Vector Labs is closed to observe Juneteenth (US Holiday) on Wednesday, June 19th.
We will be back in the office on Thursday. We will respond to emails upon our return. Have a wonderful day.

Texas Red™ Maleimide (SP-1505-3.6)

The product has been discontinued

Please contact Technical Support @ [email protected] for assistance in finding alternative.

The product has been discontinued

We have discontinued this product permanently. Please find alternative products from below section:

5′ EndTag™ Nucleic Acid Labeling Kit (MB-9001)

3′ EndTag™ DNA End Labeling System (MB-9002)

Biotin (Long Arm) Maleimide (SP-1501-12)


Texas Red Maleimide can be used to label free thiol groups with this high quantum yield rhodamine derivative. This tag can either be directly visualized or detected using anti-rhodamine antibodies. Texas Red Maleimide is designed for fluorescent labeling of proteins, nucleic acids or other molecules containing one or more thiol groups.


Unit Size3.6 mg
Target for LabelingDNA, Oligonucleotides, PNA, Protein, RNA
Recommended Storage– 20°C to – 80 °C.
Molecular Weight728
Chemical FormulaC37H36N4O8S2
Maximum Emission614nm
Maximum Excitation592nm
Required Reactive GroupThiol Group
Tag/Group IncorporatedTexas Red
Safety TitleWARNING: NA –


Technical Information

Molecules to be labeled with Texas Red Maleimide require free thiol groups. In the case of proteins, Texas Red 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).

For labeling nucleic acids, thiols can be introduced into DNA, RNA, or oligonucleotides using the 5′ EndTag™ or 3′ EndTag™ nucleic acid labeling systems.

This fluorescent label is a high quantum yield rhodamine derivative that can be directly visualized. The label can also be detected, and the signal amplified, using our affinity-purified antibody conjugates to rhodamine. (Excitation maximum at 595 nm; emission maximum at 615 nm).

Applicable patents and legal notices are available at legal notices.