I have found you don't need a centrifuge, just a piece of string and some tape.
put cap on tip
put material into syringe
put plunger cap on (to keep it from coming out)
tie string around the syringe tip cap and tape it to keep it from coming loose
swing it around as fast as you can
if you have a small metal tube, you can put the string through it, then after starting to spin, pull the string through to shorten it as it is spinning and make it go faster.
Repeat a few times, and most, if not all of the bubbles are gone.
One thing to remember is you want to move all the material to the plunger, NOT TO THE TIP, as you will then expel the air through the tip as you press the plunger in.