London, April 12 : Chinese researchers have devised a way to provide baker's yeast cells with the ability to survive longer in harsh environments.

Zhejiang University chemists say that they have basically developed egg-shell-like coats that can protect cells.

"Inspired by egg-shells, we wanted to give any individual cell a mineral coating to protect it. We selected yeast because it is a typical accepted model for cells," New Scientist magazine quoted lead researcher Ruikang Tang as saying.

The researchers created the mineral coat by using a technique called 'layer-by-layer deposition', which involves depositing alternating layers of oppositely charged polymers onto a surface.

They say that the tough calcium phosphate mineral shell thus created provided highly effective protection to the yeast cells during the armour-plating process.

Eighty five per cent of encased cells survived longer than a month in water, and endured attack from cell-wall-digesting enzymes, while less than 20 per cent of unprotected cells could survive that treatment.

Tang's group also found that incorporating iron oxide particles into the shells made the cells magnetic, which meant that they could be easily moved around with the help of magnets.

The finding attains significance because previous studies have already established that magnetic objects can be steered through the body, and that magnets can be used to target cancer drugs.

Based on this observation, the research team came to the conclusion that armoured cells seemed to offer a highly precise drug delivery system.

They now plan to work on giving other micro-organisms protective shells, and to explore a range of potential applications for the technique, including using the shell as a vehicle to deliver therapeutic cells to damaged tissues.

A report describing the study appears in the journal Angewandte Chemie.

ANI