Gold nanorod libraries enhancement for optical imaging

• One-step hydrothermal synthesis of TOMAC (Aliquat 336) stabilized gold nanorods.
• Processing parameters dependent alteration of nanostructures (NSs) shapes.
• Kinetically controlled reaction for the growth of NRs (high energy facets {110}).
• Visible fluorescence at 410 nm attributed to the ligand–metal charge transition.
• Highly elongated and mono-dispersed NRs beneficial in single-particle measurements.

Efficient far-field coupling of longitudinal plasmon modes of gold nanorods makes them prospective for optical imaging. A facile one-step hydrothermal synthesis of stabilized gold nanorods in an aqueous solution at 85 °C is reported. High aspect ratio of these nanorods ranging from 10 to 57 is achieved using methyltrioctylammonium chloride (TOMAC) as a phase transfer reagent. The growth of {100} and {110} facets being more favorable to conception is facilitated via the capping agent (TOMAC). These highly elongated nanorods reveal visible luminescence at around 410 nm, which is attributed to the ligand–metal charge transition mechanism. We affirm that such plasmonic nanorods acquiring superior nonlinear optical properties can be used as a vehicle for single-particle measurements.