You don't show which part of the world you are in. I am in Canada where I use American 2Nxxxx transistors. People in Europe use BCxxx transistors. People in the Orient use 2SCxxxx transistors.please tell me whch transister would be able to deliver the amount of current required in my project.
I would drive the 9 LEDs from the collector of a 2N4401 transistor. Each blue LED needs a 100 ohm resistor in series from the +5V supply and the base of the transistor should have a 330 ohm resistor in series from the output pin of the microcontroller.