Description
Product Usage Information
trFluor™ Europium Cryptate conjugated antibodies are ideal for protein-protein interaction assays, pair-based immunoassay technologies, or high-throughput screening where greater sensitivity and quantitative detection is needed. The long fluorescent decay time of Europium Cryptate results in improved signal to background over fluorescent dye conjugates. Methods utilizing Europium Cryptate conjugated antibodies include, but are not limited to, TR-FRET, where Europium Cryptate-labeled donor antibodies are paired with red fluorophore-labeled acceptor antibodies, such as Alexa Fluor ® 647 or APC. Please contact us if you require an acceptor antibody clone conjugated to a red dye at a custom concentration, a carrier-free formulation, or a more customized packaging solution. Note: Addition of potassium fluoride (KF) in the assay dilution buffer range of 40-400 mM is recommended for enhanced fluorescent signal. Optimal dilutions and working concentrations of both the conjugated antibodies and the KF should be determined by the end user.
Storage
Supplied in PBS (pH 7.2), less than 0.1% sodium azide, and 2 mg/mL BSA. Store at 4°C. Do not aliquot the antibody. Protect from light. Do not freeze.
Specificity / Sensitivity
G4S Linker (E7O2V) Rabbit Monoclonal Antibody (trFluor™ Europium Cryptate Conjugate) recognizes exogenously expressed levels of scFv-based CARs containing a G4S linker.
Species Reactivity: All Species Expected
Source / Purification
Monoclonal antibody is produced by immunizing animals with a synthetic peptide containing three Gly4Ser repeats.
Background
The poly-Glycine-Serine (G4S) linker is a type of flexible, unstructured synthetic peptide linker sequence often leveraged to connect the variable heavy (VH) domain and variable light (VL) domain of single-chain variable fragments (scFvs) and chimeric antigen receptors (CARs) that utilize an extracellular domain scFv for target antigen recognition. The linker itself consists of a core pentapeptide sequence, Gly-Gly-Gly-Gly-Ser, that is repeated and commonly found as either a 15-mer (G4S) or 20-mer (G4S) within scFv-based CARs and scFv fragments. The linker sequence length plays a role in controlling scFv stability and the noncovalent association between the VH and VL domains (1,2).
