A New Era of Glucose Biosensors 🩸 Nano Gold & Platinum

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Discover how Pt/Au nanostructures are transforming abiotic glucose biosensors—bringing more stability, affordability, and precision to diabetes monitoring.

Published September 9, 2025 By EngiSphere Research Editors
Glucose Biosensors Made of Nano Gold & Platinum © AI Illustration
Glucose Biosensors Made of Nano Gold & Platinum © AI Illustration

TL;DR

Researchers developed a stable, enzyme-free glucose biosensor using platinum–gold nanostructures on PCBs, achieving high sensitivity, long shelf-life, and real-world applicability for future wearable diabetes monitoring.

The R&D

Why Glucose Monitoring Matters 🩺💡

Diabetes is a major public health issue of our era. Over 463 million people worldwide lived with it in 2019, and projections suggest 700 million by 2045. Managing this condition largely depends on one thing: monitoring blood glucose levels.

If blood sugar runs too high or too low, complications can arise—ranging from nerve and eye damage to heart and kidney problems. That’s why glucose sensors are lifesaving tools, empowering patients to check and control their sugar levels daily.

Traditional glucose biosensors rely on enzymes, especially glucose oxidase, to detect glucose with great accuracy. But enzymes are fragile—they degrade under heat, pH changes, and humidity. They’re also costly and have limited shelf life.

This is where abiotic (enzyme-free) glucose sensors step in. The research we’re covering today introduces a robust, innovative design using gold (Au) and platinum (Pt) nanostructures—promising a cheaper, more stable, and more durable way to measure glucose.

The Core Innovation: Pt/Au Composite Nanostructures 🧪🔬

The study from the University of Bath reports a composite nanostructured electrode built on a printed circuit board (PCB). The design layers materials with complementary strengths:

1. Highly porous gold (hPG)
  • Gold was electrodeposited into a sponge-like 3D structure.
  • This porous structure massively increases the surface area, creating countless active sites for glucose reactions.
2. Polyaniline (PANI)
  • A conductive polymer added on top of the gold.
  • Acts as a protective layer, boosting durability and preventing gold from breaking down.
3. Platinum nanoparticles (PtNPs)
  • Embedded directly into the PANI during synthesis.
  • Provide superior catalytic activity, speeding up glucose oxidation while staying firmly attached thanks to the PANI “glue.”

👉 The result: a PANI-Pt/hPG/Au electrode, combining the best of all worlds—high activity, excellent conductivity, and long-term stability.

How Does It Work? ⚡

Instead of relying on enzymes to break down glucose, these electrodes catalyze direct electrochemical oxidation of glucose molecules at their surfaces.

  • When glucose is present, it interacts with the gold and platinum catalytic sites.
  • This generates an electrical signal (a measurable current).
  • The stronger the current, the higher the glucose concentration.

This method is faster, more stable, and enzyme-free—making it perfect for future wearable or implantable glucose monitors.

Performance Results 🎯📊

The research team tested three electrode versions:

  • hPG/Au (gold only)
  • PANI/hPG/Au (gold + PANI)
  • PANI-Pt/hPG/Au (gold + PANI + platinum)
Sensitivity to Glucose
  • PANI-Pt/hPG/Au: 95.12 µA mM⁻¹ cm⁻² in buffer solution 🥇
  • hPG/Au: 50.63 µA mM⁻¹ cm⁻²
  • PANI/hPG/Au: 38.93 µA mM⁻¹ cm⁻²

👉 The platinum-enhanced electrode was almost twice as sensitive as porous gold alone!

Detection Limit
  • Could detect glucose at just 0.047 mM, far below normal blood levels (3.9–7.8 mM).
  • This means it’s clinically relevant and highly accurate.
Realistic Testing

They also tested electrodes in synthetic interstitial fluid (SIF)—a liquid mimicking the fluid between human cells.

  • Sensitivity dropped to 28.23 µA mM⁻¹ cm⁻² due to ion interference (like chloride ions competing with glucose).
  • But this is still excellent compared to other non-enzymatic sensors, proving it works under real-world conditions.
Stability Over Time ⏳

One of the most impressive results: long-term stability.

