NHS生物素试剂可对溶液中的抗体，蛋白质和任何其他含伯胺的大分子进行简单有效的生物素标记。 这三种试剂仅在间隔臂长度上有所不同，为研究人员提供了优化标记和检测实验的可能性，其中生物素结合的空间位阻是重要因素。
Guidelines (Following is our recommended protocol. This protocol only provides a guideline, and should be modified according to your specific needs). Calculations : For best results, use ≥ 12-fold molar excess of biotin for a 10 mg/mL protein solution or ≥ 20-fold molar excess of biotin for a 2 mg/mL protein solution. 1.Calculate millimoles of biotin reagent to add to the reaction for a 20-fold molar excess: mL protein × (mg protein/mL protein) × (mmoL protein/mg protein) × (20 mmoL protein/mmoL protein) = mmoL Biotin. * 20 = Recommended molar fold excess of biotin for 2 mg/ml protein sample 2. Calculate microliters of 10 mM biotin reagent solution (prepared in Step B.3) to add to the reaction: mmoL Biotin × (1000000 μL/L) × (L/ 10 mmoL) =μL Biotin Biotin Labeling Reaction : 1. Dissolve 1-10 mg protein in 0.5-2.0 mL PBS according to the calculation made in Calculations. 2. Before use, prepare a 10 mM solution of the biotin reagent in an organic solvent such as DMSO. 3. Add the appropriate volume (μL) of 10 mM biotin reagent solution to the protein solution. 4. Incubate reaction on ice for two hours or at room temperature for 30 minutes. 5. To tests the labeled protein by ELISA or Western blot.