Depending on how long you're going to leave the beer in secondary, you may want to tie the chips up in cheesecloth with some marbles to weigh it all down, so that it doesn't float and start growing mold. If it's only going to be in secondary for two weeks it's probably not worth worrying about though.
You can sanitize the whole thing if it makes you feel better, but I wouldn't worry too much about it.
Cheers,
Brian