I've been playing Batman: Arkham City and there is a Riddler Proximity Mine in the Secret Corridor in Wonder City. I've tried to disable it using the Disruptor (as suggested in the answer to my previous question about disabling Proximity Mines) but it doesn't work (I'm aiming with LT and pressing RT, but there comes the "no sign" ).
I've also tried to find a way to that room which stores the Riddler Trophy, but to no avail (I've taken a look inside the room by throwing a remote batarang in it).
The only way in seems to slide under the bars but the mine must be disabled first. How can I achieve this?
Below are two images I took with my good old cellphone. Sorry for the low image quality.