Nanotechnology-based water safety: Carbon nanotubes detecting copper ions in a water purification plant.

Is Your Tap Water Safe? How Nanotechnology Can Detect Copper Contamination

Nico Varela in Tech & Innovation December 2025 • 4 min read.

"Discover how scientists are using advanced nanotechnology to create highly sensitive sensors that detect copper in drinking water, ensuring safer water for your family."

For years, concerns about heavy metals in our water supply have grown as these toxins threaten both aquatic life and human well-being. Heavy metals are non-biodegradable, accumulating in the food chain through plants and animals, and potentially causing severe health issues if they enter our respiratory systems. These contaminants have been linked to disruptions in kidney function, bone health, and the central nervous system.

Copper, while essential in trace amounts, becomes toxic at elevated concentrations. Industries such as metal cleaning, plating, and fertilizer production contribute to copper pollution in water streams. The Safe Drinking Water Act sets a limit of 1.3 mg/dm³ for copper in drinking water, highlighting the need for effective monitoring and removal technologies.

Now, nanotechnology offers a promising solution. Scientists are harnessing the unique properties of nanomaterials to develop highly sensitive sensors. This article explores how single-walled carbon nanotubes (SWCNTs) are being used to detect copper in water sources, providing a faster, more accurate way to ensure our drinking water is safe.

Nanotech to the Rescue: How Carbon Nanotubes Detect Copper

Nanotechnology-based water safety: Carbon nanotubes detecting copper ions in a water purification plant.

Carbon nanotubes, known for their exceptional strength, conductivity, and large surface area, are at the heart of this innovation. These tiny cylinders of carbon atoms can be modified with carboxylic acid functional groups, making them highly effective at binding to copper ions. This process forms the basis of a sensor that uses electrical impedance spectroscopy (EIS) to measure the presence of copper.

The sensor works by immobilizing these modified SWCNTs on a gold electrode. When copper ions are present in the water sample, they bind to the SWCNTs, causing a change in the electrical properties of the sensor. EIS measures this change, providing a quantitative measure of the copper concentration.

Here’s a breakdown of the key steps:

Functionalization: Carbon nanotubes are modified with carboxylic acid (COOH) groups to enhance their ability to bind copper ions.
Immobilization: The modified nanotubes are attached to a gold electrode using a self-assembled monolayer (SAM) technique.
Detection: Electrical impedance spectroscopy (EIS) is used to measure changes in the electrical properties of the electrode when copper ions bind to the nanotubes.

Researchers tested this sensor in water samples from Tabuk, Saudi Arabia, and compared the results to those obtained in a controlled buffer solution. The sensor demonstrated high sensitivity, detecting copper concentrations in the range of 10-300 ng/ml. Notably, the signal in Tabuk water was four times stronger than in the buffer solution, indicating the presence of other compounds that enhance copper binding. This confirms the potential for real-world application of this sensor technology.

The Future of Water Safety: Nanotechnology to the Rescue

This research showcases the potential of nanotechnology to revolutionize water quality monitoring. The SWCNT-based sensor offers a rapid, sensitive, and cost-effective method for detecting copper contamination, addressing a critical need for public health protection.

While further studies are needed to optimize the sensor and assess its performance in diverse water conditions, the findings are promising. This nanotechnology-driven approach can empower communities to monitor their water supply more effectively and take proactive measures to mitigate contamination risks.

As concerns about water quality continue to rise, innovations like this offer hope for a future where safe drinking water is accessible to all. The integration of nanotechnology into environmental monitoring signifies a major step forward in safeguarding our health and environment.

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: 10.4172/2157-7439.1000396, Alternate LINK

Title: Electrical Impedance Spectroscopy Using Single Wall Carbon Nanotubes Carboxlic Acid Functionalized: Detection Of Copper In Tabuk-Kingdom Of Saudi Arabia Water

Subject: Pharmaceutical Science

Journal: Journal of Nanomedicine & Nanotechnology

Publisher: OMICS Publishing Group

Authors: Saloua Helali, Nadra Bohli

Published: 2016-01-01

Everything You Need To Know

Why is copper in drinking water a concern?

Copper is a heavy metal that can be harmful to human health when present in high concentrations in drinking water. The Safe Drinking Water Act sets a limit of 1.3 mg/dm³ for copper to protect public health. Copper contamination in drinking water can come from various sources, including industrial activities like metal cleaning and fertilizer production, which can pollute water streams. Exposure to elevated levels of copper can lead to health issues affecting the kidneys, bones, and central nervous system. Therefore, detecting and monitoring copper levels in drinking water is essential to safeguard public health and ensure the safety of water supplies.

How do single-walled carbon nanotubes (SWCNTs) help in detecting copper?

Single-walled carbon nanotubes (SWCNTs) are used in sensors to detect copper because of their unique properties. SWCNTs are known for their exceptional strength, conductivity, and large surface area. Scientists modify these nanotubes with carboxylic acid functional groups, which allows them to bind effectively to copper ions. This binding is the basis for the sensor’s detection mechanism, as the change in the electrical properties of the SWCNTs when copper is present can be measured using electrical impedance spectroscopy (EIS). This method allows for the rapid and accurate detection of copper contamination in water samples.

What is Electrical Impedance Spectroscopy (EIS), and how does it relate to copper detection?

Electrical Impedance Spectroscopy (EIS) is a technique used to measure the presence of copper in water using sensors built with single-walled carbon nanotubes (SWCNTs). The process involves measuring changes in the electrical properties of the SWCNTs when copper ions bind to them. Modified SWCNTs are attached to a gold electrode. When copper ions are present in the water sample, they attach to the SWCNTs, causing a change in the electrode’s electrical properties. EIS measures this change and provides a quantitative measure of the copper concentration, which allows for an accurate and efficient method of detecting copper contamination.

How does the sensor using single-walled carbon nanotubes (SWCNTs) work?

The sensor operates through a series of steps. First, the single-walled carbon nanotubes (SWCNTs) are modified with carboxylic acid (COOH) groups to improve their ability to bind with copper ions. Next, these modified nanotubes are attached to a gold electrode using a self-assembled monolayer (SAM) technique. Finally, electrical impedance spectroscopy (EIS) is used to measure changes in the electrical properties of the electrode when copper ions bind to the SWCNTs. This binding alters the electrical characteristics, which the EIS detects to quantify the copper concentration.

Why is this nanotechnology-based sensor significant for water safety?

The use of single-walled carbon nanotubes (SWCNTs) in sensors for water quality monitoring is significant because it offers a rapid, sensitive, and cost-effective method for detecting copper contamination. This technology addresses a critical need for protecting public health by providing a way to monitor water supplies for copper contamination quickly and accurately. The sensors can detect copper concentrations in the range of 10-300 ng/ml, which is important because copper, while essential in trace amounts, can become toxic at higher concentrations. The ability to quickly and accurately detect copper is essential for water safety.