Description

3',6'-Bis(Dimethylamino)-3-Oxospiro[Isobenzofuran-1(3H),9'-[9H]Xanthene]-6-Carboxylic Acid 2,5-Dioxo-1-Pyrrolidinyl Ester is a reactive, activated ester derivative of the widely used fluorescent dye, Rhodamine B. This compound is a critical intermediate for the synthesis of advanced fluorescent probes, labels, and conjugates used in life science research and diagnostics. It is primarily sought by manufacturers and researchers in the biotechnology, pharmaceutical, and diagnostic reagent industries for creating highly sensitive detection systems.

Application

• Fluorescent Labeling Reagent: Used to covalently label proteins, antibodies, peptides, and nucleic acids for fluorescence microscopy, flow cytometry, and immunoassays.
• Bioconjugation Intermediate: Serves as a key building block for synthesizing custom fluorescent dyes and probes with specific targeting moieties.
• Diagnostic Kit Manufacturing: Incorporated into lateral flow assays, ELISA kits, and other in-vitro diagnostic (IVD) products as a signal-generating component.
• Cell Biology Research: Enables the tracking and visualization of cellular processes, receptor binding, and intracellular trafficking.
• Material Science Marker: Used to functionalize nanoparticles, polymers, and other materials for traceability and imaging purposes.
• Chemical Sensor Development: Acts as the fluorophore core in the design of chemosensors for detecting ions, small molecules, or pH changes.

Basic Information

Product Name	3',6'-Bis(Dimethylamino)-3-Oxospiro[Isobenzofuran-1(3H),9'-[9H]Xanthene]-6-Carboxylic Acid 2,5-Dioxo-1-Pyrrolidinyl Ester
CAS No.	1027512-41-9
Molecular Formula	C33H30N3O7
Molecular Weight	580.61 g/mol
Synonyms	Rhodamine B NHS Ester; Rhodamine B Succinimidyl Ester; 5(6)-Carboxy-rhodamine B NHS ester; X-Rhodamine NHS Ester; Rhodamine B N-Hydroxysuccinimide Ester; Sulforhodamine B NHS Ester (common misnomer); 3',6'-Bis(diethylamino)spiro[isoindole-1,9'-xanthene]-3-one-6-carboxylic acid, 2,5-dioxopyrrolidin-1-yl ester (alternative IUPAC); RB-NHS
EINECS	Contact for details

Quality Control

Our production of this high-value biochemical intermediate adheres to stringent quality protocols to ensure batch-to-batch consistency and optimal performance in sensitive applications. Each lot is characterized by HPLC for purity and identity, with typical purity grades exceeding 95%. A comprehensive Certificate of Analysis (COA) detailing assay, impurity profile, and functional performance data is provided with every shipment.

Storage

Preserve in a tightly closed container, protected from light. Store desiccated at -20°C or below for long-term stability. This compound is hygroscopic (moisture-sensitive) and light-sensitive. Allow the sealed vial to equilibrate to room temperature before opening to minimize moisture condensation.

Specification

Item	Specification
Appearance	Dark red to purple solid
Identification (IR)	Conforms to structure
Purity (HPLC)	≥ 95.0%
Water Content (KF)	≤ 1.0%
Solubility	Soluble in DMF, DMSO, acetonitrile
Functional Test (Labeling)	Conforms to reference

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.