TABLE 6.

Effect of salt type on virus adsorption to Millipore HA filters at pH 7

Virus	% Viral adsorptionc
	Bufferb	Buffer containing 0.1 M MgCl2	Buffer containing 0.3 M NaCl
MS2	8 A	99 B	61 C
PRD-1	6 A	59 B	3 C
φX174	4 A	57 B	42 B
Poliovirus 1	3 A	99 B	>99 B
Mean	5	79	51

^aExperiments were performed as described in Table 1, footnote a, except that the ionic strength of the salts was maintained at 0.3. 

^bValues from Table 1. 

^cValues on the same line followed by the same letter are not significantly different at P = 0.05.