Contact lenses made with millions of gold nanoparticles, no bigger than a speck of dust, could combat a common type of colour blindness.
These ‘gold dust’ particles filter out certain wavelengths of light, so the brain can distinguish between different colours, particularly reds and greens, more easily.
Around one in 12 men and one in 200 women struggle with this condition, called ‘red-green colour vision deficiency’, the most common type of colour blindness.
It’s more frequent in men as it’s passed down on the X chromosome (men have only one X chromosome, from their mother, and if that has the gene for colour blindness, they will be affected; women would need to inherit the gene from both parents to be affected).
Contact lenses made with millions of gold nanoparticles, no bigger than a speck of dust, could combat a common type of colour blindness
The genetic defect means some colour-sensitive cells at the back of the eyes, called cones, are missing or do not work properly. It can also come on later in life, due to conditions that damage the eye, such as diabetes or glaucoma. Some prescription medicines — such as sildenafil (Viagra) — can also affect colour perception.
When light hits the back of the eye, the cones separate out all the colours and pass the information to the brain.
If the cones are missing or damaged — for example, in red-green colour blindness, the cones that detect red and green tones are affected, and the rays of different colours can overlap or merge together where they hit the eye — it is difficult to tell them apart.
In red-green colour blindness, the cones that detect red and green tones are affected, and the rays of different colours can overlap or merge together where they hit the eye — it is difficult to tell them apart
Red-tinted glasses can help by filtering out some of the light as it enters the eye, reducing the amount of overlap and effectively increasing the contrast between the colours.
The problem is these glasses are bulky and the lenses are dark red, which can make them unsuitable for everyday wear.
The new contact lenses, however, are more discreet and have only a slight pink hue. They appear pink (rather than gold) because, in tiny fragments, gold has a small surface area and so, rather than reflecting the whole spectrum of light (which would make it appear gold and shiny), it reflects more red light, which makes the lenses look rose-tinted.
Until now, attempts to make contact lenses have had limited success. This is partly because the dye deployed in spectacles can leach into the eye when used in a contact lens, reducing its effectiveness.
Scientists at Khalifa University, UAE, and Imperial College London, experimented with gold particles as the metal is safe to use in the body.
To make the contact lenses, the team mixed gold particles into hydrogel polymer, the material used for standard contact lenses.
In a lab study, the lenses blocked at least 50 per cent of the light that mixes reds and greens, reported the journal ACS Nano, making it easier to tell the colours apart.
Melanie Hingorani, a consultant ophthalmologist at Moorfield’s Eye Hospital, London, says: ‘The lenses may help some people with colour blindness, in the same way tinted glasses do, but they are not a cure.’
Try a workout for a better night’s rest
A workout won’t just give you tired muscles — researchers have found that it improves the quality of your sleep, even though most people won’t notice the difference it makes.
Researchers from the University of Tsukuba, Japan, used a computerised method to record brain signals to determine the depth of sleep.
Nine volunteers did a 60-minute workout and were then connected to the technology as they slept. The participants had deeper and more refreshing rest when they had exercised — although the volunteers reported no change.
Writing in the journal Scientific Reports, the researchers say their work may help develop new treatments for sleep disorders.
A workout won’t just give you tired muscles — researchers have found that it improves the quality of your sleep, even though most people won’t notice the difference it makes
Anti-bacterial plaster made of recycled waste
Sc ientists at the Nanyang Technological University, in Singapore, have developed a gel ‘bandage’ made from waste — durian fruit and glycerol from soap manufacture — which they say offers an environmentally friendly and safe way to treat wounds
The product is made by processing durian husk, which is usually discarded, with baker’s yeast (which is antimicrobial) to form a hydrogel patch. These are used for wounds as their high water content promotes healing.
The journal ACS Sustainable Chemistry & Engineering reports that the gel created is similar to silicon sheets, that can be cut to size.
New drug to tackle virus that causes cold sores
A drug that treats a rare enzyme disorder could help treat the herpes virus that causes cold sores.
When the drug — called phenylbutyrate — was used along with acyclovir (a treatment for herpes), the combination cleared the virus, which also causes genital herpes, faster than when either was given alone, a study by the University of Illinois, U.S., found.
The researchers say that as the drug is licensed, it could be available for treating herpes faster.
A drug that treats a rare enzyme disorder could help treat the herpes virus that causes cold sores [File photo]
Can blackcurrants steady blood sugar?
Eating blackcurrants may help tackle type 2 diabetes, say researchers from the University of Eastern Finland.
In a study involving 26 volunteers, scientists found just 75g reduced blood sugar and insulin levels for half an hour. They say this suggests the fruit could help regulate the body’s blood sugar response, and reduce the risk of type 2.
Blackcurrants contain anthocyanins, a type of antioxidant which can prevent damage to cells. It’s thought anthocyanins may inhibit the enzyme that helps to break down sugar.