Figure 2.
Representative transmission electron microscopy (TEM) images of discrete nanostructures formed by the assembly of pure drugs. (A) Cui and coworkers demonstrated how folic acid could be induced to form nanofilamentous nanostructures by the addition of water to a solution in MeOH. Adapted with permission from ref [43], copyright 2013 Royal Society of Chemistry. (B) Hao characterized helical nanoribbons formed by camptothecin. Adapted with permission from ref [45], copyright 2014 Royal Society of Chemistry. (C–D) Yan and coworkers developed an irinotecan-chlorambacil (Ir-Cb) drug–drug conjugate (C) that could assemble into nanoparticles (D). Adapted with permission from ref [46], copyright 2014 American Chemical Society.