Peptide-functionalized gold nanoparticles: versatile biomaterials for diagnostic and therapeutic applications

Abstract

Colloidal gold solutions have been used for centuries in a wide variety of applications including staining glass and in the colouring of ceramics. More recently, gold nanoparticles (GNPs) have been studied extensively due to their interesting size-dependent electronic and optical properties. GNPs can be functionalized easily with biomolecules that contain thiols, amines, or even phosphine moieties. For example, the reaction of thiol-containing peptides with GNPs has been used extensively to prepare novel hybrid materials for biomedical applications. A range of different types of peptides can be used to access biomaterials that are designed to perform a specific role such as cancer cell targeting. In addition, specific peptide sequences that are responsive to external stimuli (e.g. temperature or pH) can be used to stabilise / destabilise the aggregation of colloidal GNPs. Such systems have exciting potential applications in the field of colorimetric sensing (including bio-sensing) and in targeted drug delivery platforms. In this review, we will give an overview of the current methods used for preparing peptide functionalized GNPs, and we will discuss their key properties outlining the 2 various applications of this class of biomaterial. In particular, the potential applications of peptide functionalized GNPs in areas of sensing and targeted drug delivery will be discussed.

Targeting Integrins in Cancer Nanomedicine: Applications in Cancer Diagnosis and Therapy

“…Among the high-Z metals, gold (Au, Z = 79) is the element most often used as an NP platform. Gold NPs (AuNPs) possess several advantages over other materials: (i) good biocompatibility, as indicated by the ease with which AuNPs enter the human body without inducing harmful effects [177]; (ii) the straightforward nature of the synthesis of different-sized AuNPs [178]; and (iii) the easy functionalization of AuNPs by conjugating ligands to its surface [179]. These characteristics have inspired individuals to conjugate integrin-targeted ligands to the surface of AuNPs, which illustrates the concept of "targeted radiosensitizers".…”

Plasmonic Material Engineering for Targeted Therapeutics

“…This allows for adding a high number of functionalization molecules to the particles per volume. The ease of functionalization of AuNPs, due to a favorable interaction between gold and the sulfur in thiols, has led to a multitude of added molecules such as various drugs, [ 40,41 ] miRNA [ 11 ] and siRNA, [ 18 ] DNA, [ 42 ] peptides, [ 43 ] and “stealth molecules” such as PEG molecules. [ 23 ] A challenge to consider if using metallic nanoparticles in vivo is the tendency to agglomerate when the particles are introduced into a saline solution due to the decrease in Debye length facilitated by the ions in solution.…”

Gold Nanoparticles and Nanorods in Nuclear Medicine: A Mini Review

“…AuNPs can be synthesized by means of several processes such as chemical, physical, and biological methods [24,[49][50][51]65]. A well-known bottom-up approach is a wet reduction in the presence of a capping agent [55,57,[59][60][61][62]64].…”

“…Consequently, it is positive to develop active targeting systems that can selectively identify specific cells or tissues, attaching specific ligands such as antibodies, aptamers, peptides, and so forth, on nanocarrier surfaces [48,49].Among others, the gold-based nanomaterials have amazing features that make them very suitable and valuable in nanomedicine. In fact, they show remarkable chemical-physical properties, such as an easy modifiable morphology/size/surface, modulable optical absorption and scattering, photothermal and photoacoustic enhancements, and a wide surface/volume ratio that is suitable for interaction with the environment [50][51][52][53]. The gold surface can be functionalized and linked with drugs [54-57] and biomolecules, such as enzymes, antibodies, DNA, and peptides to achieve a specific site [58][59][60][61][62][63][64][65][66], and they are also studied to develop innovative antibacterial systems [67][68][69][70].In the wide field of advanced materials that represent the frontier where gold-based materials and nuclear medicine meet, this review provides an updated scenario of the progress in this young research field, focusing on gold nanoparticles (AuNPs) and nanorods (AuNRs) used in diagnosis and therapy, as schematized in Figure 1.…”