Streptavidin Coated Surface is a powerful and universal instrument for binding any biotinylated molecule.
Streptavidin is the most popular and widely available biotin-binding protein for research methods. It is a tetrameric protein (M.W. 60 kDa) with very high affinity for biotin (Ka=10 –15 M). Biotin is a small molecule which can be conjugated to many proteins without losing or altering their activity. Each protein can bind many biotin molecules. The bond is the strongest known non-covalent biological interaction.
The Streptavidin Coating is a surface treatment that allows to bind any biotinylated molecule (Antibodies – Antigens – Proteins – Peptides – Polysaccharides – Oligonucleotides – DNA fragments etc.). It finds a special application for those molecules which do not offer reliable bonding by passive adsorption or adsorb in an unfavorable orientation. For example, Streptavidin Coated Plates are suitable with ELISA assays protocol.
Each subunit of Streptavidin binds one molecule of Biotin giving at Streptavidin Coated Surface a greater assay sensitivity. Streptavidin-Biotin binding main features are specificity, stability, and affinity.
Biomat’s Streptavidin Coated Products
Streptavidin Coated Surfaces main features
Biomat’s Streptavidin Coated plates and tubes have the following characteristics:
- Ready to use.
- Manufactured under ISO:9001 guidelines.
- Post-coated (blocked) for low non specific binding and long-term stability.
- All lots are tested for uniformity and reproducibility.
- Certificate of Quality is released for every lot.
- For Research Use Only.
Also, Streptavidin Coated Products ensures:
Uniformity
The Streptavidin Coated products show a CV% less than 5 using biotin-HRP as detector and TMB as substrate.
Storage and Stability
The Streptavidin coated products, if unopened, are stable at 2-8°C until the expiration date printed on the label. If opened, store in closed pouch with desiccant and use within the expiration date.
Streptavidin Coated Microplates Specifications
Coating
Streptavidin is coated using 200 µl/well.
Streptavidin Coated Plates parameters and functional features
The following parameters were analysed to determine the functional features of the Streptavidin coated plates,
- Binding capacity towards Biotin.
- Specificity towards Biotin.
- Binding capacity towards Biotinylated IgG.
- Stability tests:
-
- Endurance under strong chemical contacts.
- Shelf life at 37°C.
- Temperature stress (transport simulation).
- Long storage.
- Binding capacity towards Biotin.
1. Binding capacity towards Biotin
Streptavidin coated wells (and BSA saturated control wells ) were incubated with a calibrated Biotin solution. Subsequently, aliquots of this solution, concomitantly with Biotin standards, were mixed with biotinylated peroxidase and transferred into new empty Streptavidin coated wells. From the amount of enzyme bound to the solid phase, the Biotin content of the samples was calculated.
This value was compared with the amount of biotin originally added; from the difference (corrected for-non specific binding of biotin to the control wells), the capacity of the wells for biotin was derived.
12 pmol/ well (200 μl volume)
2. Specificity towards biotin
Streptavidin Coated Wells were incubated with solutions of biotinylated peroxidase and non biotinylated peroxidase (blanks) as a catcher in a ELISA format using TMB as substrate.
3. Binding capacity towards biotinylated HIgG
Streptavidin coated wells were incubated with biotinylated HIgG in an ELISA format using HIgG-HRP as a detector and TMB as substrate.
100 ng/ well (100 μl volume)
4. Stability tests
Endurance under strong chemical contacts
Endurance under strong chemical contacts was determined following method 1 (Biotinylated IgG from 500 to 0 ng/ml) where the first washing step was substituted by the following incubations:
| chemical compound | conditions |
|---|---|
| SDS 0.1% 0.6M NaCl | 56°C 2h |
| 30% Formamide in 0.6M NaCl | 37°C 2h |
| 0.1% Tween® 20 in 0.1M PBS | 37°C 2h |
| 0.05M NaOH | RT 20' |
| 0.2M NaOH | RT 20' |
| standard - 0.1% Tween® 20 in 0.1M PBS | 4 x |
| Urea 8M | 60'-30'-15'-5' |
Shelf life at 37°C
Streptavidin coated wells maintained for 15 days at 37°C in comparison with standard stored at 4°C, were analysed with method 1 (biotinylated IgG =100 ng/ml).
Long storage
Streptavidin coated wells were maintained for 30 months in a warehouse without air conditioning (temperature range from 10°C to 40 °C ) in comparison with samples stored at 4°C (standard condition ).
The results show the exceptional stability of the coating.
Temperature stress (transport simulation)
Stability was checked under different temperatures as those which may occur during transport.
| plate n. | conditions | time |
|---|---|---|
| 1 | 4° C | 10 days |
| 2 | 22°-23° C | 10 days |
| 3 | 37° C 22°-23° C - 20° C 37° C 22°-23° C | 3 days 12 hours 10 hours 3 days 3 days |
Streptavidin Coated Microplates Available
Streptavidin Coated PCR 8 Strip Tube and Plates Specifications
Coating
Streptavidin is coated using 100 µl/tube.
Binding capacity towards biotin
Streptavidin coated PCR 8 strips tubes were incubated with biotin solutions containing biotinylated peroxidase for 30’ R.T. After the washing step, the PCR strips tubes were incubated with TMB and blocked with sulphuric acid 1N. The O.D. values were read at 450 nm
~ 5-6 pMol d-biotin/tube
Streptavidin Coated PCR Products Available
Streptavidin Coated 12x75mm Tubes Specifications
Coating
Streptavidin is coated using 500 µl/tube.
Binding capacity towards biotin
Streptavidin coated tubes 12×75 were incubated with biotin solutions (from 0 to 195.2 ng/ml) containing 4 ng/ml of biotinylated peroxidase for 30’ R.T. After the washing step, the streptavidin tubes 12×75 were incubated with TMB and blocked with sulphuric acid 1N. The O.D. values were read at 450 nm.
~ 28 - 30 pMol d-biotin/tube
