Biotin/Streptavidin

• Biotin
• Streptavidin

Enzyme Conjugates

• Alkaline Phosphatase (AP)
• Glucose Oxidase (GOx)
• Horseradish Peroxidase (HRP)

Fluorescent Dyes

• Alexa Fluor - 488, 555, 568, 594, 647, 700
• AMCA
• Atto – 390, 488, 565, 633, 700
• Cyanine Dye - Cy3, Cy5, Cy5.5
• DyLight^TM - 350, 405, 488, 550, 594, 633, 650, 680, 755, 800
• FITC
• FluoProbes 647H
• Rhodamine
• Texas Red

Fluorescent Proteins

• Allophycocyanin (APC)
• B-Phycoerythrin (BPE)
• R-Phycoerythrin (R-PE)
• PerCP
• R-Phycocyanin (RPC)

Tandem Dyes

• Allophycocyanin/Cy5.5
• Allophycocyanin/Cy7
• PE/Atto594
• PE/Cy5
• PE/Cy5.5
• PE/Cy7
• PE/Texas Red
• PerCP/Cy5.5

1. Buffers and Additives

   The presence of low molecular weight substances in commercially available antibodies impacts the efficiency of the labeling process. Common antibody additives such as BSA, glycine, and azide contain lysine residues. As the majority of labeling methods exploit the lysine residue, forming a strong bond between the lysine and conjugate, any primary amine containing additive will be conjugated during the labeling reaction.

2. Antibody Concentration and Purity

   For efficient labeling, we recommend an antibody be greater than 95% pure and at a concentration greater than 0.5 mg/ml. We do not recommend conjugating antibodies harvested from ascites fluid, crude serum, or hybridoma culture supernatant. These antibodies contain protein and cell culture nutrients (amino acids) that impact conjugation. If your antibody is provided in one of these formulations, we recommend a purification or concentration step to remove unwanted additives prior to antibody labeling.