Allah does not accept the prayer of anyone of you who is in the state of Hadath (minor ritual impurity), until he performs ablution. [Al-Bukhari ]
"عن أبي هريرة -رضي الله عنه- قَالَ: قَالَ رَسُولُ اللَّهِ -صلى الله عليه وسلم-: ""لاَ يَقْبَل الله صلاَة أَحَدِكُم إِذا أَحْدَث حَتَّى يَتوضَّأ"". [صحيح.] - [متفق عليه.]"