Office printer can spot infectious diseases

Researchers from the McMaster University have developed a new way to print paper biosensors, simplifying the diagnosis of many bacterial and respiratory infections.

Using state-of-the-art methods to produce "bio-inks", researchers can use conventional office ink-jet printers to print man-made DNA molecules with very high molecular weight on paper, much like printing a letter in an office.

The sheer size of the DNA - which produces a signal when a specific disease biomarker is present - is enough to ensure it remains immobilised and, therefore, stable.

The paper sensor emerges from the printer ready to use like pH paper.

The new platform is the latest in a progression of paper-based screening technologies.

These enable users to generate a clear, simple answer in the form of letters and symbols that appear on the test paper to indicate the presence of infection or contamination in people, food or the environment.

"The simplicity of use makes the system easy and cheap to implement in the field or in the doctor's office," said John Brennan, director of McMaster's Biointerfaces Institute.

Imagine being able to clearly identify contaminated meat, vegetables or fruit.

"For patients suspected of having infectious diseases like C. diff (Clostridium difficile colitis), this technology allows doctors to quickly and simply diagnose their illnesses, saving time and expediting what could be life-saving treatments," Brennan said in a university statement.

This method can be extended to virtually any compound -- be it a small molecule, bacterial cell or virus.

The research, in its formative stage, addresses a key problem facing current paper-based biosensing techniques which are labour-intensive, sometimes costly and inconvenient, and often difficult to mass produce.

The implications are significant, says Brennan, since the new technology could be used in many fields where quick answers to important questions are critical.

"We could conceivably adapt this for numerous applications which would include rapid detection of cancer or monitoring toxins in the water supply," Brennan said.