DXB-NIR

Guidelines (The following is a recommended experimental protocol for guidance only, and adjustments are required based on your specific needs)

1. Stock Solution Preparation
1.1 Solvent: For most dyes, organic solvents such as anhydrous DMSO are commonly used for dissolution.
1.2 Concentration Recommendation: Prepare a high-concentration stock solution at 1-10 mM.

2. Working Solution Preparation
2.1 Diluent: Serum-free medium or PBS is typically used. Proteins and esterases in serum may interfere with staining results or cause dye hydrolysis.
2.2 Working Concentration: 100-200 nM.
2.3 Notes: Adjust the working solution concentration as needed; prepare fresh before use.

3. Staining Procedure
3.1 Sample Type Description
3.1.1 Adherent cells^[1][2]: HeLa cells and A549 cells.
3.2 Incubation Conditions
3.2.1 Incubate with DXB-NIR in OptiMEM at 20°C for 30 min.
3.3 Washing

5. Detection and Analysis
5.1 Instrument Type: Fluorescence microscope (spinning disk confocal, wide-field, two-photon or laser confocal microscope).
5.2 Excitation/Emission Wavelengths
5.2.1 Single-photon imaging: Excitation wavelength is 550 nm; emitted light is split into a far-red channel (<640 nm) and a near-infrared (NIR) channel (>640 nm).
5.2.2 Two-photon imaging: Excitation wavelength is 930 nm; emitted light is split into a far-red channel (<640 nm) and a near-infrared (NIR) channel (>640 nm).
5.3 Result Analysis
5.3.1 Changes in fluorescence intensity: Under stress conditions (cholesterol depletion, starvation, oxidative stress), increased intensity in the near-infrared (NIR) channel (>640 nm) indicates enhanced local polarity of lipid compartments; fluorescence changes corresponding to polarity changes of lipid droplets under nutrient deficiency and oxidative stress conditions can be detected.
5.3.2 Fluorescence localization: Localizes to the plasma membrane, endoplasmic reticulum and lipid droplets in live cells.
5.3.3 Color changes: Shows far-red color (<640 nm, pseudocolored green) in low-polarity environments (such as liquid-ordered membrane phases, plasma membrane); shows near-infrared color (>640 nm, pseudocolored red) in high-polarity environments (such as liquid-disordered membrane phases, stressed lipid compartments).
5.3.4 Ratio analysis: Calculate the intensity ratio of the near-infrared (NIR) channel to the far-red channel (I (>640)/I (<640)) to quantify polarity differences among different cellular compartments and under different stress conditions.

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.