The self-assembly of anticancer camptothecin-dipeptide nanotubes: a minimalistic and high drug loading approach to increased efficacy.

20-(S)-Camptothecin (CPT)-conjugated dipeptides are reported that preassemble into nanotubes with diameters ranging from 80-120 nm. These nanoassemblies maintain a high (∼47 %) drug loading and exhibit greater drug stability (i.e., resistance to lactone hydrolysis), and consequently greater efficacy against several human cancer cells (HT-29, A549, H460, and H23) in vitro compared with the clinically used prodrug irinotecan. A key and defining feature of this system is the use of the CPT-conjugated dipeptide as both the drug and precursor to the nanostructured carrier, which simplifies the overall fabrication process.