You may use anything you like; I use denatured alcohol on a lot of things but not my guns. I did use Gun Scrubber before taking the advice of my gunsmith. To be more specific I have read that denatured alcohol can damage o-rings, wood finish, and isn't as effective at removing powder residue as designated gun cleaners and solvents. The following is a quote from a USMC Captain:
"I would recommend you use solvents designed to clean firearms and leave the home remedies for the end of the world and redneck survivalists." A bit harsh perhaps but he has a point. Even though Frog-Lube solvent and LPS Micro-X seem expensive it takes very little to clean a gun and I have cans that are years old with cleaner still in them.