Description

Alexa Fluor 568 NHS Ester is a bright, orange-red fluorescent dye reactive ester used for labeling primary amines in proteins, peptides, antibodies, and other biomolecules. This high-performance succinimidyl ester is critical for creating stable, fluorescent conjugates with minimal impact on the biological activity of the target molecule. It is an essential tool for researchers and developers in life sciences, diagnostic assay development, and fluorescence microscopy, enabling multiplexed detection and high-sensitivity imaging.

Application

• Antibody and Protein Labeling: Conjugation to monoclonal antibodies, streptavidin, and other proteins for flow cytometry (FACS), immunohistochemistry (IHC), and immunofluorescence (IF).
• Peptide Tagging: Fluorescent labeling of synthetic peptides for cellular uptake studies and receptor binding assays.
• Microarray and Diagnostic Assays: Development of fluorescent probes for in-situ hybridization (FISH) and high-throughput screening platforms.
• Super-Resolution and Confocal Microscopy: Preparation of bright, photostable labels for advanced cellular and tissue imaging techniques.
• Biomaterial and Nanoparticle Functionalization: Covalent attachment to amine-modified surfaces, polymers, and nanoparticles for tracking and targeting applications.
• Bioconjugation for Drug Discovery: Creating fluorescently tagged small molecules or ligands for target engagement and pharmacokinetic studies.

Basic Information

Product Name	Alexa Fluor 568 NHS Ester
CAS No.	247145-38-6
Molecular Formula	C~38~H~41~N~3~O~13~S~2~
Molecular Weight	811.87 g/mol
Synonyms	Alexa Fluor® 568 NHS Ester; Alexa Fluor 568 Succinimidyl Ester; 5-(and-6)-(((N-(5-(and-6)-Carboxypentyl))-N-(5-((2,5-dioxo-1-pyrrolidinyl)oxy)-1,5-dioxopentyl))amino)sulfonyl)-2,7-dichlorofluorescein, Mixed Isomers; AF568 NHS Ester; Alexa568-SE; C41H41N3O13S2 (Parent Acid)
EINECS	Contact for details

Quality Control

Every batch of Alexa Fluor 568 NHS Ester is manufactured and tested to ensure the highest standards of purity and performance for sensitive bioconjugation applications. Our rigorous quality control includes comprehensive analytical characterization to confirm identity, purity, and functional reactivity. A detailed Certificate of Analysis (COA) is provided with each shipment, documenting key specifications such as HPLC purity, degree of labeling (DOL) efficiency, and absorbance/fluorescence profiles.

Storage

Preserve in a tightly closed container, protected from light. Store desiccated at -20°C or below. This product is hygroscopic (moisture-sensitive) and light-sensitive. Upon receipt, store the product immediately in a freezer. Allow the vial to equilibrate to room temperature in a desiccator before opening to prevent condensation and hydrolysis. For long-term storage, keep under an inert atmosphere.

Specification

Item	Specification
Appearance	Orange to red powder or solid
Identification (HPLC/MS)	Conforms to structure
Purity (HPLC)	≥ 90%
Absorption Maximum (λmax)	578 - 582 nm
Emission Maximum	599 - 603 nm
Extinction Coefficient (ε)	~91,000 cm⁻¹M⁻¹
Solubility	Soluble in DMSO, DMF, anhydrous DMSO
Functional Performance	Conforms to reference in standard labeling assay

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