The surface properties of nanoparticles play an important role in their interactions with their surroundings. Silane reagents have been used for surface modifications to silica shells on iron oxide nanoparticles, but using these reagents presents some challenges. An alternative approach to modifying the surfaces of these silica shells was developed to impart different terminal functional groups, such as a thiol, alcohol, or carboxylic acid, through the use of alcohol-based reagents. This approach to surface functionalization of the core-shell particles was verified through chemical analyses and the attachment of gold nanoparticles. The use of the silanol-alcohol condensation reaction could be extended further to other surface functionalizations through the use of additional alcohol-based reagents.