Introduction

Angiotensin-converting enzyme (ACE) is a circulating enzyme that participates in the body's renin-angiotensin system (RAS), which mediates extracellular volume and arterial vasoconstriction. It is secreted by pulmonary and renal endothelial cells and catalyzes the conversion of decapeptide angiotensin I to octapeptide angiotensin II. It plays an important role in blood pressure regulation, and also plays a crucial role in fertilization through its GPIase activity. The enzyme is also able to inactivate bradykinin, a potent vasodilator. It has a molecular weight of 80,073.

This kit was based on sandwich enzyme-linked immune-sorbent assay technology. Anti-ACE polyclonal antibody was pre-coated onto 96-well plates. And the biotin conjugated anti-ACE polyclonal antibody was used as detection antibodies. The standards, test samples and biotin conjugated detection antibody were added to the wells subsequently, and wash with wash buffer. Avidin-Biotin-Peroxidase Complex was added and unbound conjugates were washed away with wash buffer. TMB substrates were used to visualize HRP enzymatic reaction. TMB was catalyzed by HRP to produce a blue color product that changed into yellow after adding acidic stop solution. The density of yellow is proportional to the ACE amount of sample captured in plate. Read the O.D. absorbance at 450nm in a microplate reader, and then the concentration of ACE can be calculated.

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Kit components

1. One 96-well plate pre-coated with anti-human ACE antibody 

2. Lyophilized human ACE standards: 2 tubes (50 ng / tube)                     

3. Sample / Standard diluent buffer: 30 ml

4. Biotin conjugated anti-human ACE antibody (Concentrated): 130 μl. Dilution: 1:100

5. Antibody diluent buffer: 12 ml

6. Avidin-Biotin-Peroxidase Complex (ABC) (Concentrated): 130 μl. Dilution: 1:100

7. ABC diluent buffer: 12 ml

8. TMB substrate: 10 ml

9. Stop solution: 10 ml

10. Wash buffer(25X): 30 ml

Note: Reconstitute standards and test samples with Kit Component 3.

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