Spraying alive: From liquid plasters to spray-on tooth enamel, how a little squirt can now work miracles
23:03 GMT, 27 August 2012
Sprays are a constant feature in our daily lives — they make us smell sweet, keep our kitchens sparkling and fix our hair.
And they may even save our lives.
Doctors have known for some time that drugs can be delivered by a spray, particularly to the mouth or up the nose where they are absorbed faster into the bloodstream.
Life saver Doctors have known for some time that drugs can be delivered by a spray
But scientists have now developed a range of sprays that can help repair body parts, heal wounds and prevent post-surgery complications.
‘Sprays are much easier and less messy to use than ointments and lotions,’ says Sam Shuster, professor of dermatology at Newcastle University.
‘But, more importantly, they allow more accurate and consistent delivery of the drug or treatment, and allow it to be held in the controlled sterile environment of a spray can,’ he adds.
Here, we reveal how sprays are transforming medicine.
LIQUID LYCRA BANDAGE
Researchers have developed a spray-on bandage for minor cuts and scrapes that helps to keep them clean and free from infection.
Based on a plastic that is used in Lycra, called polyethylene glycol, the thick liquid is sprayed on to the wound and sets within five minutes.
When the plastic sets it pulls the edges of the wound together, aiding healing and helping to prevent infection.
The consistency allows oxygen to penetrate the dressing, further aiding wound repair.
The bandage has been given approval from the U.S. Food and Drug Administration and the developers hope to launch it in UK within three years.
‘Cuts in the skin, especially small ones, can be stuck together this way and will heal well,’ says Professor Shuster.
‘But the bigger ones can get infected, and for these an old-fashioned dressing that can be removed, so the wound can be cleaned, will allow faster healing.’
Spray-on teeth contains a type of calcium and helps repair damage to the tough outer coating of teeth – the enamel – and may help repair any exposed dentin
Spray-on teeth are being developed by scientists at King’s College London and Imperial College London.
The spray contains a type of calcium and helps repair damage to the tough outer coating of teeth — the enamel — and may help repair any exposed dentin.
This is the soft layer under the enamel that can become exposed through wear and tear and trigger sensitivity.
The developers say the product blocks tiny tubes in the dentin, which can reduce sensitivity.
The spray is held a few millimetres from the teeth and projects a dry powder — the action of the powder hitting the teeth also acts as a mild abrasive, helping to remove stains.
Researchers are also investigating whether the spray can be applied to damaged bone during orthopaedic surgery to aid regeneration.
ORGAN OIL SPRAY
Scientists have devised a non-stick coating for organs that prevents them sticking together after surgery.
The coating, which is also being used to preserve objects salvaged from the wreck of the Tudor warship the Mary Rose, prevents adhesions — a common side-effect of surgery that causes tough scar tissue to form between organs, which pulls them out of shape.
An estimated 75 per cent of post-surgical small bowel obstructions and 48 per cent of chronic pelvic pain cases are caused by adhesions.
The surgeon coats the surgical area with polyethylene glycol.
This provides a slippery coating around the organs and prevents the cells from latching on and forming scar tissue.
The coating breaks apart within a week — the period in which adhesions usually form.
A study of cases where the spray has been used showed that 90 per cent of patients were adhesion-free seven days after surgery.
A trial at Loma Linda University in the U.S. is looking at a similar product for use in adhesions in paediatric heart surgery.
‘Adhesions can be a great problem after surgery, particularly bowel and joint surgery, when scar tissue tries to repair the surgical wounds but does it too enthusiastically by joining parts that should stay separate.
'This new approach could be the answer,’ says Professor Shuster.
LEG ULCER SPRAY
A spray made from a patient’s skin cells has been shown to speed up the healing of hard-to-treat leg wounds.
Compression bandages work for up to two-thirds of patients, but are not completely effective.
The treatment, developed at Texas University, combines two types of skin cells, keratinocytes and fibroblasts, taken from the patient.
Results from a trial of 200 men and women with venous leg ulcers shows, after three months, patients given the spray therapy had a 15 per cent greater reduction in the size of the wound areas compared with those who had a placebo spray or compression bandages.
Large wounds are often hard to treat because skin cells cannot grow over such a large area.
But scientists believe that by spraying the cells on the wound, they provide a scaffold on to which other cells can grow.
Meanwhile, scientists have also developed a device that fires stem cells into burns injuries and can repair damaged skin in days rather than weeks.
At present, skin cells are taken from patients with burns and grown over a period of up to two weeks into sheets of new skin, which are then surgically attached to the wound.
But there can be problems, including blisters that can form under the new skin and push the sheet up, causing damage.
A spray is simpler to apply than a sheet of skin.
A silicone spray is being used to treat burn scars. Doctors believe a daily spray will improve their texture and colour.
In a U.S. Army Institute of Surgical Research trial, patients will be treated with the spray or a placebo each day for three months.
It’s thought silicone can work by keeping more moisture sealed inside the skin and reducing inflammation. It may also reduce the production of fibrous collagen that can lead to thicker, more prominent scars.
Professor Shuster says: ‘If it proves correct it could be quite an advance, because the irregular scarring of a healing burn has a poor appearance and often contracts, leading to impaired movement.’
BLOOD IN A CAN
Doctors are spraying patients with a natural blood compound to dramatically reduce blood loss after surgery.
The spray contains fibrin, part of the body’s own repair system that provides the ‘scaffolding’ for blood clots.
When a wound occurs, fibrin is released into the bloodstream and helps build the clot that seals the wound.
Doctors at the Royal National Orthopaedic Hospital, Stanmore, used the spray on patients undergoing hip replacements and found it reduced blood loss by 32 per cent.
Scientists have also developed a new anti-bleeding spray based on an acid that stops the body breaking down blood clots.
Results from one study shows that orthopaedic patients who were treated had 30 per cent less blood loss and did not need transfusions.
Surgeons at the University Hospital of North Tees and Hartlepool are carrying out two clinical trials involving patients undergoing knee or hip replacements.
The acid, called tranexamic acid, blocks the action of molecules that attack fibrin.
These molecules are part of the body’s defence system that prevent blood clotting in the arteries of the body — but the system can go into overdrive following the trauma of a large operation.
A spray-on foam has been developed to halt bleeding and keep wounds sterile. It has the consistency of shaving foam and is sprayed on to the wound.
Once out of the can it expands and fills the cavity in the damaged tissue to seal and protect it.
The spray is based on chitosan, which is derived from chitin found in the shells of crabs.
The spray sticks in place and can encourage growth of skin cells, says the manufacturer, which hopes to launch it in the UK next year.
The foam also allows oxygen to reach the wound, stimulating healing.