Solubility without complete destruction of the solid state structure means that you need to obtain a colloid of the silicotitanate. The colloid particles need to be electrically charged to be stabilized in solution. In fact there are even some commercially available pure titania colloids (like TiBALDH or CaptiGel, see, for example, Nanoscale_2013_ 5_3330-36). They contain electrically charged TiO2 nanoparticles. The silicotitanates are, however, usually available as micro crystals, see

http://sti.srs.gov/fulltext/srtlwp2189/srtlwp2189.html

This means that even if you get a suspension in HNO3 (charging the particles positively via protonation) it will be precipitating relatively easily.