What is the ruling on taking ablution before go to bed at the night? Please clarify with authentic Hadith if there is any?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Among the Sunnah that is recommended for the person to do before going to bed is to perform ablution.

The Prophet said: “When you intend to go to bed, perform ablution as you do for the prayer.” [Al-Bukhari and Muslim]

Allah knows best.