A man has been arrested following a BBC investigation into the sale of the Class B drug mephedrone at the University of Sussex.
Sussex Police said the 19-year-old, who had been living in Brighton, was arrested in Essex on Tuesday evening.
He is currently being questioned by officers over the supply of drugs.
During a BBC investigation an undercover journalist purchased two grams of mephedrone from a dealer for £55 on the university campus.
Following the BBC South East Today report the university announced that they had suspended a student.
Prof Michael Farthing, vice-chancellor of the university said: "The university does not tolerate drug-dealing or illegal drug-use on campus.
"We generally have a very safe campus. There is no evidence that drugs are any greater problem for Sussex than elsewhere in the UK."
Mephedrone was made illegal on 16 April on the advice of the Advisory Council for the Misuse of Drugs.
The drug has been linked to at least 22 deaths, but there has been no conclusive scientific proof yet that it has been the cause of any of them.