As April ends, many countries are still quarantined due to the COVID-19 outbreak. Innovators in the paper industry have risen to the challenge, adapting rapid diagnostic tests to pinpoint the new viral disease. Projects continue, and we, at INNPAPER, have launched a competition to hear your ideas. Below is a run-down of these and other top stories from the printed electronics sector.

Paper-based diagnostic tests for COVID-19

Lateral flow assays are widely used in biomedicine for point-of-care applications, such as pregnancy tests. Using a paper substrate, these devices detect the presence of a target substance in a sample such as urine, mucus or blood. In the current outbreak, paper-assays are being adapted to detect antigens and antibodies for the new coronavirus, tell-tale signs of disease or an immune response.

While reverse-transcriptase polymerase chain reaction (RT-PCR) is the usual and most reliable method to diagnose COVID-19, these paper-based diagnostic tests have become the go-to alternative. They are cheap and, crucially, they offer results in minutes instead of hours. Here, MIT News details some of the efforts to adapt paper-based diagnostics during the current outbreak.

Coronavirus

A contest for printed electronics innovators

Printed batteries, displays, temperature, humidity and genetic sensors… Over the last two years, the European project INNPAPER has been developing these electronic items, using only paper and conductive inks. Now the technology is almost ready to be used, and we have launched an Open Call, looking for innovative ideas on how to use the project’s devices. Applications are open now, and the deadline is June 1st, 2020.

The winning proposal will get to kick-start the idea with the following rewards: a technical viability assessment, a manufacturing process flow, a roadmap to TRL 7 and an estimation of the cost of the technology. The winner will also gain privileged access to INNPAPER’s pilot printing line, which includes, among other technologies: cutting edge roll to roll pilot coating technology, surface characterisation including AFM and SEM, inks formulation and sheet to sheet printing techniques.

A DNA biosensor to detect adulterated food

Researchers in Greece have developed a paper-based DNA biosensor for food authenticity testing. The team, from the University of Patras, have tried their new device on dairy products, with the aim of discerning milk yogurts which contain mixtures from different species: cow, ewe and goat. The biosensor uses gold nanoparticles for visual detection and, according to the researchers, could be used to signal adulteration in other food products, including meat, oil and legumes.

Safety stickers warn of spoiled food

Some foods only keep well if they are frozen or refrigerated. Exposing them to room temperature encourages the growth of pathogens which can cause food poisoning. But sometimes it’s difficult to discern whether food has gone bad, because certain bacteria don’t alter the taste or smell of the product. A smart label developed at Korea Research Institute of Chemical Technology generates visual cues when food packaging is exposed to room temperature. Read about it in Printed Electronics World.