Upon purchase of MISSION® esiRNA, the esiRNA will reduce target mRNA levels by 70% or greater, in cultured cells, when transfected at 30 nM or greater. If the esiRNA do not knockdown the target gene by 70%, Sigma® will provide an additional esiRNA for that target gene free of charge. In the case that there are no more esiRNA for that gene target, Sigma will refund the price of the target MISSION esiRNA. Receipt of appropriate supporting data for transfection efficiency is required for the guarantee. Appropriate supporting data for transfection efficiency would include quantitative PCR based silencing data, comparing target mRNA levels of a Validated MISSION esiRNA, transfected at 30 nM or greater, to an appropriate negative control (such as mock transfection, RLUC, FLUC, or eGFP MISSION esiRNAs), demonstrating knockdown of the target mRNA greater than or equal to 70%. Due to the variability of antibodies and protein half-lives, we are unable to accept protein based detection methods.