There are much better 'disinfectants': alcohol is good at killing living cells, but doesn't do a great job killing spores or penetrating into protein-rich....gunk.

You would probably want to use a "high-level disinfectant" or "sterilant" instead. Gluteraldyhde is fairly common choice or ethylene oxide gas, though both can be fairly nasty if not handled carefully (which is, of course, the whole point).