We have LifeGuard solution that is past its expiry date, but has no visual indications of being expired (no precipitates, not cloudy, etc). Has anyone attempted RNA extractions using expired LifeGuard? How were your results?
Given the generic composition of LifeGuard (very high denaturing solute concentrations) , I'd be very surprised if the expiry date actually means anything. Given its cost, I'd recommend using it!