  • PANI-Pt/hPG/Au retained over 90% activity after 90 days in SIF.
  • By contrast, bare porous gold electrodes lost over 85% of their activity in the same time.

Thanks to the PANI layer, the platinum nanoparticles stayed firmly attached and dispersed—preventing agglomeration or leaching.

This is huge news for practical devices: it means a sensor could stay reliable for months without replacement.

Why This Matters 🌍

The development ticks several critical boxes for next-gen glucose biosensors:

Enzyme-free: no fragility or high costs of biological materials.
Scalable & cheap: one-step synthesis and PCB integration make mass production feasible.
Durable: strong performance even in complex fluids over months.
Wearable-ready: can be built into compact, low-cost, non-invasive devices.

This could transform how millions of people monitor diabetes—making continuous glucose monitoring more affordable, robust, and accessible worldwide.

Future Prospects 🔭

The authors see several exciting directions:

  1. Integration into Wearables 👕⌚
    The PCB-based design makes it perfect for smart patches, wristbands, or microneedle arrays that continuously track glucose painlessly.
  2. Fuel Cell Applications ⚡🔋
    These electrodes could also double as biofuel cell anodes, powering small medical devices by harvesting energy from glucose in the body.
  3. Biocompatibility Studies 🧬
    More tests are needed to confirm how these nanostructures behave long-term inside the body, ensuring safety.
  4. Multi-Analyte Sensors 🔍
    With modifications, the same platform could measure lactate, cholesterol, or other biomarkers—creating all-in-one health monitors.
Wrapping Up 🌟

This research shows that gold and platinum nanostructures, supported by conductive polymers, can deliver a new generation of glucose biosensors.

The PANI-Pt/hPG/Au electrode:

  • Doubled sensitivity compared to porous gold,
  • Worked in realistic body-like fluids, and
  • Stayed stable for three months without significant degradation.

It’s a big step towards reliable, affordable, enzyme-free glucose monitoring—a game-changer for diabetes care and beyond. 🌍💙


Terms to Know

Biosensor 🧪 A device that detects a specific chemical (like glucose) and converts it into a measurable signal (like an electrical current). Think of it as a tiny detective that spots molecules. - More about this concept in the article "Revolutionizing Antioxidant Detection: Bacteria-Powered Biosensors for a Healthier Tomorrow 🌱".

Glucose 🍬 A type of sugar that serves as the primary energy source for our body's cells. Monitoring glucose levels is crucial for people with diabetes to stay healthy.

Enzyme-based Sensor ⚡ Traditional biosensors that use biological catalysts (enzymes) like glucose oxidase to detect glucose. They’re very accurate but fragile and expensive.

Abiotic (Enzyme-free) Sensor ⚙️ A sensor that doesn’t rely on enzymes. Instead, it uses metals or polymers to directly detect glucose—making it cheaper and more stable.

Nanostructures 🔬 Materials engineered at the nanoscale (a billionth of a meter). At this tiny size, metals like gold and platinum have special properties that boost sensor performance. - More about this concept in the article "Harnessing the Power of Light: How Black Silicon Revolutionizes Solar Cell Efficiency 🌞 ⬛".

Highly Porous Gold (hPG) ✨ Gold structured like a sponge with many tiny holes. This massively increases its surface area, giving glucose more spots to “dock” and react.

Platinum Nanoparticles (PtNPs) ⚡ Extremely small particles of platinum that act as powerful catalysts, speeding up glucose reactions and producing stronger signals.

Polyaniline (PANI) 🧩 A conductive polymer (plastic-like material) that improves stability and keeps nanoparticles from clumping or falling off the electrode.

Printed Circuit Board (PCB) 💻 The same green boards you see in electronics. Here, they’re used as a cheap, scalable base for building glucose sensors.

Interstitial Fluid (SIF) 💧 The liquid that surrounds our body’s cells. Sensors that can read glucose here enable non-invasive monitoring (no finger-pricking!).


Source: Niyazi, A.; Linden, A.; Di Lorenzo, M. Robust Pt/Au Composite Nanostructures for Abiotic Glucose Sensing. Biosensors 2025, 15, 588. https://doi.org/10.3390/bios15090588

From: University of Bath.

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