5-Dodecanoylaminofluorescein

5-Dodecanoylaminofluorescein is an amphipathic (amphoteric) fluorescent probe (Ex/Em = 485 nm/515-535 nm), which consists of a hydrophilic fluorescein core and a hydrophobic dodecanoyl group (C12 fatty acid chain) linked by an amide bond. 5-Dodecanoylaminofluorescein is mainly used as an interface-localized radical trapping/indicator probe. Dodecanoylaminofluorescein can be used for the determination of the antioxidant properties of emulsions, or can serve as a lipophilic drug model for the study of passive skin penetration when encapsulated in tyrosine-derived nanospheres^[1][2][3]. In Vitro:5-Dodecanoylaminofluorescein (0.2-0.8 μM; 5 min-overnight) functions as a reliable, submicromolar-concentration fluorescent probe for detecting micelle formation via fluorescence anisotropy changes, enabling accurate critical micelle concentration measurements across nonionic, zwitterionic, anionic, and cationic detergents in varying buffer and ionic strength conditions, with consistent performance at concentrations from 0.2 μM to 0.8 μM^[1].
5-Dodecanoylaminofluorescein (180 μg/mL; 24 h) delivered via tyrosine-derived nanospheres shows 2 times more delivery to the superficial dermis and 2.5 times more to the lower dermis of full-thickness human cadaver abdominal skin than a propylene glycol formulation after 24 hours of topical application, with no detectable transdermal permeation^[2].
5-dodecanoylaminofluorescein (0.2 mg per 5 mL squalene; 1.5 h) serves as a valid probe for peroxyl radical activity in squalene W/O emulsions, showing that (+)-catechin-β-sitosterol preserves ~80% of its fluorescence intensity after 80 minutes at 60 °C, far outperforming control antioxidants and the no-antioxidant control^[3].

Guide (Below is the recommended solution we suggest. This solution is merely a guideline and should be modified according to your specific needs.)
Take the evaluation of peroxide free radical scavenging/antioxidation of W/O emulsion as an example^[3]
1. 5-Dodecanoylaminofluorescein stock solution: Weigh 5-Dodecanoylaminofluorescein, dissolve it with a small amount of methanol for assistance, then dry it with nitrogen gas, and dissolve it with an appropriate amount of anhydrous squalene to prepare the stock solution (~0.2 mg/mL), and store it in a dark place.
2. Oil phase: Take 5 mL of squalene and add 0.5 mL of the 5-Dodecanoylaminofluorescein stock solution. Mix well (final concentration ~ 20 mmol/kg of the oil phase, can be adjusted as needed).
3. Add antioxidants: Take 0.7 mL of the above oil phase, add the antioxidant to be tested (no addition for the control), and mix well.
4. Preparation of W/O emulsion: Take 20 µL of 200 mM AAPH (HY-Y0525) (dissolved in 25 mM phosphate buffer at pH 7.0), add it to 1.2 mL of the above oil phase, vortex for 30 seconds + ultrasonic for 2 minutes, to form a stable W/O emulsion.
5. Detection: Take 200 µL of the emulsion and place it in a 96-well plate on the blackboard. Use an enzyme reader with Ex/Em = 485/515 nm. Read the data every 1 minute at 60°C for approximately 90 minutes. Evaluate the antioxidant activity by observing the fluorescence decay curve (the fluorescence decay is slower when the antioxidant is present).