The study of mechanisms of nucleic acid transport across the cell membrane is valuable both for understanding the biological function of extracellular nucleic acids and the practical use of nucleic...

We describe herein a new method for cleaving from resin and removing acid-labile protecting groups in solid-phase peptide synthesis in the presence of a polyfluorinated alcohol (either trifluoroethanol, TFE, or hexafluoroisopropanol, HFIP). It was shown that 0.1 M HCl in hexafluoroisopropanol or trifluoroethanol removes the acid-labile protecting groups commonly used in Fmoc SPPS for the protection of amino acid side-chains, such as t-butyl ester and ether, Boc, trityl, and Pbf groups including the most acid-resistant -hydroxymethylphenoxyacetyl group (HMPA), -benzyloxy benzyl ester (Wang resin), Rink amide, and peptide amide linker (PAL). The addition of 5–10% of a hydrogen-bonding solvent was shown to considerably retard or even fully inhibit the reaction. However, nonhydrogen-bonding solvents, such as dichloromethane, do not slow down the reaction.