Gold and silver nanoparticles attacking cancer cells

Silver & Gold Nanoparticles: A New Weapon in the Fight Against Cancer?

Samir D’Costa in Health & Wellness December 2025 • 4 min read.

"Researchers explore how combining silver and gold nanoparticles can selectively target and destroy cancer cells, opening doors to less toxic cancer treatments."

Cancer treatment often feels like a balancing act – trying to eliminate cancerous cells without severely damaging the body's healthy tissues. Traditional methods like chemotherapy and radiation, while effective, can come with harsh side effects that significantly impact a patient's quality of life. This has driven researchers to explore more targeted and less toxic approaches to cancer therapy.

Nanotechnology, the manipulation of matter on an atomic and molecular scale, offers promising avenues for developing such treatments. In particular, nanoparticles – tiny particles measuring just billionths of a meter – can be engineered to interact with biological systems in unique ways. Scientists are investigating the potential of nanoparticles to deliver drugs directly to cancer cells, enhance imaging techniques, and even directly destroy tumors.

Recent research focuses on bimetallic nanoparticles (BNPs), which combine two different metals into a single nanoparticle. These BNPs can possess unique properties that are superior to those of nanoparticles made from a single metal. One promising area of research involves combining silver (Ag) and gold (Au) into BNPs to target and destroy cancer cells. This article explores how these Ag/Au BNPs work, their potential benefits, and the remaining challenges in bringing this technology to the forefront of cancer treatment.

How Ag/Au Nanoparticles Selectively Kill Cancer Cells

Gold and silver nanoparticles attacking cancer cells

The study highlights that Ag/Au BNPs can be synthesized as “alloys” using a chemical reduction method involving tryptophan, an amino acid. The key is finding the right balance of silver and gold, along with the appropriate amount of tryptophan, to maximize the nanoparticles' effectiveness against cancer cells while minimizing harm to healthy cells.

Researchers tested different ratios of Ag/Au BNPs on various cancer cell lines, including colon cancer, breast cancer, and liver cancer cells. They found that Ag/Au nanoparticles with a metal ratio of 3:1 (more silver than gold) exhibited the most potent anti-tumor effects. Importantly, these nanoparticles showed significantly reduced toxicity in non-cancerous cell lines, suggesting a selective action against cancer.

Metal Ratio: A 3:1 silver-to-gold ratio appears to be optimal for targeting cancer cells.
Tryptophan's Role: Tryptophan helps stabilize the nanoparticles and may contribute to their selective toxicity.
Selective Toxicity: BNPs show a preference for cancer cells over healthy cells, potentially reducing side effects.

To understand how these nanoparticles selectively kill cancer cells, the researchers investigated their impact on key cellular processes. They discovered that Ag/Au BNPs induce apoptosis, or programmed cell death, in cancer cells by activating specific pathways: These pathways involve genes like p53, caspase-3, Bax, and Bcl-2, which play critical roles in regulating cell cycle, DNA repair, and apoptosis. By manipulating these pathways, the nanoparticles effectively trigger self-destruction in cancer cells.

The Future of Nanoparticle Cancer Therapy

This research provides a promising step towards developing more targeted and less toxic cancer therapies. By carefully controlling the composition and properties of Ag/Au BNPs, scientists may be able to create treatments that selectively destroy cancer cells while sparing healthy tissues.

While these findings are encouraging, further research is needed to fully understand the long-term effects and potential risks of using Ag/Au BNPs in humans. Future studies will focus on:

<ul><li>In vivo studies: Testing the nanoparticles in living organisms to assess their efficacy and safety.</li><li>Targeted delivery: Enhancing the nanoparticles' ability to specifically target cancer cells.</li><li>Personalized medicine: Tailoring nanoparticle treatments to individual patients based on their cancer type and genetic makeup.</li></ul>

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1080/21691401.2018.1495645, Alternate LINK

Title: Ag/Au Bimetallic Nanoparticles Induce Apoptosis In Human Cancer Cell Lines Via P53, Caspase-3 And Bax/Bcl-2 Pathways

Subject: Pharmaceutical Science

Journal: Artificial Cells, Nanomedicine, and Biotechnology

Publisher: Informa UK Limited

Authors: Hector Katifelis, Anna Lyberopoulou, Iuliia Mukha, Nadiia Vityuk, Gallina Grodzyuk, George E. Theodoropoulos, Efstathios P. Efstathopoulos, Maria Gazouli

Published: 2018-10-29

Everything You Need To Know

How do silver and gold bimetallic nanoparticles (Ag/Au BNPs) specifically target and destroy cancer cells?

