Argentines develop a portable biosensor to detect hepatitis E in minutes

One of the most recent advances was published in December 2025 in the scientific journal ACS Sensors. The work presents a digital diagnostic kit for identify hepatitis Ean emerging viral infection in the country. The disease is usually transmitted by contaminated water and often goes unnoticed, since its symptoms are confused with other liver disorders.

The device, similar to a power bank, integrates a microfluidic cassette with graphene biochip (G-LOC), a portable reader (Zaphyrus) and a mobile app. When the nanoantibody detects the viral antigen, it generates an electrical variation that the sensor converts into a digital signaltransforming a molecular reaction into measurable data that indicates the presence of the virus.

“The graphene biochip with llama nanoantibodies detects the hepatitis E antigen in the sample. This interaction generates a unique bioelectronic signal. The Zaphyrus reader captures that response, converts it into digital data and sends it to the mobile app, where analysis models calculate the detected concentration,” explains Esteban Piccinini, CONICET researcher at INIFTA.

Nanoantibodies are derived from antibodies present in camelids such as llamas, alpacas or dromedaries. These molecules are ten times smaller than conventional antibodies from other mammals, allowing them to interact with great precision with viral proteins and access difficult-to-reach biological structures.

The focus on hepatitis E was not coincidental: it responds to the idea of ​​developing tools for underserved diseases but with a real impact on health. According to Omar Azzaroni, the joint work between different teams helped direct progress towards viruses that usually remain under the radar.

The need for new tools is linked to global expansion. The World Health Organization estimated that in recent years there were about 20 million cases of acute hepatitis E worldwide.

In this development, anoantibodies were made capable of recognizing the ORF2 antigen, considered the main marker of the virus. These molecules were generated at the Higher Institute for Biological Research (INSIBIO) and then integrated into the surface of the sensors used by the experimental device.

“Graphene chips allow direct and much simpler detection thanks to their atomic thickness and very high conductivity,” explains Piccinini. “On the other hand, traditional silicon sensors for diagnosing antigens require a ‘revealing’ step, which makes the equipment more complex, lengthens the measurement and explains why there are no commercial products based on this technology today.”

In addition, they added machine learning tools to refine the diagnosis. These systems, based on artificial intelligence, analyze large volumes of data and detect patterns that allow to improve performance and adjust the operation of the device as new information is incorporated.

“We started from sensitivity values ​​of 89% and specificity of 69%, and we managed to bring them to almost 100% after implementing the model. We trained it with thousands of measurements from graphene biochips, generating a predictive tool that improves over time: the more data it incorporates, the greater its capacity and diagnostic performance,” said Piccinini.

The platform works as a cooperation network between scientific institutions in the country. The Institute of Theoretical and Applied Physicochemical Research (INIFTA, CONICET-UNLP), the Institute of Physical Chemistry of Materials, Environment and Energy (INQUIMAE, CONICET-UBA) and the Higher Institute of Biological Research (INSIBIO, CONICET-UNT) participate.

“The main challenges when integrating the nanoantibody into the graphene chip were to preserve its biological activity, given its lability, and to avoid damaging the graphene, a sheet of atomic thickness. To achieve this, we designed and developed specific surface nanoengineering tools, today included in our intellectual property,” Piccinini explained.

The project is completed with the participation of the startup Gisens Biotech, a bioelectronics and nanotechnology company that emerged in La Plata and also has headquarters in the United States. The articulation between academic laboratories and technological ventures allowed us to accelerate the development of tools applicable to clinical diagnosis.

In this case, Gisens Biotech was in charge of designing an algorithm that analyzes the signals generated by the sensor and distinguishes more accurately between positive and negative samples. The incorporation of this digital analysis layer significantly increased the precision of the diagnostic system.

The advantage of this approach lies in its low cost. Adjusting the algorithm is much cheaper than redesigning the device hardware. In addition, the system could be adapted in the future to detect other viruses simply by modifying the analysis models.

Most infections resolve spontaneously within a period of two to six weeks. However, in some patients the disease evolves into chronic forms or fulminant hepatitis, conditions that present high mortality.

The virus circulates on different continents, although it is most prevalent in regions of Africa, Asia and parts of Central America. Argentina is considered a country of endemic steelbut during the last decade cases were recorded in central and northern provinces.

At the local level, the circulation of zoonotic variants of the virus was also identified. These strains can be transmitted from animals to humans, especially through consumption of undercooked pork or contact with rodents.

The diagnosis of hepatitis E is not fully standardized. Current tests require specific serological analyzes to detect antibodies against the virus, procedures that are usually performed in laboratories with specialized equipment.

Another important difference lies in the type of result that the system delivers. While many conventional tests only indicate whether the sample is positive or negativethe digital biosensor also provides a quantitative measurement of the viral antigen.

This data allows us to estimate the concentration of the virus present in the patient’s blood. This information is especially useful in persistent infections that require prolonged clinical follow-up.