Rise of the machines?

Rise of the machines? Snuff and nonsense says Russ Swan – when it comes to sensors, there is an awful lot to be said for us meat bags…

Bad news for the manufacturers of laboratory instruments, I'm afraid. Despite the extreme cleverness they manage to build into modern instruments, with lower detection limits and higher resolution packaged into increasingly pretty and compact boxes made available at lower cost and with longer service intervals, it is all in vain. The age of the machine sensor is over. Welcome to the new era of the home-brewed biological sensor.

Now, readers of this august journal are all too aware that there is a world of difference between an instrument and a sensor. Many standard scientific instruments have no sensor as such, relying on the human operator for this most important of tasks. The light microscope is the classic example, where the machinery merely feeds photons into the Mark 1 Human Eyeball for analysis. The same is true of telescopes, and early chromatography and spectroscopy instruments were mainly concerned with separation of their input for subsequent detection by manual optical methods. The biosensor is what laboratory analysis began with.

But that's all ancient history, isn’t it? In this age of scanning tunnelling electron microscopy and time-of-flight mass spectrometry, of multi-megapixel CCD sensors and nanotechnology, surely there is no place for slightly shambolic nature of the organic detectors actually built-in to living people? The machines have already taken over, haven’t they?

Not quite yet they haven't – and it seems they aren’t going to do so any time soon. The human visual sense, coupled to its image processing system, remains the most powerful detector in the known universe, which is why it is deployed on challenging citizen science projects like Galaxy Zoo, and more recently in scanning high-resolution images of comet 67P to find the peripatetic Philae lander.

The news published in December in the US Proceedings of the National Academy of Sciences that human eyes can also see 'invisible' infra red light under certain conditions, coupled with the experiences of astronauts who report seeing strange flashes of light – later determined to be cosmic rays hitting the retina – makes it seem that there may yet be untapped detection potential in the human eye. What other human sense could possibly rival the power of vision?

It's no joke when I tell you that the answer is as plain as the nose on your face.

I was prompted to this thinking by a presentation at November's Lab Innovations show. Despite the array of modern instrumentation available to it, food and drink analysis laboratory Campden BRI relies heavily on organic devices to determine the chemical composition of its samples. Specifically, the human nose is its ace in the hole, its killer app, its big selling point.

The human, apparently, has a quicker response and a more meaningful output than the machines, and can make a determination of 'acceptability', whereas the machinery simply spews out some numbers (although these do offer numeric precision, which the human does not). Having snorted a dozen or more samples from glass vials provided at the presentation, I understood the advantage of the human ability to use language instead of numbers (and I felt like the star pupil when I was the first to suggest 'pond water' for a sample – something the machinery couldn't do).

Human noses are as nothing compared to the canine version, which is why they let dogs sniff your bags at airports and security checkpoints. Now, if only there were some way to enhance the human sense of smell, rather like our optical instruments enhance our sense of sight. With such a technology, a whole new world of scientific discovery would await us.

Ladies and gentlemen, it is an honour and a privilege to introduce you to the Nasal Ranger. This is without question the most stylish and innovative item of chemical detection paraphernalia we've seen this month. It is a state-of-the-art field olfactometer, which I think explains pretty much exactly what it does: measures smells in the field.

Fans of the cartoon series Futurama may immediately spot a similarity to Professor Farnsworth's Smell-O-Scope, a 30^th-century device which allows users to detect odours over cosmic distances (and prompting the inevitable 'I can smell Uranus' gag sequence). But be not misled, for the Nasal Ranger is an actual thing, used for actual investigation (largely the detection of narcotics, if you go by the references on the company's website).

I can’t help thinking that this is the next item of must-have lab equipment, with only a passing sadness about all the springer spaniels that will be put out of work as a result. Your new business attire for 2015: lab coat, goggles, nitrile gloves, and a nose trumpet. Smell you later.