Money from an oil-rich emirate has ended up in a Puget Sound venture that seeks to produce cleaner water.

An Abu Dhabi government-backed clean technology fund is investing $15 million in Bothell-based HaloSource, a company that specializes in anti-microbial water purification. The new relationship will help strengthen HaloSource's presence in Middle Eastern markets.

The deal underscores how some Persian Gulf countries - flush with cash in the wake of an unprecedented energy boom - are spreading investment dollars not only across the region, but all over the world. They also seek to capitalize on the growing global interest in clean technologies and sustainable development.