Medicine cabinets of the future may one day contain a bottle of artificial tears developed at Oxford University.

Researchers at the Department of Ophthalmology have discovered and patented a combination of proteins and fats that make up the essential ingredients of human tears.

Tears play a vital role in the way the eye works, cleaning away dust or dirt. They also help break down harmful bacteria before they can cause infection.

Millions of people suffer from eye problems such as dryness, redness, inflamma- tion and scarring of the cornea caused by an inadequate supply of tears. The artificial product would be put into the eyes like eye-drops.

But the tears developed at the University are based on cow's milk, which could put people who suffer from milk allergies at risk.

Now Isis Innovation, the company that patents and finds venture capital for the University's research discoveries, is helping the department to develop its discovery. A major pharmaceutical company is looking at whether to carry out further studies.

Dr John Tiffany, a lecturer in ophthalmological bio- chemistry, who heads the research group, said: "It will be some time before the product is available to the public.

"It will have to be thoroughly tested and that will cost a lot of money. It would be rash to put it straight into production because of the risks.

"Anyone without a milk allergy would be fine, but many people don't realise they have one."