A Fluorescent Cocktail Strategy for Differentiating Tumor, Inflammation, and Normal Cells by Detecting mRNA and H₂O₂

Accurately distinguishing tumors from noncancerous inflammation and normal tissues is hugely significent for tumor diagnosis and therapy. However, tumor and inflammatory tissues have similar pathologic characteristics in their microenvironment, making differentiation very difficult. Here, a fluorescent cocktail nanoparticle capable of simultaneously detecting intracellular mRNA and H2O2 was designed to differentiate tumors from nontumor cells. To detect targeted mRNA in living cells, a DNA probe was generated using the fluorescence resonance energy transfer (FRET) principle. A pH-responsive amphiphilic polymer was synthesized to realize the transportation of the DNA probe. In addition, the polymer was conjugated with a coumarin-boronic acid ester (Cou-BE) H2O2 probe. According to the change in the fluorescence of Cou-BE, tumor and inflammatory cells could be distinguished from normal cells owing to their high concentration of H2O2. Because of the different concentrations of tumor-related mRNA in tumor and nontumor cells, the fluorescence intensity of the DNA probe-loaded nanoparticles inside tumor cells was different from that inside inflammatory cells. Therefore, our fluorescent cocktail strategy could discriminate simultaneously tumor, inflammation, and normal cells through the cooperative detection of intracellular mRNA and H2O2, which demonstrated potential application value in biomedical research and clinical diagnosis.