From thin patches attached to the skin to technologies where breathing bacteria generate electricity, discover future technologies that will more intelligently protect our health and environment.
Biosensors are next-generation sensing devices that combine the sophisticated detection capabilities of living organisms with electronic technology. Starting with the small devices used by diabetes patients to measure blood sugar, this technology has now evolved into wearable devices that detect environmental pollution, diagnose cancer at early stages, and track our health status in real time. The global biosensor market, which was worth approximately $30.1 billion in 2023, is predicted to grow at an average annual rate of 7.7% until 2032, with its importance and potential increasing daily1 .
Biosensors are analytical devices that combine biological elements with physicochemical detectors3 . They can be likened to the sharp senses of a "biological nose" combined with a "transducer" that converts these senses into electrical signals.
The biosensor detects specific substances through biological recognition and converts this interaction into measurable signals.
Biosensors are primarily classified according to their biological recognition elements:
Blood glucose meters using glucose oxidase are the most representative example. When the enzyme reacts with glucose, current is generated, and this signal is measured to determine blood glucose concentration3 .
Used to find specific gene sequences. Utilized in genetic disease diagnosis and virus detection3 .
Uses living cells or microorganisms to detect environmental changes or toxic substances. Also applied to assess water quality by measuring current generated during bacterial respiration5 .
Biosensors are rapidly developing to become more accurate, smaller, and more convenient.
Recently, sensors that attach directly to the skin and monitor various biometric indicators in sweat in real-time are gaining attention. A research team from Sungkyunkwan University developed an optical biosensor adhesive patch inspired by the structure of frog soles8 . This patch quickly absorbs trace amounts of sweat (75nL) within 45 seconds, enabling simultaneous detection of vitamin concentration or stress indicators8 .
A joint research team from DGIST and Seoul National University developed technology to mass-produce high-performance biosensors by spraying carbon nanotube ink like an inkjet printer7 . This 'drop-and-spread' method, which uses the surface tension of liquid droplets to make nanotubes self-align, is attracting attention as an innovation that could replace complex and expensive processes7 .
In the biosensor market, the electrochemical method is the most widely used technology, accounting for 41.6% of the total as of 20231 . In particular, field-effect transistor (FET)-based sensors can detect extremely small amounts of substances, detecting the neurotransmitter serotonin at concentrations as low as 42 picomolar (pM), less than the cross-sectional area of a hair, showing potential for early diagnosis of neurological disorders such as depression and Parkinson's disease7 .
Technological advancements have also significantly improved sensor lifespan and convenience. Sensors like Dexcom's 'Stelo Glucose Biosensor', which can be attached once and provide continuous data for 15 days, are emerging, reducing user burden1 .
Days of continuous use
Real-time monitoring
Calibration needed
Recently, a Norwegian research team developed a microbial biosensor that measures Biochemical Oxygen Demand (BOD) in real time using the principle of microbial fuel cells5 . BOD is an important indicator of water pollution levels, and this experiment well demonstrates the appeal of biosensors that cross the boundaries between living organisms and engineering.
The research team confirmed a clear proportional relationship between glucose concentration and generated current intensity. This means that BOD can be accurately estimated from current values alone5 .
| Glucose Concentration (mg/L) | Relative Current Output |
|---|---|
| 50 |
|
| 150 |
|
| 300 |
|
| External Resistance Setting | Detection Range | Applicable Scenarios |
|---|---|---|
| Low | Wide (High Concentration) | High-concentration wastewater monitoring |
| High | Narrow (Low Concentration) | Trace pollution surveillance in water sources |
This experiment demonstrated that microbial biosensors can be powerful tools for real-time BOD monitoring in wastewater treatment plants or rivers. Analysis that previously took several days can now be performed in near real-time, potentially revolutionizing the efficiency of water quality management5 .
The performance of biosensors is greatly influenced by the materials that compose them. Below are the essential materials and their roles in the latest biosensor development.
Electrode, flexible circuit pattern printing
Graphene ink (flexibility), silver nanoparticle ink (high conductivity), etc.4
High-sensitivity transistor-type biosensor configuration
Detects analytes through conductivity changes upon surface binding6
Electrochemical biosensors dominate the market
The future of biosensors leads to core technologies for more precise and personalized healthcare and sustainable living coexisting with the environment.
Bioinks combined with 3D bioprinting technology will create 'organ chips' that mimic patient-specific tissues, to be used in new drug development or verification of customized treatment methods4 . This could become a more accurate and ethical method replacing animal testing.
As inkjet printing technology developed by DGIST becomes mainstream, biosensors will evolve into low-cost sticker forms that can be attached anywhere7 . These sensors will connect to smartphones, building networks that constantly monitor our health and surrounding environment.
Microbial fuel cell sensors, where bacteria generate electricity, will perform long-term monitoring of water and air pollution in remote areas where power supply is difficult, operating on self-power5 .
Biosensors are no longer future technology. They are reality worn on our wrists, attached to our skin, and already operating in rivers and factories. We are unraveling the sophisticated detection capabilities that life has refined through long evolution with human technology, using them as tools to create a healthier and safer world. The infinite possibilities of how these small devices that read life's signals will change our tomorrow continue to unfold.
This article provides an easy explanation of the basic principles and latest trends in biosensors. For more in-depth technical information, please refer to the original texts in the references.