The inquiry sounded straightforward: could our company print a biosensor? On paper, everything seemed obvious—layers of conductive silver, dielectric, graphite electrode. A classic sequence known to every specialist in printed electronics. Only the first attempts 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 production batch delivered different results. The problem wasn’t limited to a single component—every detail of the process affected the final outcome in ways impossible to foresee at the planning stage.

Analyzing the causes of instability required systematic testing of dozens of combinations. Our team began methodically examining each element of the puzzle: from the composition of graphite and dielectric pastes, through the mesh density used in screen printing, 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 properties of the sensor. Every modification required verifying the entire process from the beginning. After weeks of testing, we finally determined a precise set of parameters that guaranteed repeatable results.

Specialized pastes instead of standard inks

Standard materials used in industrial printing proved completely insufficient. Regular conductive inks do not provide the conductivity stability required in biomedical applications. Even more challenging was chemical resistance—contact with biological fluids quickly revealed the weaknesses of popular formulations.

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

We tested products from various manufacturers, analyzing rheological parameters, drying time, and curing temperature. Only by precisely correlating paste properties with printing process parameters were we able to produce biosensors with stable, repeatable characteristics.

Screen printing technology in biosensor production

In an era dominated by digital technologies, it may seem surprising that classic screen printing turned out to be the optimal solution for biosensor production. Yet this traditional method, involving coating a screen with photosensitive emulsion, enables parameter control unattainable for digital printers.

Precise management of layer thickness is fundamental in printed electronics. A difference of a few microns changes the electrical characteristics of the entire system. Screen printing allows achieving this repeatability thanks to the ability to select mesh density and control emulsion thickness.

The geometry of applied layers, their uniformity, and mutual interaction determine the functionality of the sensor. Digital technology, although faster and more flexible, cannot offer such control over these parameters.

What determined the success of the project?

Several companies from the printed electronics industry were involved in the project. All had access to similar materials and technologies. Yet it was our team that managed to create a fully functional biosensor that met the required specifications.

The difference was consistency in the research-and-development approach and deep knowledge of the behavior of conductive materials in various conditions. Our experience in screen printing, combined with systematic testing and result analysis, proved decisive.

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

Producing biosensors requires more than theoretical knowledge and access to the right equipment. Success depends on the ability to combine expertise from various fields—materials science, chemistry, process engineering—and convert that knowledge into stable, repeatable production procedures.