Improvements in Gold Nanorod Biocompatibility with Sodium Dodecyl Sulfate Stabilization

Abstract

Due to their well-defined plasmonic properties, gold nanorods (GNRs) can be fabricated with optimal light absorption in the near-infrared region of the electromagnetic spectrum, which make them suitable for cancer-related theranostic applications. However, their controversial safety profile, as a result of surfactant stabilization during synthesis, limits their clinical translation. We report a facile method to improve GNR biocompatibility through the presence of sodium dodecyl sulfate (SDS). GNRs (120 × 40 nm) were synthesized through a seed-mediated approach, using cetyltrimethylammonium bromide (CTAB) as a cationic surfactant to direct the growth of nanorods and stabilize the particles. Post-synthesis, SDS was used as an exchange ligand to modify the net surface charge of the particles from positive to negative while maintaining rod stability in an aqueous environment. GNR cytotoxic effects, as well as the mechanisms of their cellular uptake, were examined in two different cancer cell lines, Lewis lung carcinoma (LLC) and HeLa cells. We not only found a significant dose-dependent effect of GNR treatment on cell viability but also a time-dependent effect of GNR surfactant charge on cytotoxicity over the two cell lines. Our results promote a better understanding of how we can mediate the undesired consequences of GNR synthesis byproducts when exposed to a living organism, which so far has limited GNR use in cancer theranostics.

Hyaluronate-Thiol Passivation Enhances Gold Nanoparticle Peritumoral Distribution When Administered Intratumorally in Lung Cancer

“…Evaluating the tumoral distribution of a drug or particle-drug conjugate is an important variable that is often neglected, as most drugs are assumed to distribute homogeneously into a tumor [ 22 ]. In previous studies, we demonstrate that GNP cellular uptake [ 23 , 24 ], as well as intratumoral distribution and retention [ 25 , 26 ], is strongly influenced by surface chemistry. We have shown that when GNPs are surface passivated with a bovine serum albumin (BSA) protein layer, internalization of the particles into cancer cells occurs through larger vesicle formation with reduced gold content per cell, and when injected intratumorally in a murine lung cancer model, the BSA passivated particles diffuse more overtime throughout the tumor tissue [ 25 ].…”

Hyaluronate-Thiol Passivation Enhances Gold Nanoparticle Peritumoral Distribution When Administered Intratumorally in Lung Cancer

“…Evaluating the tumoral distribution of a drug or particle-drug conjugate is an important variable that is often neglected, as most drugs are assumed to distribute homogeneously into a tumor [19]. In previous studies, we demonstrate that GNP cellular uptake [20,21], as well as intratumoral distribution and retention [22,23], is strongly influenced by surface chemistry. We have shown that when GNPs are surface passivated with a bovine serum albumin (BSA) protein layer, internalization of the particles into cancer cells occurs through larger vesicle formation with reduced gold content per cell, and when injected intratumorally in a murine lung cancer model, the BSA passivated particles diffuse more overtime throughout the tumor tissue [22].…”

Gold Nanorods Function as Near-Infrared Light-Activated Microheaters for In Situ Curing of Injectable Hydrogel Therapies

“…The precipitated AuNRs were redispersed in 5 mL of deionized water for further use. For cell culture samples, the cytotoxicity of AuNRs caused by CTAB was reduced by using SDS as an overcoating agent to stabilize the AuNR surface . The AuNR solution was precipitated, and the AuNR particles were resuspended in SDS solution at 10 mM.…”