A knife arch was in place at Maggie's, on Commercial Street, over the weekend making sure no one could bring a weapon inside.
The equipment scans people as they walk through and is used to check for blades.
Police said the move was part of Operation Sceptre - a knife crime awareness week.
Officers posted on social media: "Officers attended Maggie's and deployed a knife arch to prevent anyone from entering the premise who may have been in possession of a knife.
"The knife arch was deployed as part of the Op Sceptre - knife crime awareness week this week."
Police also held a talk for more than 160 teenagers to educate them on the dangers of knife crime.
A teacher from one of the schools whose pupils attended said: "Our students and myself really enjoyed it and definitely took things on board. It’s all they spoke about in school in the afternoon.”