Tikkanen I, Fyhrquist F, Forslund T
Clin Sci (Lond). 1984 Aug;67(2):237-41. doi: 10.1042/cs0670237.
Based on a specific binding of labelled inhibitor to the enzyme active centre, a new principle of enzyme assay, inhibitor binding assay (IBA), was developed and applied to measurement of rat serum angiotensin converting enzyme (ACE). Serum diluted 1:50 was incubated with 125I-labelled ACE inhibitor, 351A, at pH 7.0, 37 degrees C, for 2 h. Inhibitor bound to ACE was separated with coated charcoal and results were calculated from a standard curve. The advantages offered by the novel inhibitor binding assay include simplicity, specificity, absence of interference by other enzymes or immunological cross-reactions, and great sensitivity enabling measurement of ACE in concentrations less than 0.1 units/ml. This principle of enzyme assay will not only have potential new applications for research involving ACE but may also be extended to other enzymes.
基于标记抑制剂与酶活性中心的特异性结合，开发了一种新的酶测定原理——抑制剂结合测定法（IBA），并将其应用于大鼠血清血管紧张素转换酶（ACE）的测定。将稀释至1:50的血清与125I标记的ACE抑制剂351A在pH 7.0、37℃下孵育2小时。用包被活性炭分离与ACE结合的抑制剂，并根据标准曲线计算结果。新型抑制剂结合测定法的优点包括操作简单、特异性强、不受其他酶干扰或免疫交叉反应影响，以及灵敏度高，能够测定浓度低于0.1单位/毫升的ACE。这种酶测定原理不仅在涉及ACE的研究中有潜在的新应用，还可能扩展到其他酶。
