Tag Archives: Jean-François Masson

An artificial tongue, gold, and maple syrup

I have always imagined the love of maple syrup to be a universal love. A friend who moved to Canada from somewhere else in the world disillusioned me on that subject. She claims to be unable to grasp why anyone would love maple syrup. Should you recognize yourself in those words you may not find this post all that interesting.

However, maple syrup lovers may find this May 5, 2020 news item on Nanowerk a bit disconcerting,

It’s said that maple syrup is Quebec’s liquid gold. Now scientists at Université de Montréal have found a way to use real gold — in the form of nanoparticles — to quickly find out how the syrup tastes.

The new method — a kind of artificial tongue — is validated in a study published in Analytical Methods (“High-throughput plasmonic tongue using an aggregation assay and nonspecific interactions: classification of taste profiles in maple syrup”), the journal of the Royal Society of Chemistry, in the United Kingdom.

The “tongue” is a colorimetric test that detects changes in colour to show how a sample of maple syrup tastes. The result is visible to the naked eye in a matter of seconds and is useful to producers.

“The artificial tongue is simpler than a human tongue: it can’t distinguish the complex flavour profiles that we can detect,” said UdeM chemistry professor Jean-François Masson, who led the study. “Our device works specifically to detect flavour differences in maple syrup as it’s being produced.”

A chemistry professor at Université de Montréal has developed a new test using gold nanoparticles to establish the flavour profile of maple syrup and help producers evaluate its quality. Courtesy: Université de Montréal

There is more information but the central question as to why anyone would want an artificial tongue for tasting maple syrup is never answered (presumably they want to speed up production and ensure more consistent classification) nor is there much in the way of technical detail in a May 5, 2019 Université de Montréal news release (also on EurekAlert),

1,818 samples tested

The artificial tongue was validated by analyzing 1,818 samples of maple syrup from different regions of Quebec. The syrups that were analyzed represented the various known aromatic profiles and colours of syrup, from golden to dark brown.

“We designed the ‘tongue’ at the request of the Québec Maple Syrup Producers to detect the presence of different flavour profiles,” explained Simon Forest, the study’s first author. “The tool takes into account the product’s olfactory and taste properties.”

Maple syrup has a molecular complexity similar to that of wine. Its taste is delicate, without bitterness, and it has a subtle aroma. During the production process, specialized human tasters are employed to judge which profile each batch fits into.

“The development of the artificial tongue is intended to support the colossal work that is being done in the field to do the first sorting of syrups quickly and classify them according to their qualities,” said Masson.

Red for the best, blue for the rest

The researchers compare the artificial tongue to a pH test for a swimming pool. You simply pour a few drops of syrup into the gold nanoparticle reagent and wait about 10 seconds.

If the result stays in the red spectrum, it has the characteristics of a premium quality syrup, the kind best loved by consumers and sold in grocery stores or exported.

If, on the other hand, the test turns blue, the syrup may have a flavour “defect”, which may be treated as an industrial syrup for use in processing.

“It doesn’t mean the syrup is not good for consumption or that it has a different sugar level,” Masson said of the “blue” type syrup, which the food industry uses as a natural sweetener in other products. “It just may not have the usual desired characteristics, and so can’t be sold directly in bottles to consumers.”

60 categories of taste

Caramelized, woody, green, smoked, salty, burnt — the taste of maple syrup has as many as 60 categories to fit into. Maple syrup is essentially a concentrated sugar solution of 66 per cent sucrose and 33 per cent water; the remaining one per cent of other compounds determines the taste.

Like wine, the taste of maple syrup changes according to a variety of factors, including the harvest period, the region, production and storage methods and, of course, the weather. Too much variation in temperature over a weekend, for instance, can greatly affect the taste profile of the product.

The artificial tongue developed at UdeM could someday be adapted for tasting wine or fruit juice, Masson said, as well as be useful in a number of other agrifood contexts.

Here’s a link to and a citation for the paper,

A high-throughput plasmonic tongue using an aggregation assay and nonspecific interactions: classification of taste profiles in maple syrup by Simon Forest, Trevor Théorêt, Julien Coutu, and Jean-Francois Masson. Anal. Methods, 2020, Advance Article DOI: https://doi.org/10.1039/C9AY01942A First published 05 May 2020

This paper is behind a paywall.

