Can the state or anyone seize my property or assets for my 37 yr old sons back child support?

You need more specifics - what state, and when was the court order for support?
It isn't clear whether you owe your ex for support of your son long ago, or whether your son owes his ex for his child. (If it's the latter, no one can take your property, unless he recently put his property in your name to hide it.)