A Glaswegian entrepreneur has sold the rights to the bottle he developed for athletes to carry diet supplements in, in a deal that could be worth around £1 million.

Michael Devlin sold the intellectual property rights and patents for the Core 150 range to Tiger Global, which has been making the bottles in China.

The sale comes after Mr Devlin built a global following for the bottles, which athletes can use to carry protein supplements and the like. The bottles contain three trays that can be filled with powders, and then suspended vertically in a holder inside the bottle. The supplements can be mixed with water in the bottle.

Mr Devlin, 38, said Core 150 has sold around 320,000 bottles around the world since the range was launched in 2012, proving how quickly small and medium sized enterprises can grow sales in the digital age.

The company had revenues of around £400,000 in 2014 and traded profitably.

"I've managed it all online with a mobile phone and a laptop," he said.

Core 150 has built up a network of distributors in a range of countries extending from the USA to New Zealand.

Mr Devlin noted the company signed up licensees in Australia and South Africa before it had finalised the design of its first bottle, after coming to their attention on Twitter. The firms concerned provided orders that helped to underpin the development of the product.

"People loved the concept," he said.

London-based Tiger Global showed early faith in the concept by working with Mr Devlin to finalise a design that would be suitable for mass production. This process took several months and culminated in the launch of the Core 150 range in August 2012.

With a background in sales, Mr Devlin had the idea for the bottles after transporting bulky containers that held a sports nutrition supplement he had developed with US partners.

"I thought there had to be an easier ways of transporting things," recalled Mr Devlin.

The fitness enthusiast sold the rights to the supplement, Competitive Energetic Lifestyle, to the AFI manufacturing business.

After coming up with the idea of carrying servings of different supplements in a bottle in which they could be mixed with water, Mr Devlin spent months developing the concept with his business partner, Scott Millar, who is a product designer.

He honed his business skills in the Entrepreurial Spark hatchery for start ups in Glasgow.

"It was brilliant, mostly from a networking point of view," said Mr Devlin of ESpark.

He added: "The support of the enablement team was good. They act like your shrink."

Mr Devlin said he decided to sell the IP for the Core 150 range after retailers started to show interest in stocking the bottles. He thought moving into manufacturing on such a scale would involve a significant funding commitment and preferred to focus on using his marketing skills.

Under the deal agreed with Tiger Global Mr Devlin will have incentives to achieve digital marketing targets.

He is working on plans for a new web-based venture called the Profits Engine that expects to help SMEs harness the web and social media to grow sales. The venture has won £137,000 backing from a software developer.

While Core 150 sold overseas through wholesalers, the company sold direct to consumers in the UK over the web. It had UK sales of around £250,000 in 2014 and made a six figure profit on these.