Take the thickest part you can possibly find and at least 8" long and soak it in some denatured alcohol or methanol (methanol is toxic, use caution, but it's $2 a gallon vs. the $15 for DNA). Soak it for a couple of days and then let it air dry somewhere that a bit of potentially rotting pumpkin won't offend any spouses or roommates. Out in the sun would work if it weren't November.
After it's dried as much as it can (which will take a while) stabilize it with PR or something similar (perhaps plop it in a small dish filled with thin CA and pull a hard vacuum on it).