Black Cats boss Roy Keane confirmed on Monday that the club have made a bid for Tottenham's Egypt striker Mido.
And Quinn told Radio Five Live on Tuesday: "This is Roy's department really but we are trying hard - there are lots of bits and pieces going on behind the scenes.
"If it takes a bit longer so be it - we are not going to lose our nerve now.
"My message to our fans is that we haven't jumped in when an agent has rung us with a fashionable player.
"A lot of things have to fall right for someone to come to play at Sunderland."