
Stable and reproducible synthesis of gold nanorods for biomedical applications: a comprehensive study
Author(s) -
Awan Uzma Azeem,
Ali Shaukat,
Rehman Mehreen,
Zia Nashmia,
Sohaila Naz Syeda,
Ovais Muhammad,
Raza Abida
Publication year - 2018
Publication title -
iet nanobiotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.366
H-Index - 38
eISSN - 1751-875X
pISSN - 1751-8741
DOI - 10.1049/iet-nbt.2016.0220
Subject(s) - nanorod , surface plasmon resonance , nanotechnology , materials science , plasmon , nanoparticle , bromide , biomolecule , chemical stability , chemical engineering , chemistry , organic chemistry , optoelectronics , engineering
Gold nanorods (GNRs) are ideal choice in biomedical research due to their amenability of synthesis, tunable plasmonic properties, less toxicity and ease of detection but their diverse biological applications necessitate stable structure. Despite two decades' efforts made towards reproducible anisotropic structures synthesis, still the kinetic control during GNRs growth has not been achieved. This study is an attempt to apprehend thermodynamic and kinetic parameters for synthesising mono‐disperse, reproducible and highly stable GNRs with desired aspect ratios. Effects of various growth parameters and assay steps on the facile and reproducible synthesis of GNRs are analysed. GNRs' environmental and biological colloidal stability is studied through UV–Vis spectroscopy based particle instability parameter (PIP < 0.1). The authors hereby report GNRs with tunable longitudinal surface plasmon resonance (682–906 nm) having different aspect ratios (2.5–4.6) that are stable at 28–60°C; however, prolonged high temperature ( > 60°C) and alkaline pH can trigger colloidal instability. GNRs remain stable at higher salt concentration, physiological and slightly acidic pH. GNRs can be stored in 0.001 M cetyltrimethylammonium bromide for 3 months without compromising their stability. PEGylated GNRs are quite stable in cellular media solution (PIP < 0.1). With current optimised growth conditions, no aggregation at physiological pH and stability at high temperatures make GNRs an ideal candidate in biomedical applications.