Scientific Numbers in Logstash - How to handle them? Need help

Hi there,
I have found below mentions post which is a bit helpfull but I dont know how to split a Scientific Notation and merge them afterwards
.
A few examples of the numbers I want to handle or to learn how to handle in logstash:

2,3500000000000000E+02
-3,3000000000000000E+01
2500000000000000E+03

I tried also with grok but not yet found the right way:

(?<name-of-field>[([0-9] [+\-]? [0-9])]+)

Hope you can help me
Thanks and regards