Silver and gold bimetallic nanoparticles (Ag/Au BNPs) are synthesized as alloys using a chemical reduction method involving tryptophan. An optimal ratio of silver to gold, such as 3:1, is crucial for maximizing effectiveness against cancer cells while minimizing harm to healthy cells. These nanoparticles induce apoptosis (programmed cell death) in cancer cells by activating specific pathways involving genes like p53, caspase-3, Bax, and Bcl-2, which regulate cell cycle, DNA repair, and apoptosis. This targeted approach allows the nanoparticles to selectively trigger self-destruction in cancer cells, reducing toxicity to non-cancerous cells.

What is the role of tryptophan in the creation and function of silver and gold bimetallic nanoparticles (Ag/Au BNPs)?

Tryptophan plays a crucial role in the synthesis of silver and gold bimetallic nanoparticles (Ag/Au BNPs) by aiding in the chemical reduction method used to create the nanoparticles in alloy form. Furthermore, tryptophan helps to stabilize the nanoparticles, ensuring they maintain their structure and effectiveness. It may also contribute to the selective toxicity of the Ag/Au BNPs, enhancing their ability to target cancer cells while minimizing harm to healthy cells. The precise mechanisms by which tryptophan contributes to selective toxicity warrant further investigation to fully understand its function.

Why are researchers exploring silver and gold bimetallic nanoparticles (Ag/Au BNPs) as a potential cancer treatment instead of traditional methods like chemotherapy and radiation?

Traditional cancer treatments such as chemotherapy and radiation, while effective, often come with harsh side effects that significantly impact a patient's quality of life. Silver and gold bimetallic nanoparticles (Ag/Au BNPs) offer a more targeted approach by selectively inducing apoptosis (cell death) in cancer cells while minimizing damage to healthy tissues. This selectivity is achieved through specific pathways involving genes like p53, caspase-3, Bax, and Bcl-2. By manipulating these pathways, nanoparticles trigger self-destruction only in cancer cells, potentially reducing the severe side effects associated with traditional cancer treatments. Nanotechnology provides avenues for precise interaction with biological systems, enhancing treatment efficacy and reducing toxicity.

What are the genes involved in the apoptosis pathway activated by silver and gold bimetallic nanoparticles (Ag/Au BNPs), and what roles do they play?

Silver and gold bimetallic nanoparticles (Ag/Au BNPs) induce apoptosis (programmed cell death) in cancer cells by activating specific pathways involving several key genes. These genes include p53, which plays a crucial role in regulating the cell cycle and DNA repair. Caspase-3 is an executioner caspase that initiates the final steps of apoptosis. Bax promotes apoptosis by disrupting the mitochondrial membrane, while Bcl-2 inhibits apoptosis and promotes cell survival. By manipulating the balance between pro-apoptotic (e.g., Bax) and anti-apoptotic (e.g., Bcl-2) factors, the nanoparticles effectively trigger self-destruction in cancer cells. Disrupting the balance is vital for effective cancer treatment using this method.

What are the implications of using a specific metal ratio, such as 3:1 silver-to-gold, in bimetallic nanoparticles (Ag/Au BNPs) for cancer treatment?

Using a specific metal ratio, such as 3:1 silver-to-gold in bimetallic nanoparticles (Ag/Au BNPs), is critical for optimizing the nanoparticles' effectiveness against cancer cells while minimizing harm to healthy cells. Research indicates that this ratio exhibits the most potent anti-tumor effects. The balance between silver and gold influences the nanoparticles' surface properties, reactivity, and interaction with biological systems. Deviating from this optimal ratio may reduce the nanoparticles' selectivity for cancer cells, potentially leading to increased toxicity in non-cancerous tissues. Therefore, precise control over the metal ratio is essential for achieving the desired therapeutic outcome.