Looking for a CYOA that might not have been a CYOA about a shrink belt

Question

Okay I think this book might be lost media at this point. I am looking for an interactive story that may have been a CYOA but might not have been that brand. It's about you getting a shrinking belt to help out a friend of yours who works at a particle accelerator to catch a potential terrorist that wants to use a belt he stole to steal secrets.

It looked incredibly old when I read it and that was like 15 years ago. I remember a few of the endings, one was you shrink into a small terrarium in the lab and are killed by an ant, another is you shrink further and get attacked by an amoeba and when you grow you are scarred and become a horror movie star. In another you are crawling in the ducts and this guy you are chasing is able to get in your ear after you get stuck and keeps singing show tunes until you give up on your mission.

The most memorable one was you go into the particle accelerator and you are fighting him on some protons and he pulls out and he threatens to reverse his atomic polarization with his belt and before you can stop him he gets hit by a proton and he turns into antimatter and explodes like a nuke destroying the whole facility.

It was a very cool adventure but I have been unable to find it for years, I remember the front cover looking very faded with a lot of reds, I think it had the particle accelerator on the front as well.

Answer 1

I came here wracking my brain also and figured it out from the above suggestions by Astrid. Well at least the belt and the fight with the guy trying to turn into your anti particle.

It's Journey to the Center of the Atom.

The reader's decisions will determine what will happen when a special scientific team shrinks themselves to subatomic size in order to find the smallest particle

I also remember this book being so cool. I think it introduced me to the concept of gluons. Crazy.

"Get out of my ear!" you scream.
“Heeee! Heehee!" The intruder’s giggling is unbearable. He’s beating a rhythm on your eardrum and singing the television jingle you hate the most.

"I’ll never leave unless you give up this project," he tells you. "No matter how much you shrink or grow, I’ll stay right here in your ear."

"Buzzzz, hummm, dum de deedle dum. . . The noises and chatter, singing and itching, wheedling and needling, are driving you crazy. After 17 hours you resign from the project and go into writing television commercials full-time.

Answer 2

Could this be the CYOA book You Are Microscopic by Edward Packard?

On hand when a brilliant scientist unveils his latest invention--a machine that shrinks human beings--the reader is shrunk to a miniscule size and must fight such fierce foes as house flies

This review mentions getting attacked by an amoeba.

A little knowledge of the scientific world can help you make better choices in this book. For example, I knew better than to jump onto a "jelly blob" in the pond when I was teeny tiny (it turns out to be an amoeba that chomps you up!)