Belfast nanotechnology drug delivery company SiSaf has appointed Irish-American businessman John Hartnett as its non-executive chairman.

Mr Hartnett is president and chief executive of solar energy company G24 Innovations and was previously global head of sales with smartphone maker Palm.

He is also president and founder of the Irish Technology Leadership Group (ITLG), a Silicon Valley-based network of Irish and Irish-American business people.

Last March SiSaf was recognised as having the most promising technology at the ITLG's annual awards which are sponsored by The Irish Times.