That is done as a matter of course. Don’t reward them with Tenure. A short single term makes them much less valuable and will at least reduce the corruption. It will also change the selection of candidates. More businessmen will take two years off. More normal citizens will go for it. One inducement to corruption will wither and that is the guarantee that if you play along you get to increase your income if you lose your next election by going to work as a lobbyist. The temptations will remain. That is the nature of government work of any kind, but they will be much reduced.
I wonder if Senate terms should be shortened to, say, 4 years instead of 6? (Elect half with the President and half at midterms)
Although that would be a radical proposal requiring an amendment.