Intracellular Messenger RNA Triggered Catalytic Hairpin Assembly for Fluorescence Imaging Guided Photothermal Therapy.

We show a theranostic nanoplatform for messenger RNA (mRNA) triggered enhanced fluorescence imaging guided therapy. Catalytic hairpin assembly (CHA) and gold nanorods (AuNRs) are employed to fabricate the theranostic nanoplatform. Two hairpin DNAs and Cy5 labeled duplex DNA are integrated into the CHA for mRNA triggered fluorescence signal amplification via hybridization and displacement with mRNA. The AuNRs act both as the fluorescence quencher and the photothermal therapy (PTT) agent. The nanoplatform not only enables sensitive and specific imaging of target mRNA in living cells and good differentiating of the survivin mRNA expression levels in different cell lines but also offers excellent photothermal conversion efficiency for PTT. The developed nanoplatform has great potential for sensitive and specific intracellular mRNA imaging guided PTT.