His discovery started commercial production of the so-called ''rice starch'', a kind of pure rice flour, which is now used as a filler to produce drug tablets.

Rice starch is extracted from broken rice by pulling out its proteins to get pure carbohydrate flour. Normally, it's used as thickener when making sauces and desserts, and it can also be hydrolysed to make sweet syrup.

Saiyavit said he made the experiment using the starch as filler in drug tablets and unexpectedly found that the starch's properties could make the tablet hold its shape and release the drug more completely.

"It's a discovery that we never expected, and this made us the world's first to find a better material to use as a diluent in the drug industry," he said.

For his research, Saiavit was honoured by the Foundation of the Promotion of Science and Technology under the Patronage of His Majesty the King as the country's "Outstanding Technologist of 2006".

According to the study, using rice starch as tablet filler will help the tablet have better crushing strength and importantly, when it reacts with water, it can dissolve and release the drug's key ingredient to tackle the disease much faster.

He said that drugs with rice starch filler will dissolve within 30 seconds and can release 100 per cent of the drug.

"Rice starch offers better properties when compared to other tablet fillers including lactose or cellulose, which dissolve more slowly and cannot release 100 per cent of the drug," he said.

To make rice starch suitable for the drug production process, Saiyavt also adopted a technique called ''spray drying'', which reshapes the starch's molecules. He said the starch molecules after spray drying become more spherical, with a radius of 50 to 80 microns. This offers better free flowing properties when it comes to the drug production process.

The research has added more value to the rice industry in Thailand.

"More value can be added to broken rice products, the by-product from rice milling processes. Normally, the broken rice is sold as animal food at only Bt10 per kilogram, but the rice starch can be sold at Bt100 per kilogram, ten times more," he said.

Importantly, the rice starch can be sold to the pharmaceutical industry not only in Thailand, but also exported to the international market.

With high business potential, Mahidol University has a joint venture with a private company to set up the Erawan Pharmaceutical Research and Laboratory to produce rice starch for commercial use. So far, the company can produce 10 tonnes a month, making Bt1 million in revenue. 

The demand for rice starch as a tablet filler is always growing. This is because it offers not only better properties, but also a lower price when compared to the existing filler materials.

"Normally, pharmaceutical companies have to spend Bt400 to Bt500 per kilogram to buy filler materials like lactose or cellulose, but with rice starch, they pay only Bt100," Saiyavit said.

Apart from being tablet filler, he said rice starch could also be adapted for use in the cosmetics industry.

The starch, he said, is expected to be a new filler to replace the existing talcum to produce cosmetics and baby powder.

Talcum is a mineral composed of hydrated magnesium silicate with a chemical formula. As it has a soft, soapy feel, it is mixed in baby powder.

However, it's known that particles from talc, when used for a long time, will cling inside a human's lung, so there is a recommendation that talc should not be inhaled over a prolonged period of time.

Saiyavit said rice starch would therefore be a new alternative and this would open up more business opportunities.

Rice starch is biodegradable, so its particles can be dissolved biologically with nothing left inside the body.

Erawan Pharmaceutical Research is planning to adapt rice starch to produce a new kind of powder that is talc free. The product is expected to hit the market next year.

Pongpen Sutharoj

The Nation