pH-responsive lyotropic liquid crystals and their potential therapeutic role in cancer treatment

A weak amphiphilic base, pyridinylmethyl linoleate, is blended with monolinolein, yielding mesophases with a pH-induced hexagonal-to-cubic transition at pH <= 5.5. We show the potential therapeutic role of this mesophase in treating cancerous tissues exploiting their more acidic pH compared to healthy tissues. In vitro release studies with doxorubicin on HT29 human colon cancer cells show a 10-fold faster release and 3-fold increased efficiency for killing cancer cells at pH 5.5 versus pH 7.4, demonstrating the potential of this strategy in cancer treatment.