fluid damages can do serious damage to the phone
there is a white/greenish residue that shortens the parts, this residue must be removed
disassemble the phone, use one of the guides from te right (you didn't wrote what iphone model you have - thats why i can't provide a direct link for that)
use isopropyl alcohol (>90%) and a soft paintbrush to carefully clean the parts, don't forget the connectors
let the phone dry - without a hair dryer
reassemble it and try to power it on
good luck