One of the major hurdles for finding a job is having "industry experience" and contacts who work in industry. We often bemoan that grad students in biology can't do internships to fill those gaps, but I am starting to think, why not? Sure, you might delay graduation by a couple months- but who hasn't had a few months where nothing works in grad school? And your boss will probably not understand why you want to intern. But unless your boss has tons of contacts in industry that are going to help you make the jump when you are ready, you might need to make a selfish choice.
And lest you think that such a thing doesn't exist, I will correct that with a list of companies that do offer internships for graduate students who are pursuing a degree in the life sciences. With a little work, you can probably find one that isn't a total waste of your education, too.
USDA and FDA
Perhaps you have heard of some of these employers? These are just what I came up with in a couple minutes on Google. If you can imagine that you might be interested, now is the time to apply for summer internships. Now may also be the time to suggest to your boss those in vitro experiments won't be wrapped up until the fall.