Disclosed herein are novel lipids and liposomal compositions prepared using such compounds and related methods of neutralizing or otherwise modifying such liposomal compositions. The lipids described herein are useful for example, as liposomal vehicles to facilitate the delivery of encapsulated polynucleotides to target cells and the subsequent transfection of such target cells. In certain embodiments, one or more of the compounds that comprise the liposomal delivery vehicle may be neutralized or further modified such that the properties of the liposomal delivery vehicle are modified.