Fluorescein Maleimide

SKU Unit Size Price Qty
SP-1502-12 12 mg
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Fluorescein Maleimide is used to label free thiol groups with fluorescein.  This fluorescent label can be directly visualized or used as a specific tag that can be detected with anti-fluroescein antibodies. For labeling nucleic acids, thiols can be introduced into DNA, RNA, or oligonucleotides using the 5' EndTag™ or 3' EndTag™ nucleic acid labeling systems.


More Information
Unit Size 12 mg
Target for Labeling DNA, Oligonucleotides, PNA, Protein, RNA
Recommended Storage - 20°C to - 80 °C.
Molecular Weight 498.4
Chemical Formula C27H18N2O8
Maximum Emission 520 nm
Maximum Excitation 492 nm
Required Reactive Group Thiol Group
Tag/Group Incorporated Fluorescein
Safety Title WARNING: NA - www.P65Warnings.ca.gov



Technical Information

Fluorescein Maleimide is designed for fluoresceinating proteins, nucleic acids or other molecules containing one or more thiol groups. Molecules to be labeled with Fluorescein Maleimide require free thiol groups. In the case of proteins, Fluorescein Maleimide will react with exposed cysteine residues. Alternatively, free thiols may be generated by reducing disulfide bonds or by modifying other reactive groups such as primary amines with compounds like Traut's reagent (2-iminothiolane).

This fluorescent label can be directly detected or used as a hapten and detected with our high affinity antibody reagents. (Excitation maximum at 495 nm; emission maximum at 515 nm).

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