Combining hydrophilic and hydrophobic environment sensitive dyes to detect a wide range of cellular polarity.

Sang Jun Park,Hwan Myung Kim,Jae Hyung Jo,Vinayak Juvekar

doi:10.1039/c9sc04859f

Sang Jun Park, Hwan Myung Kim + Show 2 more

Open Access

https://doi.org/10.1039/c9sc04859f

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Journal: Chemical Science	Publication Date: Jan 1, 2020
Citations: 52	License type: CC BY 3.0

Affiliation: Inha University Hospital, Ajou University

Abstract

Intracellular polarity is an important parameter of pathological and biological phenomena of cells; abnormal polarities are associated with diabetes, neurological diseases, and cancer. However, previously reported polarity probes have issues with quantitatively detecting intracellular polarities, can measure only a limited range of polarities, and can only detect specific intracellular regions. Here, we developed a novel two-dye system, RPS-1, that contains a new "turn-on" polarity probe (Dye1) based on a spiropyran intramolecular ring closing-opening system activated in polar protic solvents, and a benzothiadiazole containing dye (Dye3), which emits only in non-polar solvents with a large stoke shift. Individually, Dye1 and Dye3 selectively localized to lysosome and lipid droplets, respectively; however, combining these dyes, which have completely different characteristics, via a piperazine linker resulted in the staining of various intracellular organelles. Therefore, as Dye1 and Dye3 have the same absorption but different emissions, combining them resulted in a ratiometric polarity probe that could quantitatively measure a wider polarity range inside the cell using a single excitation source. In addition, ratiometric imaging using our RPS-1 probe to quantitatively detect the distribution of polarity in different cell lines indicated that lysosomes were the most polar organelles in the cell.

Highlights

Intracellular polarity is an important parameter of pathological and biological phenomena of cells; abnormal polarities are associated with diabetes, neurological diseases, and cancer
The pathological activity of the cell changes with its polarity, and abnormal polarity is related to diabetes, neurological diseases, and cancer.[8,9,10,11]
Polarity probes were synthesized by condensing salicylaldehyde and 1,2,3,3-tetramethyl-3H-indolium iodide under ethanol (EtOH) conditions

Summary

Introduction

Polarity, viscosity, temperature, redox status, and pH parameters are critical for the initiation and maintenance of the physical and chemical behaviors of biomolecules, because their distribution, spatial arrangement, and composition within the cell are heterogeneous.[1,2] Intracellular polarity, in particular, is key to various cellular processes such as cell proliferation, immune system regulation, increases in the number of local membranes, stimulation of cell migration, and vectorial transport of molecules across the cell layer.[3,4] Each organelle of the cell has an optimal polarity depending on its role and the polarity changes in real time as the intracellular environment changes.[5,6,7] The pathological activity of the cell changes with its polarity, and abnormal polarity is related to diabetes, neurological diseases, and cancer.[8,9,10,11] detecting cellular polarity is important in research on pathological and biological phenomena.The only way to observe intracellular polarity is to use optical imaging; various uorescent probes have been developed to detect the polarity of microenvironments.[12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27]. As Dye[1] and Dye[3] have the same absorption but different emissions, combining them resulted in a ratiometric polarity probe that could quantitatively measure a wider polarity range inside the cell using a single excitation source. Ratiometric imaging using our RPS-1 probe to quantitatively detect the distribution of polarity in different cell lines indicated that lysosomes were the most polar organelles in the cell.

Results

Conclusion