Question: can dhikr be done without wudu?
Answer: It is not necessary to be in a state of wudu to engage in dhikr, or to recite one's daily litanies. It is, however, recommended to do so, such that one is in the best of states. This also goes for similar activities, such as reciting the Qur'an or reading Hadith, or engaging in the study of Islamic sciences.