AF488 NHS ester 

AF488 NHS ester is an amine specific fluorescence probe (Em=525 nm). AF488 NHS ester reacts with sulfhydryl groups and amines in aqueous and biological samples then change their chemical structure and fluorescence properties after derivatization^[1].

IgG fluorescent labeling and anti-IgG solid phase peptide libraries screening of AF488 NHS ester^[2]
(1) Dissolve the lyophilized immunoglobulin in a solution of 50 mM sodium phosphate, 20 mM sodium chloride and PH 8.3 at a concentration of 5 g/L.
(2) Dissolve 1 mg of AF488 NHS ester in 100 µL extra dry DMF, add 1 mL of solution in (1), and incubate at room temperature for 1 h.
(3) Collect samples with Amicon Ultra 0.5-mL Centrifugal Filter Unit equipped with 3-kDa MWCO filters.
(4) The deprotected libraries of hexameric or tetrameric are washed in 50 mM sodium phosphate, 150 mM sodium chloride, PH 7.4 (PBS) solution with 5× settled resin volume washing three times to balance.
(5) Dilute IgG-AF488 with 50 mM sodium phosphate, 150 mM sodium chloride, 0.2% Tween (PH 7.4) solution until the final concentration is 1.3 mg/mL.
(6) Incubate (4) and (5) at 2-8°C overnight.
(7) Wash resin beads with 50 mM sodium phosphate, 150 mM sodium chloride, 0.1% Tween 20, PH 7.4 (PBS-T).
(8) The resin is deposited in a 96-well plate of 40 µL PBS-T with one bead per well, and then the fluorescence microscope is used to image at 10× magnification. Under 480 nm excitation, Alexa Fluor 488 fluorescence measurement and fluorescence screening are carried out with 510 nm emission intensity as the threshold.
AF488 NHS ester storage solution^[1]
Prepare 20 mM AF488 NHS ester with DMF.
Note: AF488 NHS ester storage solution is recommended to be stored in dark at -20°C after sub-packaging.

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

631.54

C₂₅H₁₇N₃O₁₃S₂

1374019-99-4

Solid

Yellow to orange

O=C(C1=C(C2=C(C=CC(N)=C3S(=O)(O)=O)C3=[O+]C4=C2C=CC(N)=C4S(=O)([O-])=O)C=CC(C(ON5C(CCC5=O)=O)=O)=C1)O

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Kendall CG, et al. Amine Analysis Using AlexaFluor 488 Succinimidyl Ester and Capillary Electrophoresis with Laser-Induced Fluorescence. J Anal Methods Chem. 2015;2015:368362.  [Content Brief]

  [2]. Lavoie RA, et al. Targeted Capture of Chinese Hamster Ovary Host Cell Proteins: Peptide Ligand Discovery. Int J Mol Sci. 2019 Apr 8;20(7):1729.  [Content Brief]