Can I still use my bottle?

About a week or so ago one of my daughters bottles fell behind my nightstand while it was still half full. I didn’t realize it was back there until I was plugging something in and saw it. obviously the formula had gone bad, I cleaned it thoroughly with soap and scolding water and ran it through the sanatizer but the bottle itselef still smells like bad formula. Would the smell effect anything? Can I still use it? It’s one of my better (and more expensive) bottles and I would really hate to trash it!