| Abstract: | Eight lots of reagent-grade phenol from four companies were tested for capacity to interact with Cu2+ to produce an inactivator or inactivators of the transfective RNA obtained from poliovirions; such capacity to interact with Cu2+ is referred to as cofactor activity. Six of the lots showed cofactor activity; two did not. A review of the data on the phenol lots and of the properties of the impurity or impurities conferring cofactor activity suggested that the active impurity(ies) might be a dihydric or trihydric phenol. Commercial catechol, resorcinol, hydroquinone, orcinol and pyrogallol were tested and found active. The activity of hydroquinone was outstandingly high. Upon serial recrystallization, the activity of catechol, hydroquinone, orcinol and pyrogallol remained constant, but the activity of resorcinol decreased markedly, in stepwise fashion, showing the most of the activity of the commercial resorcinol was due to impurity(ies). Each of catechol, hydroquinone, orcinol, pyrogallol, and the commercial resorcinol was shown to react with Cu2+ to produce inactivator(s). The effective target for inactivator(s) was the RNA and not the transfection process. The kinetics of inactivator(s) production varied for the different phenols, and the inactivator activity of the incubated mixture of pyrogallol and Cu2+ was notably labile. |
