DNA Triplex and Quadruplex Assembled Nanosensors for Correlating K⁺ and pH in Lysosomes

Abstract

It remains an unanswered question whether the flux of K + and H + in lysosomes are correlated due to difficulties in simultaneously imaging these two ions.This question is of great value for understanding lysosomal acidification. Herein, we designed DNAq uadruplex and triplex based luminescent nanosensors that can, respectively monitor K + and pH in lysosomal lumen. Eachs ensor contained an upconversion nanoparticle luminophore and ag old nanoparticle quencher, producing green and blue luminescence signals for K + and H + , respectively.T he sensors were tested in buffers showing dynamic ranges of 5t o2 00 mM K + and pH 5.0 to 8.2. Coimaging using these two sensors in cells indicated that the influx of H + was accompanied with the efflux of K + ,solving this longstanding question of the lysosomal biochemistry.

Near‐Infrared Light‐Activatable Spherical Nucleic Acids for Conditional Control of Protein Activity

“…Recently, upconversion nanoparticles (UCNPs), which can absorb NIR light and convert it into UV and visible emissions, have been employed as a light-transducer for activating photoresponsive systems with NIR light. [20][21][22][23][24][25][26] For example, the integration of UCNPs with functional DNA was designed to achieve NIR light-controlled biosensing and therapeutics. [20][21][22]25] Very recently, Liu and McHugh et al reported the design of UCNPs-mediated, NIR lightcontrolled regulation of ChR2 protein and thus neuronal activity.…”

Spatiotemporally Selective Molecular Imaging via Upconversion Luminescence‐Controlled, DNA‐Based Biosensor Technology

“…[16,17,[21][22][23][24] In particular, UCNPs have been combined with DNA-based components to construct biosensors for the detection and imaging of various analytes. [25][26][27][28][29][30] In these designs, acceptors were carefully selected and modified on the surface of UCNPs (as the donor) for the construction of Förster resonance energy transfer (FRET)-based sensors, in which the target detection is based on the changes in UCL intensity. [25] In this Minireview, we summarize the development of UCL-controlled, DNA-based sensor technologies for spatiotemporally selective molecular imaging (Figure 1).…”