A DNA Tetrahedron Nanoprobe with Controlled Distance of Dyes for Multiple Detection in Living Cells and in Vivo

Multicomponent quantitative detection in living samples is becoming increasingly important; however, the current detection strategy may cause fluorescence self-quenching and reduce the sensitivity of detection. To solve the problem, we develop a DNA tetrahedral nanoprobe to control the dyes distance for simultaneous detection of multiple analytes. Compared to mesoporous silica nanoparticles based nanoprobes, the DNA tetrahedral nanoprobes display enhanced fluorescence intensities due to partially avoiding the fluorescence resonance energy transfer. Confocal fluorescence images show that the nanoprobes are capable of detecting and visualizing pH and O2•– in living cells under a single wavelength excitation. In an inflammation model for mice, the nanoprobes simultaneously image the down-regulation of pH and up-regulation of O2•–. We expect that the current strategy can provide new opportunities in designing probes for multiplexed detection with reduced self-quenching and enhanced sensitivity.