Faster, cheaper, and just as good—nanoscale device for measuring cancer drug methotrexate

Lots of cancer drugs can be toxic if the dosage is too high for individual metabolisms, which can vary greatly in their ability to break drugs down. The University of Montréal (Université de Montréal) has announced a device that could help greatly in making the technology to determine toxicity in the bloodstream faster and cheaper according to an Oct. 27, 2014 news item on Nanowerk,

In less than a minute, a miniature device developed at the University of Montreal can measure a patient’s blood for methotrexate, a commonly used but potentially toxic cancer drug. Just as accurate and ten times less expensive than equipment currently used in hospitals, this nanoscale device has an optical system that can rapidly gauge the optimal dose of methotrexate a patient needs, while minimizing the drug’s adverse effects. The research was led by Jean-François Masson and Joelle Pelletier of the university’s Department of Chemistry.

An Oct. 27, 2014 University of Montréal news release, which originated the news item, provides more specifics about the cancer drug being monitored and the research that led to the new device,

Methotrexate has been used for many years to treat certain cancers, among other diseases, because of its ability to block the enzyme dihydrofolate reductase (DHFR). This enzyme is active in the synthesis of DNA precursors and thus promotes the proliferation of cancer cells. “While effective, methotrexate is also highly toxic and can damage the healthy cells of patients, hence the importance of closely monitoring the drug’s concentration in the serum of treated individuals to adjust the dosage,” Masson explained.

Until now, monitoring has been done in hospitals with a device using fluorescent bioassays to measure light polarization produced by a drug sample. “The operation of the current device is based on a cumbersome, expensive platform that requires experienced personnel because of the many samples that need to be manipulated,” Masson said.

Six years ago, Joelle Pelletier, a specialist of the DHFR enzyme, and Jean-François Masson, an expert in biomedical instrument design, investigated how to simplify the measurement of methotrexate concentration in patients.

Gold nanoparticles on the surface of the receptacle change the colour of the light detected by the instrument. The detected colour reflects the exact concentration of the drug in the blood sample. In the course of their research, they developed and manufactured a miniaturized device that works by surface plasmon resonance. Roughly, it measures the concentration of serum (or blood) methotrexate through gold nanoparticles on the surface of a receptacle. In “competing” with methotrexate to block the enzyme, the gold nanoparticles change the colour of the light detected by the instrument. And the colour of the light detected reflects the exact concentration of the drug in the blood sample.

The accuracy of the measurements taken by the new device were compared with those produced by equipment used at the Maisonneuve-Rosemont Hospital in Montreal. “Testing was conclusive: not only were the measurements as accurate, but our device took less than 60 seconds to produce results, compared to 30 minutes for current devices,” Masson said. Moreover, the comparative tests were performed by laboratory technicians who were not experienced with surface plasmon resonance and did not encounter major difficulties in operating the new equipment or obtaining the same conclusive results as Masson and his research team.

In addition to producing results in real time, the device designed by Masson is small and portable and requires little manipulation of samples. “In the near future, we can foresee the device in doctors’ offices or even at the bedside, where patients would receive individualized and optimal doses while minimizing the risk of complications,” Masson said. Another benefit, and a considerable one: “While traditional equipment requires an investment of around $100,000, the new mobile device would likely cost ten times less, around $10,000.”

For those who prefer to read the material in French here’s a link to ‘le 27 Octobre 2014 communiqué de nouvelles‘.

Here’s a prototype of the device,

Les nanoparticules d’or situées à la surface de la languette réceptrice modifient la couleur de la lumière détectée par l’instrument. La couleur captée reflète la concentration exacte du médicament contenu dans l’échantillon sanguin. Courtesy  Université de Montréal

Les nanoparticules d’or situées à la surface de la languette réceptrice modifient la couleur de la lumière détectée par l’instrument. La couleur captée reflète la concentration exacte du médicament contenu dans l’échantillon sanguin. Courtesy Université de Montréal

There is no indication as to when this might come to market, in English  or in French.