Metalon® JG-106 Gold Nanoparticle Ink Powers a Low-Cost, High-Sensitivity Electrochemical Sensor for Isoniazid Detection
Printed electronics continues to expand its reach into clinical and point-of-care diagnostics, and a newly published study in Advanced Sensor Research offers a compelling demonstration of how the right conductive ink can transform a paper substrate into a high-performance analytical device.
In work led by Dr. Sri Ramulu Torati and Prof. Gymama Slaughter of Old Dominion University’s Center for Bioelectronics, researchers fabricated a scalable, paper-based electrochemical sensor for the sensitive detection of isoniazid (INZ) — a frontline antimicrobial agent used in tuberculosis therapy. The sensor architecture relies on a gold inkjet-printed electrode (GIPE) formulated from NovaCentrix’s Metalon® JG-106 gold nanoparticle ink, further modified with electrodeposited gold nanoparticles, chitosan, and multi-walled carbon nanotubes (MWCNTs).
Why This Matters
Tuberculosis remains one of the most pressing global health challenges, and isoniazid is among the most widely prescribed treatments. Reliable therapeutic drug monitoring is essential for ensuring patient safety, optimizing dosage, and minimizing hepatotoxicity. Conventional laboratory methods such as HPLC and mass spectrometry are accurate but expensive, slow, and unsuitable for the decentralized clinical environments where TB burden is highest. A paper-based electrochemical sensor offers a low-cost, disposable, and field-deployable alternative — provided the printed electrode delivers the conductivity, uniformity, and electrochemical stability required for trace-level analyte detection.
This study demonstrates that inkjet-printed gold electrodes, formed from NovaCentrix Metalon® JG-106, meet that bar.
The Role of NovaCentrix Metalon® JG-106
Metalon® JG-106 is a gold nanoparticle ink (30–50 nm particle size) developed for inkjet printing onto a wide range of substrates, including porous paper. In this work, the ink served as the conductive foundation of the entire sensor stack, enabling:
- Direct deposition onto paper without the need for vacuum processing, photolithography, or expensive cleanroom infrastructure
- A reproducible base electrode geometry that supports downstream functionalization
- A noble-metal printed surface chemically compatible with electrochemical gold nanoparticle deposition, allowing the team to mitigate the insulating gaps formed during sintering and significantly enhance electrical conductivity and surface uniformity
- Biocompatibility and electrochemical stability suitable for biosensing in phosphate-buffered saline at physiological pH
This combination of properties is what allows the GIPE/AuNPs/CH/MWCNTs composite electrode to exhibit a strong synergistic response: the AuNPs and MWCNTs together increase the electroactive surface area and accelerate electron transfer kinetics, while the chitosan matrix provides film stability and biocompatibility.
Analytical Performance
The fabricated sensor demonstrated outstanding analytical characteristics for isoniazid detection, including:
- A linear detection range of 1–100 µM
- Strong selectivity in the presence of common interferents
- Reproducible chronoamperometric response across multiple devices
- Stable operation on a flexible, low-cost paper substrate
These results position the device as a credible candidate for decentralized clinical monitoring of TB therapy, particularly in resource-constrained settings where instrumented laboratory analysis is impractical.
From Conductive Ink to Clinical Impact
This study reinforces a theme that runs through many of the applications NovaCentrix supports: when conductive materials are engineered for both print-process compatibility and downstream electrochemical performance, printed devices can move beyond proof-of-concept and into the regime of real diagnostic utility. Paper-based electrochemistry has been an active research area for more than a decade; what continues to unlock new device classes is the maturation of the underlying ink chemistries.
At NovaCentrix, we are proud to see Metalon® inks enabling work that contributes to global public health priorities, and we look forward to supporting the broader community as scalable printed biosensors move closer to clinical deployment.
➡️ Read the full paper: Torati, S. R.; Slaughter, G. “A Scalable Paper-Based Electrochemical Sensor Employing MWCNTs for Isoniazid Detection.” Advanced Sensor Research 5, no. 3 (2026): e70134. https://doi.org/10.1002/adsr.70134