Herein presented are gold nanoparticles (AuNPs) used for the transport of medications to mucous membranes. The AuNPs are ultra-stable in that they withstand freeze-drying and heating treatments without noticeable change in their structure. In addition, they interact with mucous membranes, and therefore allow transport of certain drugs to these mucous membranes, allowing higher exposure time of the drugs, hence decreased dosing schedule of administration.