Description

Caged Fluorescein Maleimide* CAS NO 167776-24-1 is a specialized, photoactivatable fluorescent labeling reagent designed for advanced bioconjugation and imaging applications. This compound matters because it enables precise, spatiotemporal control over the labeling of thiol groups in proteins, peptides, and other biomolecules, a critical capability for dynamic studies in live cells. Researchers and developers in the fields of biochemistry, cell biology, and pharmaceutical discovery rely on this high-purity reagent for techniques such as fluorescence resonance energy transfer (FRET), super-resolution microscopy, and the study of protein dynamics and interactions.

Application

• Site-specific protein labeling for structural and functional studies via cysteine thiol conjugation.
• Live-cell imaging and tracking, enabling the controlled activation of fluorescence to monitor biological processes in real time.
• Fluorescence Resonance Energy Transfer (FRET) assays to investigate protein-protein interactions and conformational changes.
• Super-resolution microscopy techniques (e.g., PALM, STORM) that require photoactivatable fluorophores.
• Development of diagnostic probes and biosensors with activatable fluorescence signals.
• Bioconjugation for antibody-drug conjugates (ADCs) and other therapeutic biomolecule modifications.
• Study of intracellular trafficking and organelle dynamics using caged fluorescence for precise timing.

Basic Information

Product Name	Caged Fluorescein Maleimide*
CAS No.	167776-24-1
Molecular Formula	C27H18N2O8
Molecular Weight	498.44 g/mol
Synonyms	5-((2-((2,5-Dioxo-2,5-dihydro-1H-pyrrol-1-yl)methyl)-4-nitrophenoxy)methyl)-2-(3-hydroxy-6-oxoxanthen-9-yl)benzoic Acid; 6-(2-((2,5-Dioxopyrrolidin-1-yl)methyl)-5-nitrophenoxy)-3-oxo-3H-xanthen-9-yl)benzoic Acid; Fluorescein Maleimide, Caged; 5-FAM Maleimide, Caged; Photoactivatable Fluorescein Maleimide; 1-(2-((9-(2-Carboxy-5-((3-hydroxy-6-oxo-6H-xanthen-9-yl)methyl)phenoxy)methyl)-5-nitrophenyl)methyl)-1H-pyrrole-2,5-dione
EINECS	Contact for details

Quality Control

Our Caged Fluorescein Maleimide is manufactured under strict quality control protocols to ensure batch-to-batch consistency and high performance. Each lot undergoes rigorous analytical testing, including HPLC for purity verification and spectroscopic analysis for identity confirmation, to meet the exacting standards required for life science research. A comprehensive Certificate of Analysis (COA) detailing purity, identity, and performance characteristics is provided with every shipment.

Storage

Preserve in a tightly closed container, protected from light. Store at -20°C or below in a desiccated environment. This product is hygroscopic (moisture-sensitive) and light-sensitive. Allow the vial to equilibrate to room temperature in a desiccator before opening to minimize moisture uptake.

Specification

Item	Specification
Appearance	Orange to red powder
Identification (HPLC)	Conforms
Identification (NMR)	Conforms
Purity (HPLC)	≥ 95%
Extinction Coefficient	Contact for details
Photoactivation Wavelength	~360-400 nm
Emission Wavelength	~515-520 nm
Solubility	DMSO, DMF
Water Content (KF)	< 1.0%

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