BTC1070

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: Most dyes are usually dissolved in organic solvents, such as anhydrous DMSO.
1.2 Concentration Recommendation: It is recommended to prepare a high-concentration stock solution of 1-10 mM.

2. Working Solution Preparation
2.1 Diluent: PBS (pH 7.4).
2.2 Working Concentration: 5-10 μM; 1.25 nmol/50 μL (for intradermal injection).
2.3 Notes: Adjust the working solution concentration as needed; prepare and use immediately.

3. Staining Procedures
3.1 Sample Type Description
3.1.1 For studies on the lymphatic system and gastric tissue of living mice^[1]:
3.1.2 For studies on living mouse samples^[2]:
3.2 Incubation Conditions
3.2.1 For in vivo lymphatic imaging^[1]: Intradermally inject 50 μL of the working solution into the dorsal skin of the mouse's hind paw, and perform imaging 60 min after injection.
3.2.2 For in vivo gastric pH imaging^[1]: First administer simulated gastric juice to mice by gavage, then orally administer 20 μL of the stock solution at a concentration of 500 μM, followed by imaging under anesthesia.
3.2.3 For studies on living mouse samples^[2]: Use an 808 nm laser for excitation.
3.3 Washing Steps
3.3.1 No washing step is specified for in vivo applications.

4. Control Setup
4.1 Use IR26 and indocyanine green (ICG) as control fluorophores for in vivo lymphatic imaging and photostability studies.

5. Detection and Analysis
5.1 Instrument Type: NIR-II fluorescence imaging system equipped with an InGaAs camera; NIR-II fluorescence imager.
5.2 Excitation/Emission Wavelengths
5.2.1 Excitation Wavelength: 808 nm (for pH-responsive imaging, ratiometric detection and studies on living mouse samples); 1064 nm (for lymphatic imaging and photostability studies).
5.2.2 Emission Wavelength: 900-1700 nm; 1000-1700 nm; 1200-1700 nm; 900-1300 nm; 1000-1300 nm.
5.2.3 Spectral Characteristics: Maximum absorption wavelength: 1014 nm in dichloromethane, 1015 nm in aqueous solution; maximum fluorescence emission wavelength: 1070 nm in dichloromethane, 1065 nm in aqueous solution.
5.3 Result Analysis
5.3.1 Lymphatic Imaging Results: Lymphatic vessels and lymph nodes can be visualized clearly with high contrast, with minimal signal attenuation at a tissue depth of up to 8 mm.
5.3.2 Photostability Study Results: Approximately 70% of the fluorescence signal remains after continuous irradiation with a 1064 nm laser for 60 min.
5.3.3 pH-Responsive Imaging Results: Within the pH range of 1-4, the ratiometric fluorescence signal changes (F_1000-1300/F_900-1300 or F1000LP/F900LP), and the emission peak shifts from 1065 nm to 980 nm; the lower the pH value, the smaller the ratio value, the higher the fluorescence intensity, and the blue shift of the emission peak occurs.
5.3.4 In Vivo Gastric pH Sensing Results: The ratiometric signal is accurately correlated with gastric pH value, with a difference ≤0.27 pH units compared with the value measured by a standard pH meter; the stomachs of mice under different pH environments show clear outlines with significant pseudocolor differences.

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