In accordance with the disclosure, a method of forming a nanochannel is provided. The method includes depositing a photosensitive film stack over a substrate; forming a pattern on the film stack using interferometric lithography; depositing a plurality of silica nanoparticles to form a structure over the pattern; removing the pattern while retaining the structure formed by the plurality of silica nanoparticles, wherein the structure comprises one or more enclosed nanochannels, wherein each of the one or more nanochannels comprise one or more sidewalls and a roof; and partially sealing the roof of one or more nanochannels, wherein the roof comprises no more than one unsealed nanochannel per squared micron.