A Hong Kong-born scientist believes he may have discovered a golden cure for cancer. Associate Professor Leung Pak-hing, a research fellow at the National University of Singapore, is poised to patent the formula for a new family of drugs made from phosphorous and gold. The phosphorous targets the sulphur content of poisonous cancer cells. The gold then kills them off. The technique, still in the exploratory stages, is being hailed as a potential major medical breakthrough. 'Our target is to remove the whole cancer,' said Professor Leung, 43, who was brought up in Taikoo Shing before going abroad to study and work. The drugs have been tested on mice with few or no side effects, unlike existing treatments such as chemotherapy which can cause nausea, hair loss, and liver and kidney damage. Tests on humans have not yet been carried out. Since announcing his breakthrough, Professor Leung has received a string of calls from cancer-sufferers offering themselves as 'guinea pigs'. 'I have had to turn them down, saying it is still too early,' he said. 'There are proper medical procedures for doing such things.' Professor Leung, a chemist, is being helped with the testing by Associate Professor Chan Soh Ha, an award-winning National University of Singapore medical scientist. They say they are avoiding pharmaceutical companies until the university has completed the patent. Even if all goes well, it could still take another five to 10 years before the drugs come on the market. After just one simple injection, cancer cells in 20 to 40 per cent of mice were reduced to the point where they no longer became detectable. Once sophisticated methods of administering the drug have been developed, the professors hope the success rate with humans could be in the 80 per cent range. Out of the 50 drugs the Singapore team have come up with so far based on the gold-phosphorous formula, two have shown great promise with various types of cancers such as lymphoma, leukaemia and liver cancer. Professor Leung is a Singapore resident, after moving there about 10 years ago. He studied in London, before completing a doctorate in Australia, then worked in Canada and the United States.