Synthesis, capping and binding of colloidal gold nanoparticles to proteins

Abstract

Bovine serum albumin (BSA) was used as a stabilizing agent and biofunctionalized layer for water-dispersed gold nanoparticles (NPs) synthesized from metal precursor HAuCl 4. The BSA binding to gold NPs was characterized qualitatively and quantitatively by transmission electron microscopy, UV-VIS and FTIR spectrophotometers. HER2 (human epidermal growth factor receptor 2) specific phage antibodies were attached to BSA stabilized gold NPs to form a gold–antibody complex. An ELISA (enzyme-linked immunosorbent assay) test was done to confirm the bioactivity of antibodies attached to gold NPs.

Synthesis and characterization of jacalin-gold nanoparticles conjugates as specific markers for cancer cells

“…In contrast to AuNPs, the AuNPs/jacalin-FITC nanoconjugate presented a shadow around the particle surface, which may be an indicative of the formation of a protein layer around the AuNPs. This phenomenon has been observed by other authors in the study of protein-conjugated nanoparticles [12,33,34].…”

“…The individual spectral features of jacalin and the nanoparticles appear in the spectrum of the nanoconjugate at approximately 280 and 523 nm, respectively, even after washing. It is possible to observe a slightly red shift on the AuNPs band compared with its individual spectra, which may be indicative of its surface modification [12]. The AuNPs/jacalin nanoconjugated also presented higher stability at neutral pH than free AuNPs.…”

“…Nanoparticles may be accumulated in the tumor by a passive targeting by taking advantage of the enhanced permeability and retention effect (EPR effect) [9][10][11]. On the other hand, the active targeting may be achieved via functionalization of the nanoparticle surfaces [11] with specific proteins [12], peptides [13], aptamers [14] and antibodies [15]. Therefore, conjugating biomolecules to gold nanoparticles may provide nanomaterials with additional interaction capabilities [16].…”

Growth of silver-coated gold nanoshells with enhanced linear and nonlinear optical responses

“…Metallic nanoparticles have fascinated researchers for several decades because of their wide range of potential applications (Patolsky et al 2004;Narayanan and El-Sayed 2005;Park et al 2007;Aslan et al 2007;Le et al 2008;Ashayer et al 2010;Nghiem et al 2010;Pyne et al 2011;Chu et al 2011;Sun et al 2014a, b). The properties of metallic nanoparticles are critically dependent on their composition, shape, geometry (Link and El-Sayed 2000;Jackson et al 2003;Sosa et al 2003;Cui et al 2006;Karvianto and Chow 2012).…”

Surface plasmon resonances of protein-conjugated gold nanoparticles on graphitic substrates

“…For the case of AuNP/BSA/water, A ¼ 0.61. 19,24 The increase in A indicates that the presence of the protein enhances the effect of the finite NP size on the cross section. Figure 2(a) shows that the absorption spectrum has similar magnitude regardless of the presence of BSA, although the protein reduces the width of the peak to some extent.…”