Accessory Reagents

Bangs Bead Coupling Buffers are ready-to-use buffers that are available in a variety of pH levels (4.5 to 9.0). They can be used as coupling or wash buffers for plain, dyed, or functionalized polymer microspheres. Our Bangs Bead Storage Buffer is available in two pH levels: 7.4 and 8.5.

Our Bead Solution is a ready-to-use aqueous suspending solution for the dilution and/or storage of your uncoated plain, dyed, or functionalized polymer microspheres (both carboxylated or aminated). An antimicrobial agent deters microbial contamination, and stabilizers promote suspension dispersity, peace of mind, and harmonious accord in the laboratory. For general information, or to make your own, see our TSD 0300 Buffers.

Microspheres are routinely coated with ligands such as antibodies, oligonucleotides, and peptides, for use in diagnostics and bioseparations. Carboxyl- and amine-modified microspheres require the use of a chemical linker for activation and covalent immobilization of ligand. DEPC-Carbodiimide (EDAC) and Glutaraldehyde are two of the most common crosslinkers used in bead coating protocols. To purchase as a kit, see our coupling kits.

EDAC is a zero-length crosslinker that is routinely used for the covalent binding of amine-containing ligands to carboxylated microspheres.

Glutaraldehyde is a homobifunctional linker that is suitable for binding amine-containing ligands to amine-modified beads.

TRYPAN BLUE

REFERENCES

• Louis KS, Siegel AC. (2011) Cell viability analysis using trypan blue: manual and automated methods. Methods Mol Biol; 740:7-12.
• Phelan K, May KM.(2017) Mammalian Cell Tissue Culture Techniques. Curr Protoc Mol Biol.5;117:A.3F.1-A.3F.23

Surfactants are commonly utilized with microspheres composed of hydrophobic polymer matrices such as polystyrene to facilitate bead wetting and to deter or treat aggregation. Common concentrations are ~0.1% for uncoated polymer beads and ≤0.05% in the storage buffer of coated polymer, magnetic, and silica beads.

Triton™ X-100 and Tween^® 20 are nonionic surfactants used in the storage buffers of coated bead suspensions, while Sodium Dodecyl Sulfate (SDS) is an anionic surfactant that decreases hydrophobicity and participates in charge stabilization of the suspension.