Calculator
HABA Biotinylation Calculator
HABA (4'-hydroxyazobenzene-2-carboxylic acid) is a dye that can be used for quantitation of biotin in a sample. When bound to avidin, the HABA-avidin complex has an absorbance at 500 nm (Ec = 34,000). Due to its higher affinity for avidin, biotin when introduced to a HABA-avidin solution will displace HABA and the absorption at 500 nm will decrease proportionately. Thus, we can utilize this method to estimate the moles of biotin in solution.
This calculator will use the change in max absorbance at 500 nm to estimate the concentration of biotin in solution with Beer's Law. Then it will return a mole-to-mole ratio of biotin to its linked protein (protein concentration must be known).
However, HABA-avidin based assays suffer from some inaccuracies that can be caused by a variety of factors like steric hindrance. For an alternative, see our product: Readiview Biotin Succinimidyl Ester
This calculator will use the change in max absorbance at 500 nm to estimate the concentration of biotin in solution with Beer's Law. Then it will return a mole-to-mole ratio of biotin to its linked protein (protein concentration must be known).
However, HABA-avidin based assays suffer from some inaccuracies that can be caused by a variety of factors like steric hindrance. For an alternative, see our product: Readiview Biotin Succinimidyl Ester
How to use this tool
| Abbreviation | Stands For |
| H+A | HABA + Avidin solution |
| B | Biotinylated Protein solution |
| H+A+B | HABA + Avidin + Biotinylated Protein solution |
- Choose the format that your absorbance was measured in, either cuvette or microplate.
- Enter the volume of H+A.
- Enter the volume of B added to H+A (previous step). If no B was added to solution H+A, leave this field blank or enter "0".
- Enter the Abs 500 of H+A.
- Enter the Abs 500 of H+A+B.
- Enter the molecular weight and concentration of the protein that is labeled with biotin. Example:
Protein MW BSA 66430 IgG 150000 - Enter the dilution factor if your sample was diluted prior to measurement of absorbance.
Data Entry
| Format | |
| Path Length (cm) | |
| Volume H+A (uL) | |
| Volume B (uL) | |
| Absorbance H+A | |
| Absorbance H+A+B | |
| Molecular Weight of Protein | |
| Concentration of Protein Sample (mg / ml) | |
| Dilution Factor | |
Feedback
Have a question or a feature request about this tool? Feel free to reach out to us and let us know! We're always looking for ways to improve!References
This online tool may be cited as follows
MLA | "Quest Calculate™ HABA Biotinylation Calculator." AAT Bioquest, Inc., 26 Apr. 2025, https://www.aatbio.com/tools/haba-biotin-streptavidin-avidin-labeling-calculator. | |
APA | AAT Bioquest, Inc. (2025, April 26). Quest Calculate™ HABA Biotinylation Calculator. AAT Bioquest. https://www.aatbio.com/tools/haba-biotin-streptavidin-avidin-labeling-calculator. | |
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