A nanodevice mediated targeted delivery of drug and specific photokilling of cancer cells through ROS generation

A prototype nanodevice involving a Quantum dot (QD), a Photosensitizer (PS) and DNA for the targeted delivery of the PS drug is reported. The DNA mediated assembly of the ZnSe/ZnS QD–protoporphyrin IX (PpIX)–Mucin 1(MUC1) aptamer conjugate for targeting the MUC1 cancer biomarker is reported here for the first time. The photosensitizer, protoporphyrin IX (PpIX), was conjugated to a single stranded DNA and self-assembled to a complementary strand that was conjugated to a QD and harboring a MUC1 aptamer sequence. A multistep fluorescence resonance energy transfer (FRET) is shown that involves the QD, PpIX and covalently linked CFt 633 amine dye (CF dye) to the MUC1 peptide that tracks the potency of the aptamer to attach itself with the MUC1 peptide. The selective photodamage of MUC1 expressing HeLa cervical cancer cells through ROS generation in the presence of the QD–PpIX FRET probe upon irradiation is successfully demonstrated. This research finding is reported in the RSC journal “Integrative Biology” (DOI: 10.1039/c6ib00092d) and involves collaboration of Department of Chemistry, IIT Patna (Dr. Prolay Das & Dr. Sahid Hussain) with BARC, Mumbai and NIPER, Hajipur.