Intended use
Dynabeads Streptavidin are well-suited for numerous applications, including purification of proteins, nucleic acids purification, protein interaction studies, immunoprecipitation, immunoassays, phage display, biopanning, drug screening and cell isolation.
Guidelines for use
All Dynabeads Streptavidin can be used with biotinylated molecules. Some beads are more suitable for particular applications due to their characteristics. Dynabeads M-280 Streptavidin and Dynabeads MyOne Streptavidin T1 are commonly used for protein and nucleic acids applications. Dynabeads M-270 Streptavidin and Dynabeads MyOne Streptavidin C1 are preferred for nucleic acid diagnostics, specifically with samples with a high chaotropic salt concentration, immunoassays involving small biotinylated antigens and applications that are not compatible with BSA (these beads are not blocked with BSA). MyOne Dynabeads offer increased binding capacity and slower sedimentation rate, making them exceptional for automated applications and for when larger amounts of biotinylated ligand, or their specific target, need to be isolated.
Description of materials
Dynabeads Streptavidin are uniform, superparamagnetic beads with a streptavidin monolayer covalently coupled to the surface. This layer helps ensure negligible streptavidin leakage while the lack of excess adsorbed streptavidin helps ensure batch consistency and reproducibility of results. These beads give easy and stable binding of biotinylated molecules such as small molecules, peptides, proteins, antibodies, sugars, lectins, oligonucleotides, DNA/RNA etc.
Materials supplied
Table 1. Materials supplied in the Dynabeads Streptavidin Trial Kit. Sodium azide (NaN
3) is used as a preservative. Abbreviations: Volume (V) Phosphate buffered saline (PBS)
Dynabeads | V [ml] | Concentration [mg/ml] | Supplied in | Bead diameter [μm] |
---|
M-280 Streptavidin | 1 | 10 6-7x108 beads/ml) | PBS, pH 7.4 / 0.1% BSA / 0.02% NaN3 | 2.8 |
M-270 Streptavidin | 1 | 10 (6-7x108 beads/ml) | PBS, pH 7.4, / 0.09% NaN3 | 2.8 |
MyOne Streptavidin C1 | 1 | 10 (7-12x109 beads/ml) | PBS, pH 7.4 / 0.01% Tween®-20 / 0.09% NaN3 | 1.0 |
MyOne Streptavidin T1 | 1 | 10 (7-12 x 109 beads/ml) | PBS, pH 7.4 / 0.1% BSA / 0.02% NaN3 | 1.0 |
The salt concentration and pH (typically 5-9) of the chosen binding/washing buffers can be varied depending
on the type of molecule to be immobilized. Beads with immobilized molecules are stable in common buffers.
DEPC-treatment:
Add DEPC to a final concentration of 0.1% (1ml/L) to Solution A or B. Shake vigorously, incubate for 1 hour at room temperature. Ready to use after autoclaving.
Recipe for PBS buffer pH 7.4:
0.26 g NaH
2PO
4 x H
2O (MW 137.99)
1.44 g Na
2HPO
4 x H
2O (MW 177.99)
8.78 g NaCl (MW 58.5)
Dissolve in 900 ml distilled water, adjust pH if necessary and adjust to 1 liter.
Principle
Add Dynabeads to a sample containing biotinylated molecules. During a short incubation, the biotinylated molecule will bind to the beads. Separate the molecule-bead complex with a magnet. Capture, washing and detection can be optimized for manual or automated use. With indirect capture, the biotinylated molecule is mixed with the sample to capture the molecule-target complex before adding Dynabeads. Indirect target capture can be advantageous when molecule-target kinetics are slow, affinity is weak, molecule concentration is low or molecule-target binding requires optimal molecule orientation and true liquid-phase kinetics.