Morphological control of seedlessly-synthesized gold nanorods using binary surfactants

Abstract

High purity gold nanorods (AuNRs) with tunable morphology have been synthesized through a binary-surfactant seedless method, which enables the formation of monocrystalline AuNRs with diameters between 7 and 35 nm. The protocol has high shape yield and monodispersity, demonstrating good reproducibility and scalability allowing synthesis of batches 0.5 l in volume. Morphological control has been achieved through the adjustment of the molar concentrations of cetyltrimethylammonium bromide and sodium oleate in the growth solution, providing fine tuning of the optical scattering and absorbance properties of the AuNRs across the visible and NIR spectrum. Sodium oleate was found to provide greatest control over the aspect ratio (and hence optical properties) with concentration changes between 10 and 23 mM leading to variation in the aspect ratio between 2.8 and 4.8. Changes in the geometry of the end-caps were also observed as a result of manipulating the two surfactant concentrations.

Rational screening of biomineralisation peptides for colour-selected one-pot gold nanoparticle syntheses

“…25,26 The wavelength of the AuNP LSPR is dependent on the shape, size, and agglomeration state. [27][28][29] The peptide screening technique uses a coherent membrane-supported peptide array library 30,31 consisting of AuNP binding peptides. 32 Each spot was able to capture synthesised AuNPs and through the accompanying colour change indicate the unique optical properties of bound AuNPs (Fig.…”

Stimuli‐Responsive Release of Antimicrobials Using Hybrid Inorganic Nanoparticle‐Associated Drug‐Delivery Systems

“…The indiscriminate nature of encapsulation allows for a wide range of NPs with distinct properties to be chosen for specific applications. For example, in the light‐stimulated release of therapeutics, the liposomal encapsulation of anisotropic Au NPs such as Au nanorods, Au nanostars, and Au nanoprisms with strong absorbance in the NIR region, where tissues and biological fluids minimally absorb, allows for deeper light penetration through human tissues . However, further technique development is required to provide confidence in the encapsulation of anisotropic NPs, as there is little direct evidence, through TEM imaging, to indicate that the large scale uniform incorporation of the NPs into the liposomes has been achieved.…”

Role of gold nanoparticles in advanced biomedical applications

“…Different size and shape GNPs have been used by many researchers in diverse biomedical applications. 92,98,99 As discussed in other sections of this review, radioactive and simple gold nanostructures have been used in many advanced biomedical applications. 100 Alkilany and co-workers studied the toxicity of colloidal GNPs.…”

“…220 A variety of gold nanostructures, e.g., gold nanoshells, nanocages, nanorods and nanostars, can be used for dark eld cell imaging. 6,98,221 Additionally, gold nanostructures are well known for SERS and have been utilized for Raman signal based imaging of biological cells. 6,22 The quality of the formed images is distinctly comparable with that of uorescence images.…”