Infrared sensing technology developments – summarised

In our regular series we break down our favourite news and research from academic and trade journals- a collection of what you need to know and what has simply caught our eye.

1) Walmart sued for mis-selling homeopathic medicines

We open this month with news from the US where the country’s largest retailer, Walmart, is being sued by the District of Columbia, the Center for Inquiry (CFI) for medical fraud for the alleged mis-selling of homeopathic remedies alongside real medicines, positioning them in the same sections and under the same signs. Additionally, the company’s website brings up homeopathic medicine when people search for, for example, cold and flu or children’s remedies.

We thought we’d use this excuse to share some of our favourite papers on this subject, in which mid-IR spectroscopy is used to disprove the arguments made by homeopaths.

For those who don’t follow homeopathy (or the various debunking of it – see here Dr Ben Goldacre’s wonderful articles on the subject), solutions are prepared by running a series of dilution – so 1ml of a substance dissolved into 100ml of water or ethanol and repeating. The homeopathic flu remedy Oscillococcinum, for example, has a 200C scale (i.e. 200 repetitions) – so to contain one molecule of the original substance, a person would need to consume a mass 10320 times that of the observable universe.

People using a homeopathic remedy to treat a cold is one thing. However, others are turning to it to treat cancer and other life-threatening diseases. But some studies show that those using it to treat cancer are twice as likely to die as someone using a conventional treatment.

Homeopaths say the water contains a “memory” of the substance. We love how, instead of simply using maths to show this, a 2004/5 paper by Dr David Anick MD of the Harvard Medical School and Sukul et al, used a combination of infrared and NMR spectroscopy to examine samples and give evidence of there being not only no molecules of an active substance, but no change in the way water molecules interacted due to the “memory.”

As David Anick put it, there were “no discrete signals suggesting a difference between remedies and controls,” and the results were not supporting the hypothesis “that remedies made in water contain long-lived non-dynamic alterations of the H-bonding pattern of the solvent.”

2) In vivo analysis of human muscles and tissue oxygenation

For those that have undergone surgery, whether for a knee/hip replacement or something more routine, the recovery process is vital. But it’s also very hard to measure success, with surgeons routinely taking data from surveys (which people lie on in order to avoid further surgery) or interviews (which capture a once-a-month snapshot only). More recently they’ve begun using IoT systems to track daily movement and activity to tailor recovery programmes. This allows them to try and slow down people trying to do too much and understand why some don’t do enough.

We read with particular interest one paper published in June on the ability of infrared spectroscopy to be used to categorise and analyse human tissues, with each giving unique signatures. As the researchers state: infrared spectroscopy “proved valuable for non-invasive assessment of tissue optical properties in vivo… providing the spectral signatures (i.e. “fingerprints”) of upper limb flexors and extensors, which represent specific, accurate, and reproducible measures of the overall biological status of these muscles.”

The researchers also highlighted that the non-invasive spectroscopy technique enabled “more thorough evaluation of the muscular system and optimal monitoring of the effectiveness of therapeutic or rehabilitative interventions.”

The full paper is available here:

3) $100m of fake food and drink seized with 672 million arrested

We’ve written before about fake food scandals – ranging from the exploitation of complex supply chains to use cheap ingredients that can result in culturally insensitive (but safe) errors to the outright dangerous practices such as putting antifreeze into wine or melamine into baby milk.

Absorbance spectral features of minced beef meat adulterated with horsemeat. The arrow indicates the direction of increasing the level of adulteration. The most significant absorption wavelengths are highlighted – reproduced with permission from Kamruzzaman et al., 2015

Last month saw yet another food scandal, with a Europol/Interpol collaboration leading to 672 people being arrested and over $100 million of fake food and drinks being seized across 78 countries, to remove 16,000 tonnes and 33 million litres of potentially dangerous fake food and drink from global supply chains. This ranged from 4,200 litres of illicitly produced vodka by Russian officers to 150,000 litres of sunflower oil coloured with chlorophyll / beta-carotene to pass off as more-expensive olive oil. The scale of the problem facing officers is summed up in the size of the operation, with 67,000 inspections taking place at shops, markets, airports, seaports and industrial estates over a period of just 4 months.

A quick, portable, easy to use and reliable system is therefore needed to enable affordable testing of hundreds of thousands of samples in situ. Mid-IR spectroscopic analysis is an ideal method for this. If you’ve not already done so, you can download our free white paper on how mid-IR spectroscopy can be used to undertake this kind of analysis and how to create such a system. Alternatively, our 10-minute blog on the considerations is available here.

4) Testing rice for toxins

Rice is not only the most eaten food in the world, it is also the staple food crop for more than half the world’s population, and the most important crop for people in the developing world. That does come with significant problems, rice doesn’t contain vitamin A, which has a knock-on effect on several biological processes, especially immunity and sight. And while genetically modified strains are being bred to bring vitamin A into rice, there is a second problem.

Rice grains are often damaged through fungal spoilage as well as mycotoxin production, which comes as a result of poor post-harvest drying and inappropriate storage conditions, with aflatoxins being shown to be both toxic and carcinogenic – classified as a group I carcinogen by the International Agency for Research on Cancer (IARC). Because of its toxicity, past studies have tried to quantify the levels of aflatoxin in rice using chromatograms, but survey samples have been limited and can only highlight the scale of the problem, not help communities detect spoiled rice.

A new paper, published in June by Sirisomboon et al from Chulalongkorn University, shows how infrared spectroscopy has the potential to detect aflatoxins rapidly, meaning portable, low cost systems could be created for such communities to test samples throughout the year and then identify / share best practice among local communities to prevent the fungal infection from taking place.

As per the researchers’ findings, “The model developed showed good predictive performance which suggests that it [infrared spectroscopy] could have practical applications as a rapid method to detect aflatoxins in brown rice.”