The differences between item 9532S-0PV and 9532S-MS is that item 9532S-MS is made from a special type of polypropylene and we do not use “mold release agents” in the molding process making it less likely to have any extractables or leachables under any circumstance. 

Acetonitrile is likely to remove existing mold release agents which can show up in chromatograms as spurious peaks.