Separation of SV40 from Poliovirus by Extraction with 1-Butanol

Summary Poliovirus and SV40 in tissue culture fluids are neither removed nor inactivated by extraction with diethyl ether, chloroform or fluorocarbon. However, similar treatment with 1-butanol removes large amounts of SV40 from aqueous suspensions. The infectious titer of poliovirus is practically unaffected by the same procedure. That the action of 1-butanol on SV40 is one of extraction into the solvent phase rather than virus inactivation has been demonstrated in two ways. First, an addition of 1-butanol sufficient to saturate the aqueous suspension did not reduce the infectious titer significantly. Second, the virus was recovered quantitatively from an emulsion of equal volumes of 1-butanol and virus fluid. However, when the aqueous and solvent phases were separated, the titer in the aqueous layer was reduced by at least 4 logs (base 10). Extraction of samples of rejected Sabin polio vaccine/high in adventitious SV4Q, with an equal volume of 1-butanol and subsequent Seitz filtration reduced the concentration of the contaminating virus to a very low level. The infectious titer of 11 viruses, other than polio and SV40, was reduced on extraction with 1-butanol. It has not been determined whether the effect on these viruses was due to inactivation or removal from the aqueous layer.