Nelnet director Chuck Norris has joined MindMixer's board.

MindMixer, a US-based online engagement platform for education and healthcare organisations, has raised $4m from a consortium led by Nelnet, a local education loans and service provider that has backed more than six start-ups.

The other investors were Dundee Venture Capital and investment firm Optimas Group. In aggregate, MindMixer has raised $6.2m, including $1.9m led by Dundee last year.

Mike Dunlap, chief executive of Nelnet, said: “Nelnet is always looking for ways to improve the way we help associates, students…