How To Detect Fluoride In Drinking Water

A simple colour-changing test to detect fluoride in drinking water, devised by researchers at the University of Bath (UK), could in the future prevent the crippling bone disease, skeletal fluorosis, in developing countries such as India and Tanzania. Whilst low amounts of fluoride are beneficial for healthy teeth, high levels of fluoride can weaken bones, leading to skeletal fluorosis. This disease causes crippling deformities of the spine and joints, especially in children whose skeletons are still forming.

When water passes over certain minerals, it can dissolve fluoride, which results in elevated levels of fluoride in drinking water sources in parts of East Africa, India, China and North America. Levels of fluoride in drinking water are routinely monitored and controlled at treatment works in developed countries. However in areas of the world where there is no piped water system or treatment works, people rely on drawing untreated water from wells, which can often be contaminated with higher than recommended levels of fluoride. The amounts of fluoride in the groundwater can vary due to weather events, with levels fluctuating hugely when there is a lot of rain.

A research team at the University of Bath’s Centre for Sustainable Chemical Technologies, and the Water Innovation and Research Centre (WIRC), led by Simon Lewis, has developed a simple colour-changing test that detects high levels of fluoride quickly and selectively. Whilst the test is at the proof of concept stage, the team aims to develop it into a disposable test strip that is low cost and easy to use by anyone.

The test changes from purple to blue when the levels of fluoride in the water are too high (click to get video)

Lewis explains: “Whilst a small amount of fluoride is good for your teeth and prevents tooth decay, high levels are toxic and can cause crippling deformities that are irreversible. “Most water quality monitoring systems need a lab and power supply and a trained operator to work them. What we’ve developed is a molecule that simply changes colour in a few minutes which can tell you whether the level of fluoride is too high. “This technology is in the very early stages, but we’d like to develop this technology into test strips, similar to litmus paper, that allow people without any scientific training to perform a test that is low cost, rapid and robust. “We anticipate that in the future it could make a real difference to people’s lives.”

I am very enthusiastic about the newly developed indicator molecules and am convinced that they can be incorporated into an easy to use technology that is able to provide instant information on the safety of drinking water with regards to fluoride,” comments co-investigator Dr Jannis Wenk, of the Department of Chemical Engineering and Water Innovation and Research Centre (WIRC) at Bath.


Gene Researchers Have Created Green Mice

These are no Frankenstein mice. Their green feet come courtesy of a fluorescent green jelly fish gene added to their own genome. This allows a team of British scientists to test out gene editing using CRISPR-Cas9 technology.


“We take what were or would have been green embryos and we make them into non-green embryos, so it’s a really great way of demonstrating the method“, said Dr. Anthony Perry, reproductive biologist at the University of Bath.

The technique uses the ribonucleic acid molecule CRISPR together with the Cas9 protein enzyme. CRISPR guides the Cas9 protein to a defective part of a genome where it acts like molecular scissors to cut out a specific part of the DNA. This could revolutionise how we treat diseases with a genetic component, like sickle cell anaemia. The technique is being pioneered in the U.S.
We now have a technology that allows correction of a sequence that would lead to normally functioning cells. And I think you know the opportunities with this are really exciting and really profound. There are many diseases that are have known genetic causes that we now have in principle a way to cure,“explains Jennifer Doudna, Professor of cell biology at the University of Berkeley.
Last year two teams of U.S. based scientists used CRISPR-Cas9 technology in mice to correct the genetic mutation that causes sickle cell disease. Although researchers aren’t yet close to using CRISPR-Cas9 to edit human embryos for implantation into the womb – some are already warning against it.

Dr David King, Director of  Human Genetics Alert, comments: “It will immediately create this new form of what we call consumer eugenics, that’s to say eugenics driven by the free market and consumer preferences in which people choose the cosmetic characteristics and the abilities of their children and try to basically enhance their children to perform better than other people’s children.” Other potential applications of the technology could be to make food crops and livestock animal species disease-resistant. The British team say CRISPR-Cas9 presents a golden opportunity to prevent genetic disease.


Nano-Robots Enter Living Cells

Researchers have developed the world’s tiniest engine – just a few billionths of a metre in size – which uses light to power itself. The nanoscale engine, developed by researchers at the University of Cambridge, could form the basis of future nano-machines that can navigate in water, sense the environment around them, or even enter living cells to fight disease. The prototype device is made of tiny charged particles of gold, bound together with temperature-responsive polymers in the form of a gel. When the ‘nano-engine’ is heated to a certain temperature with a laser, it stores large amounts of elastic energy in a fraction of a second, as the polymer coatings expel all the water from the gel and collapse. This has the effect of forcing the gold nanoparticles to bind together into tight clusters. But when the device is cooled, the polymers take on water and expand, and the gold nanoparticles are strongly and quickly pushed apart, like a spring.


It’s like an explosion,” said Dr Tao Ding from Cambridge’s Cavendish Laboratory, and the paper’s first author. “We have hundreds of gold balls flying apart in a millionth of a second when water molecules inflate the polymers around them.
We know that light can heat up water to power steam engines,” said study co-author Dr Ventsislav Valev, now based at the University of Bath. “But now we can use light to power a piston engine at the nanoscale.”

The results are reported in the journal PNAS.


Nano Pacemaker To Extend Cardiac Patients Life

A new type of pacemaker develped by a research team from the University of Bath and the Univerity of Bristol – U.K. – could revolutionise the lives of millions people who live with heart failure in the world. The British Heart Foundation (BHF) is awarding funding to researchers developing a new type of heart pacemaker that modulates its pulses to match breathing rates. Currently, the pulses from pacemakers are set at a constant rate when fitted which doesn’t replicate the natural beating of the human heart. The normal healthy variation in heart rate during breathing is lost in cardiovascular disease and is an indicator for sleep apnoea, cardiac arrhythmia, hypertension, heart failure and sudden cardiac death.
The device works by saving the heart energy, improving its pumping efficiency and enhancing blood flow to the heart muscle itself. Pre-clinical trials suggest the device gives a 25 per cent increase in the pumping ability, which is expected to extend the life of patients with heart failure.

This is a multidisciplinary project with strong translational value. By combining fundamental science and nanotechnology we will be able to deliver a unique treatment for heart failure which is not currently addressed by mainstream cardiac rhythm management devices,” explains Dr Alain Nogaret, Senior Lecturer in Physics at the University of Bath.
One aim of the project is to miniaturise the pacemaker device to the size of a postage stamp and to develop an implant that could be used in humans within five years.
The findings of the research have been published recently in the Journal of Neuroscience Methods.