Synthesis, properties, and optical applications of noble metal nanoparticle-biomolecule conjugates

Abstract

Noble metal nanoparticles, such as gold or silver nanoparticles and nanorods, exhibit unique photonic, electronic and catalytic properties. Functionalization of noble metal nanoparticles with biomolecules (e.g., protein and DNA) produces systems that possess numerous applications in catalysis, delivery, therapy, imaging, sensing, constructing nanostructures and controlling the structure of biomolecules. In this paper, the recent development of noble metal nanoparticle-biomolecule conjugates is reviewed from the following three aspects: (1) synthesis of noble metal nanoparticle-biomolecule systems by electrostatic adsorption, direct chemisorption of thiol derivatives, covalent binding through bifunctional linkers and specific affinity interactions; (2) the photonic properties and bioactivation of noble metal nanoparticle-biomolecule conjugates; and (3) the optical applications of such systems in biosensors, and medical imaging, diagnosis, and therapy. The conjugation of Au and Ag nanoparticles with biomolecules and the most recent optical applications of the resulting systems have been focused on. [4,5,8] are widely used to construct structures that possess unique electric, photonic and catalytic properties such as local surface plasmon resonance (LSPR) [7,[9][10][11], surface-enhanced Raman scattering (SERS) [12], and surface-enhanced fluorescence (SEF) [13,14]. There are two fundamental strategies used to prepare nanoparticles: bottom-up and top-down. The bottomup approach is a basic technique to prepare the metal nanoparticles by reducing their ions and the growth of the nanoparticles is usually stopped by an agent such as a surfactant or stabilizer. Bottom-up techniques include chemical reduction [15][16][17], photochemical reduction [18], electrochemical reduction [19], and templating [20] and thermal methods [21,22]. Bottom-up methods allow large-scale synthesis of the nanoparticles, but an obvious disadvantage is that the nanoparticles are usually of non-uniform size and shape compared with those produced by a top-down method. The top-down approach involves removing material from the bulk substrate to leave behind the desired nanostructures. Common top-down methods include photolithography, electron beam lithography, and nanosphere lithography (NSL) [23,24].Many biomolecules including proteins/enzymes/oligopeptides [7,25], antibody/antigens [1,26], biotin/streptavidin [23,24], and DNA/oligonucleotides/aptamers [6] have been immobilized on the surface of nanoparticles to form noble metal nanoparticle-biomolecule conjugates. The similar size of nanoparticles and biomolecules makes them rela-

Preparation and characterization of poly(ethylene glycol) stabilized nano silver particles by a mechanochemical assisted ball mill process

“…1,2 These noble metallic nanoparticles contribute the significant role in a wide range of fields such as biomedical, pharmaceutical, cosmetic, drug delivery, antimicrobial, energy and electronic devices etc. 1,2 Among the noble nanoparticles, nano silver particle has gained very good prominence as antimicrobial agent and it has also been used in the clothing, food industries, sunscreens, wounds dressing, and cosmetics. [3][4][5] Furthermore, silver nanoparticles with polymers have gained popularity in an ointment, wound dressing, and other applications.…”

“…Nanotechnology has been used immensely in the synthesis of noble metallic nanoparticles for advanced technological applications. 1,2 These noble metallic nanoparticles contribute the significant role in a wide range of fields such as biomedical, pharmaceutical, cosmetic, drug delivery, antimicrobial, energy and electronic devices etc. 1,2 Among the noble nanoparticles, nano silver particle has gained very good prominence as antimicrobial agent and it has also been used in the clothing, food industries, sunscreens, wounds dressing, and cosmetics.…”

Nanoparticles Carrying Biological Molecules: Recent Advances and Applications

“…However, molecular orientations of the physically bound biomolecules are difficult to control. By introducing specific functional groups on the nanoparticles such as avidin, biomolecules can bound onto the nanoparticles more effectively through affinity interactions (Zhang Y. et al, 2012). Avidin is a glycoprotein composed of four identical subunits which have high specificity and affinity towards biotin, resulted in a strong affinity interaction.…”

“…If no thiolated residues available in the native biomolecules, the thiol group can be introduced chemically onto the outer part of biomolecules using Traut`s reagent (2-aminothiolane) to allow biomolecules-NP interaction (Fig. 4b) (De M. et al, 2008;Zhang Y. et al, 2012). The noble metal nanoparticle, particularly gold (Au) nanoparticle is highly reactive toward thiol group, thus forming a superior Au-S bond.…”

Nanocomposite of montmorillonite and silver nanoparticles: Characterization and application in catalytic reduction of 4-nitrophenol

“…They can be used in different fields of chemistry as effective catalysts [18,19], excellent antibacterial materials [20,21], in medicine [22], and also in construction of new sensors for analytical applications [23,24].…”