Nano-CaCO₃ as a pH sensitive theranostic platform

Theranostic platforms allow the capability of both diagnostic level imaging and therapy for diseases such as cancer. The decreased pH found in the extracellular environment in cancer is an ideal target for cancer theranostics, because it is both a unique and universal hallmark that distinguishes tumor regions from normal tissue, but also that the decreased pH has been linked to tumor growth and metastasis. We describe herein the development of nano-CaCO₃, a novel nanoparticle that can both increase pH in vivo resulting in therapeutic benefit, but also dissolves only at pHs less than 7.4 in vivo, creating a pH sensitivity to the nanoparticle that can be used to detect the more acidic pH ranges in vivo. As a result, nano-CaCO₃ is pH sensitive theranostic platform for cancer detection and treatment in vivo.