The question sounded straightforward: can our company print a biosensor? On paper, everything looked obvious – layers of conductive silver, a dielectric, and a graphite electrode. A classic sequence familiar to every printed electronics specialist. Only the first trials revealed the truth: between theory and practice lies a gap full of technological surprises.

A series of tests instead of a quick solution

Our biosensor worked, but its parameters were unpredictable. Each subsequent production run delivered different results. The problem was not limited to a single element – it turned out that every detail of the process affected the final outcome in ways that could not be anticipated at the planning stage.

Analyzing the causes of instability required systematic testing of dozens of parameter combinations. Our team began methodically checking every piece of the puzzle: from the composition of graphite and dielectric pastes, through screen mesh density, to the drying conditions of individual layers.

It turned out that seemingly marginal differences – a few micrometers in emulsion thickness or a few degrees Celsius during drying – radically changed the sensor’s properties. Every modification required verification of the entire process from scratch. After weeks of testing, we finally defined a precise set of parameters that guaranteed repeatable results.

Specialized pastes instead of standard inks

Standard materials used in industrial printing proved completely insufficient. Ordinary conductive inks do not provide the conductivity stability required in biomedical applications. Chemical resistance was an even greater challenge – contact with biological fluids quickly exposed the weaknesses of common formulations.

It became necessary to use specialized pastes developed specifically for electronics and medical applications. Each layer required individual material selection: silver pastes had to ensure low resistance, graphite pastes had to provide appropriate electrochemical reactivity, and dielectric pastes had to deliver perfect insulation.

We tested products from various manufacturers, analyzing rheological properties, drying times, and curing temperatures. Only precise correlation of paste properties with printing process parameters allowed us to obtain biosensors with stable, repeatable characteristics.

Screen printing technology in biosensor production

In an era dominated by digital technologies, it may seem surprising that classical screen printing proved to be the optimal solution for biosensor production. Yet this traditional method, based on coating the screen with photosensitive emulsion, provides a level of parameter control unavailable in digital printing.

Precise control of layer thickness is fundamental in printed electronics manufacturing. A difference of just a few microns changes the electrical characteristics of the entire system. Screen printing enables this repeatability thanks to precise selection of mesh density and controlled emulsion thickness.

The geometry of deposited layers, their uniformity, and their mutual interaction determine sensor functionality. Digital technologies, although faster and more flexible, do not offer the same level of control over these critical parameters.

What determined the success of the project?

Several companies from the printed electronics sector were involved in the project. All had access to similar materials and technologies. Yet it was our team that managed to develop a fully functional biosensor meeting the defined requirements.

The difference lay in consistency of the R&D approach and in-depth understanding of the behavior of conductive materials under varying conditions. Our experience in screen printing, combined with systematic testing and result analysis, proved decisive.

The developed solutions became the foundation for subsequent projects in printed electronics. This story confirms that in advanced technologies, the foundation remains practical technical knowledge, patience, and precision at every stage of the process.

Biosensor manufacturing requires more than theoretical knowledge and access to appropriate equipment. Success depends on the ability to combine expertise from materials science, chemistry, and process engineering – and to translate that knowledge into stable, repeatable production procedures.