrostatic interactions [ 32 ] and possibly also by chemisorption through many cysteine residues in the protein. BSA conjugates with AuNPs show high colloidal stability against salt, acid and base addition [ 33 ]. Moreover, GRA6II-BSA was used as an antigen to produce mouse immunosera; therefore, it is expected to have a stronger affinity of these probes to the mouse antibodies in immunosera used in the study.…”

Size and macromolecule stabilizer–dependent performance of gold colloids in immuno-PCR

“…Zeta potential measures the changes in surface charge of the nanoparticles before and after the surface functionalization. The loading of anionic biomacromolecules such as ODN is well-documented to increase the net surface charge of nanoparticles [31,32].…”

“…BSA is a well-studied protein that is cost-efficient and has been well explored as a GNP stabilizer for various biological applications [34]. BSA-stabilized GNPs have shown great stability in harsh pH conditions and in the presence of salts [32]. Streptavidin and ODN-loaded 15-nm GNPs were prepared in the presence of BSA and were analyzed for their net size and surface charge (Fig.…”

Bibliometric landscape of the researches on protein corona of nanoparticles

“…Since K. A. Dawson et al proposed the concept of protein corona in 2007 [31], many efforts have been made in this region. The protein corona formation behaviors and mechanisms of lipid-based [32], polymeric [33], metal [34] silica [35] and other nanoparticles [36][37][38] have been comprehensively explored. With these works, relatively profound understanding of protein corona formation phenomenon is obtained.…”