Caffeine orange

Guidelines (The recommended experimental protocol below is for guidance only and needs to be adjusted according to your specific requirements)^[1]

1. Stock Solution Preparation
1.1 Solvent: Water.
1.2 Recommended concentration: 1 mM.

2. Working Solution Preparation
2.1 Diluent: Water.
2.2 Working concentration: 10 μM.
2.3 Notes: Adjust the working solution concentration as needed; prepare and use immediately.

3. Staining Procedure
3.1 Sample type: Liquid media (beverage samples such as coffee, soft drinks, etc.).
3.2 Incubation condition: Incubate with 10 μM Caffeine Orange working solution.
3.3 Washing steps:
3.3.1 Solid Phase Extraction (SPE) column operation: First rinse the SPE column with 75% aqueous ethanol solution, then wash sequentially with 1 mM K₂CO₃ solution and water, and finally elute 1,3,7-trimethylxanthine with 15% aqueous ethanol solution.

4. Detection and Analysis
4.1 Instruments: Fluorescence reader, fluorometer, fluorescence spectrometer, or visual analysis with a light source.
4.1.1 Excitation wavelength: ~530 nm; ~532 nm.
4.2 Result analysis:
4.2.1 Fluorescence intensity change: In the presence of 20 mM 1,3,7-trimethylxanthine, the fluorescence intensity increases by up to 66-fold.
4.2.2 Color change: Under irradiation with a 532 nm light source, orange fluorescence indicates the presence of 1,3,7-trimethylxanthine; green fluorescence indicates the absence of 1,3,7-trimethylxanthine.

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