Session: 14-10-01: Micro/Nanofluidics 2025 I

Paper Number: 167304

Nanopore-Based Sensing Platform for Real-Time Detection of Heavy Metals: A Simulation Approach 

The urgent need for advanced detection technologies is underscored by the severe environmental and health risks posed by heavy metals. Naturally occurring elements, such as lead, mercury, cadmium, and arsenic, have been extensively used in various industrial applications and consumer products, yet they are highly toxic and persistent in the environment. These metals contaminate environmental media, including water, soil, and living organisms, and once introduced into ecosystems, they do not degrade but instead accumulate through the food chain. This persistent accumulation poses significant risks to both human health and the environment. Prolonged exposure to these heavy metals is associated with a wide range of health complications, including neurological damage, kidney and liver dysfunction, developmental disorders, and cancer, making the need for effective detection and monitoring technologies even more urgent.

 

Current analytical methods for detecting heavy metals, such as atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectrometry (ICP-MS), are considered gold standards due to their high sensitivity and specificity. ICP-MS enables precise detection of metal ions through plasma-based ionization coupled with mass spectrometry, offering high accuracy in analyzing complex sample matrices. However, these methods are often costly, complex, and time-consuming, requiring extensive sample preparation, specialized reagents, and sophisticated instrumentation. As a result, they are not ideal for real-time or on-site monitoring, where rapid and cost-effective analysis is essential. Sample preparation and analysis in these methods can take hours, limiting their applicability in urgent or large-scale environmental monitoring scenarios.

 

Nanopore technology presents a promising alternative for real-time detection of heavy metals. In fact, we have introduced a novel nanopore-based sensing platform that utilizes dual in-plane nanopores and a nanochannel flight tube. This platform enables label-free, precise discrimination of individual molecules, achieving high accuracy by measuring their flight time through the nanopores. The discrimination mechanism for different molecules is based on nanoscale electrophoresis, where the Time of Flight (ToF) is evaluated by measuring the passage time of a single molecule through the nanochannel column. The platform demonstrated an identification accuracy of 94% for four deoxyribonucleoside monophosphates (dNMPs) using a 5 µm nanochannel column, with accuracy dependent on column length.

 

In this study, we apply this innovative nanopore sensing technology to detect heavy metals in environmental samples. To assess the feasibility of this approach, we first use COMSOL simulations to model the electrokinetic behavior of charged particles and their interactions with heavy metals within a nanopore structure. The simulation integrates physical modules such as Electrostatics, Transport of Diluted Species, and Creeping Flow to examine the potential of the nanopore-based sensor for real-time heavy metal detection. This study aims to provide a more cost-effective, rapid, and portable alternative to traditional detection methods, opening the door to advanced environmental monitoring and early detection of heavy metal contamination.

Presenting Author: Junseo Choi Texas State University

Presenting Author Biography: Junseo Choi is an assistant professor in the Department of Engineering Technology at Texas State University. He earned his B.S. and M.S. in Chemical and Advanced Materials Engineering from Kyung Hee University in South Korea in 2004 and 2006, respectively, and completed his Ph.D. in Mechanical Engineering at Louisiana State University in 2013.

Authors:

Junseo Choi Texas State University
Devanda Lek Texas State University
In-Hyouk Song Texas State University
Byoung Hee You Texas State University