Modified silica particles are provided. Aspects of the particles include an outer layer that is composed of organically-modified silica comprising a siloxane-linked hydrophilic group, such as a charged functional group or a polar neutral functional group. The modified silica particles can form the basis of a variety of chromatography support materials. Also provided are methods of preparing the subject particles. Aspects of the methods include contacting silica particles with water, an ionic fluoride and an organosilane reagent comprising a hydrophilic moiety to produce modified silica particles wherein the hydrophilic moiety of the organosilane reagent is incorporated into an outer layer of the silica particles. Chromatography supports and kits including the subject particles and methods of using the same are also provided.