We have observed that no matter how long we cook human total RNA in the presence of magnesium, we never get fragments smaller than about 100 bp. I'm not complaining, but I don't understand it. Does anyone have an explanation for this?
Thanks!
eab
P.S., Our readout has typically been bioanalyzer pico RNA analysis after a purification method that recovers small fragments (isopropanol precipitation, or SPRI with isopropanol in the binding buffer). The total mass of RNA recovered is usually consistent with the input. So it isn't just that we are losing the smaller fragments before we can detect them . . . .
Thanks!
eab
P.S., Our readout has typically been bioanalyzer pico RNA analysis after a purification method that recovers small fragments (isopropanol precipitation, or SPRI with isopropanol in the binding buffer). The total mass of RNA recovered is usually consistent with the input. So it isn't just that we are losing the smaller fragments before we can detect them . . . .