Toxin detection as close as an inkjet printer

Jul 13, 2009
This is topography of inkjet-sprayed PVAm, and AChE (50 U/mL) and DTNB doped sodium silicate (SS) thin films on paper. Credit: McMaster University

If that office inkjet printer has become just another fixture, it's time to take a fresh look at it. Similar technology may soon be used to develop paper-based biosensors that can detect certain harmful toxins that can cause food poisoning or be used as bioterrorism agents.

In a published in the July issue of , John Brennan and his research team at McMaster University, working with the Sentinel Bioactive Paper Network, describe a method for printing a toxin-detecting on paper using a FujiFilm Dimatix Materials Printer.

The researchers demonstrated the concept on the detection of acetylcholinesterase (AChE) inhibitors such as paraoxon and aflatoxin B1 on paper using a "lateral flow" sensing approach similar to that used in a home pregnancy test strip.

The process involves formulating an ink like the one found in computer printer cartridges but with special additives to make the ink biocompatible. An ink comprised of biocompatible silica is first deposited on paper, followed by a second ink containing the enzyme, and the resulting bio-ink forms a thin film of enzyme that is entrapped in the silica on paper. When the enzyme is exposed to a toxin, reporter molecules in the ink change colour in a manner that is dependent on the concentration of the toxin in the sample.

This simple and cost-effective method of adhering biochemical reagents to paper is expected to bring the concept of bioactive paper a significant step closer to commercialization. The goal for bioactive paper is to provide a rapid, portable, disposable and inexpensive way of detecting harmful substances, including toxins, pathogens and viruses, without the need for sophisticated instrumentation. The research showed that the printed enzyme retains full activity for at least two months when stored properly, suggesting that such sensor strips should have a good shelf life.

Portable bio-sensing papers are expected to be extremely useful in monitoring environmental and food-based toxins, as well as in remote settings in less industrialized countries where simple bioassays are essential for the first stages of detecting disease.

Applications for bioactive paper also include clinical applications in neuroscience, drug assessment, and pharmaceutical development.

Source: McMaster University (news : web)

Explore further: Detecting infection with a microchip

add to favorites email to friend print save as pdf

Related Stories

Printers to produce life-saving organs

Dec 12, 2005

A team of American scientists is studying the potential of printers being developed to produce life-saving organs, reports Wired.com. They believe that any organ, a skin graft, a new trachea or a heart patch ...

World's First 10.1" Flexible Electronic Paper Display

Oct 21, 2005

LG.Philips LCD and E Ink have built a 10.1" flexible electronic paper display. Less than 300 microns thick, the paper-white display is as thin and flexible as construction paper. With a 10.1" diagonal, the prototype achieves ...

A Printer that Delivers 1,000 Pages a Minute?

Sep 21, 2006

Two researchers from The College of Judea and Samaria in Israel have designed an ink-jet printer head that could lead to printers capable of chugging out 1,000 pages per minute – or even more.

Recommended for you

Research offers 'promise' of improved food safety

22 hours ago

The issue of food safety has rocketed up the political agenda in recent years but despite huge improvements, some concerns and problems still persist. Fears about our food are moving away from issues about ...

Metals go from strength to strength

22 hours ago

To the human hand, metal feels hard, but at the nanoscale it is surprisingly malleable. Push a lump of metal with brute force through a right-angle mould or die, and while it might look much the same to the ...

Chemists achieve molecular first

22 hours ago

(Phys.org) —Chemists from Trinity College Dublin have achieved a long-pursued molecular first by interlocking three molecules through a single point. Developing interlocked molecules is one of the greatest ...

User comments : 0

More news stories

Chemists achieve molecular first

(Phys.org) —Chemists from Trinity College Dublin have achieved a long-pursued molecular first by interlocking three molecules through a single point. Developing interlocked molecules is one of the greatest ...

Metals go from strength to strength

To the human hand, metal feels hard, but at the nanoscale it is surprisingly malleable. Push a lump of metal with brute force through a right-angle mould or die, and while it might look much the same to the ...

First direct observations of excitons in motion achieved

A quasiparticle called an exciton—responsible for the transfer of energy within devices such as solar cells, LEDs, and semiconductor circuits—has been understood theoretically for decades. But exciton movement within ...

Warm US West, cold East: A 4,000-year pattern

Last winter's curvy jet stream pattern brought mild temperatures to western North America and harsh cold to the East. A University of Utah-led study shows that pattern became more pronounced 4,000 years ago, ...

Patent talk: Google sharpens contact lens vision

(Phys.org) —A report from Patent Bolt brings us one step closer to what Google may have in mind in developing smart contact lenses. According to the discussion Google is interested in the concept of contact ...

Tech giants look to skies to spread Internet

The shortest path to the Internet for some remote corners of the world may be through the skies. That is the message from US tech giants seeking to spread the online gospel to hard-to-reach regions.