Which breeds for sniffer dogs

I was wondering if someone wishes to enhance security in an institution which type of dog would be good at detecting intruders as well as hidden weapons. Sniffer dogs are obviously the answer. I am at a loss as to which breeds make good sniffer dogs. I don't think that all breeds are suited for this. Do they (sniffer dogs) have unique requirements in terms of nutrition and health for example?

 

Police officers use German Shepherd and sometimes, Hound dogs to sniff out varieties of things, from bombs to drugs to whatever they want to train the dog to do. Depends on what you desire or your situation, certain smaller dogs are good sniffer too, such as Beagle.