Sona's Platform Technology: Uniquely biocompatible gold nanorods (GNRs)
What are gold nanorods
- Rod-shaped nanoparticles made of gold
- Sizes of 10 to 100 nanometers in length
- Nanometer is one-billionth of a meter
- Produced by chemical synthesis
- Can be conjugated to different molecules
Validated in humans.
Sona’s CTAB-free gold nanorods have now been tested in a first-in-human clinical study. In October 2025, THT delivered an 80% overall response rate in 10 immunotherapy-resistant late-stage melanoma patients. Human tissue analysis at Dalhousie University confirmed NK cell infiltration, macrophage activation, and PD-L1 upregulation in representative patient samples. The technology is no longer theoretical.
Validated in humans. Sona’s CTAB-free gold nanorods have now been tested in a first-in-human clinical study. In October 2025, THT delivered an 80% overall response rate in 10 immunotherapy-resistant late-stage melanoma patients. Human tissue analysis at Dalhousie University confirmed NK cell infiltration, macrophage activation, and PD-L1 upregulation in representative patient samples. The technology is no longer theoretical.
overall response rate in 10 immunotherapy-resistant late-stage melanoma patients
Uses of gold nanorods
Their surface chemistry and physical properties make gold nanorods ideally suited for a variety of applications. Sona GNRs, with the added benefit of being biocompatible, are shaping advancements across a number of key areas.
Clinical Applications
- Photothermal therapy
- Tumor targeting activity
- Anti-bacterial activity
- Drug delivery vehicle
Diagnostics
- Diagnostic markers for imaging
- Immunoassay and biosensing
Sona's GNR in Lateral Flow Assays (LFA's) as diagnostic tools.
Gold Nanorods
Gold nanorods (GNRs) are small particles whose surface plasmon resonance (SPR) frequencies can be altered by modifying their length and width, giving them properties useful in a host of applications, including diagnostics, optical biomedical imaging, and photothermal therapies, to name a few. One of the major barriers in the application of GNR-based materials, however, especially for in-vivo applications such as hyperthermal cancer treatment, is the presence of cetyltrimethylammonium bromide (CTAB), a cytotoxic, cationic surfactant used exclusively in the large scale synthesis of GNRs. CTAB attacks and kills cells in the body in 2 ways: by creating nanoscale holes within affected cell membranes and depriving cells of energy, ultimately killing the cell in both cases.
The concentration of CTAB that is most often used in the synthesis of gold nanorods is typically 100 times its critical concentration, meaning a significant amount of CTAB remains in the bulk of the solution after the GNRs are made. A number of methods have been used to remove or partially exchange the CTAB, however, these surface modified GNRs are often still contaminated with residual CTAB.
For GNRs to be safely and more readily integrated into in vivo applications, removal of CTAB is essential. This is where Sona’s patented technology comes in. Our revolutionary process of GNR synthesis completely eliminates CTAB from the equation all together!
Limitations of other nanoparticles and Sona's GNR technology solution
Toxicity
Other gold nanorod’s require CTAB (cyltrimethylammonium bromide) for their manufacture process. CTAB is a known toxin that can kill cells and is therefore less suitable for in-vivo therapies.
Uniquely Biocompatible
Sona surfactant uses no CTAB
- Can convert infrared light energy into heat in the same way as CTAB-based GNRs.
- Potentially more suitable for use in the body.
Shape
Other nanoparticle shapes take longer to heat.
Nanospheres, nanostars or nanoshells have:
- Limited surface area
- Limited stability
- Limited penetration depth into cells
Limited ability to tune for resonance
Shaped as rods
Nanorods by Sona have
- Variety of lengths and widths to increase surface area
- Long shelf life and stable surface properties
Fastest conversion of non-thermal light energy into heat.
Sona's GNR Technology Assessment: U.S. Nanotechnology Characterization Laboratory
Sona Nanotech to Showcase its THT Cancer Therapy at NCL 20th Anniversary Symposium and Provides Corporate Update
No endotoxin or microbial contamination detected in Sona’s GNRs
Getting the approval of regulators to run clinical trials for targeted hyperthermia therapy (THT) will require a mountain of compelling data. These NCL assessments of the biocompatibility of our core, gold nanorod technology, coupled with the existing small animal study data for THT will provide us with a great base on which to build in the coming months. As with the NCL’s January assessment of three earlier batches of Sona’s gold nanorods, this new assessment did not detect any endotoxins or microbial contamination.
Sona Nanotech Updates on Dalhousie Efficacy Study and New NCL Results
A significant reduction in free surfactant levels in nanorod dispersions, with the average dropping from 230.7ug/mL in prior assessed batches to 34.6ug/mL in the batches following process changes.
Sona’s laboratory has undertaken a manufacturing enhancement program in preparation for the production of the gold nanorods necessary for our anticipated pre-clinical trials and studies. This program has resulted in improved yields and reduced surfactant levels with no loss in stability or biocompatibility, as evidenced by these additional excellent NCL assessment results which we were very pleased to receive.
Sona GNRs could unlock the power of in-vivo applications
Our advancements in gold nanotechnology are transforming the diagnostic, scientific, and medical treatment markets.
Our gold nanorod products offer a highly functionalized and robust manufacturing process.
- Lengths from 25-60 nm
- Typical widths from 10-15 nm
- CTAB free & Bio-Compatible
- Wide colour spectrum
- Long shelf life
- Functionalized surface properties
What makes Sona Nanotech's gold nanorods unique?
Sona’s gold nanorods are CTAB-free, meaning they are manufactured without the cytotoxic surfactant used in conventional gold nanorod production. This makes them uniquely biocompatible for use in humans. They have been validated by the NCI Nanotechnology Characterization Laboratory and used in a completed first-in-human clinical study.
What is CTAB and why does removing it matter?
CTAB (cetyltrimethylammonium bromide) is a surfactant used in conventional gold nanorod production that is toxic to human cells. Sona’s CTAB-free synthesis process removes this barrier, enabling gold nanorods that are safe for direct injection into human tissue. This is the foundational differentiation of Sona’s platform.