Based on the provided information, the procedure described is an enzymatic and colorimetric method used for measuring urea concentration in a specimen.
This specific procedure leverages the action of an enzyme called urease to detect and quantify the amount of urea present.
Understanding the Measurement Procedure
The procedure involves a chemical reaction sequence that ultimately produces a colored substance proportional to the initial amount of urea. Here are the key steps involved:
Step 1: Enzymatic Hydrolysis of Urea
- The core of the procedure begins with the enzyme urease.
- Urease acts specifically on urea, breaking it down through a process called hydrolysis.
- This hydrolysis reaction yields two main products:
- Ammonium ions (NH₄⁺)
- Carbon dioxide (CO₂)
Step 2: Formation of a Colored Complex
- The newly formed ammonium ions are crucial for the next step.
- These ammonium ions react with other chemicals present in the solution, specifically chloride and salicylate.
- This reaction results in the formation of a distinct blue-green complex.
Step 3: Colorimetric Measurement
- The intensity of the blue-green coloration developed in Step 2 is directly proportional to the concentration of urea that was initially present in the specimen.
- To measure this coloration, a technique called colorimetry is used.
- A spectrophotometer is employed to measure the amount of light absorbed by the colored solution at a specific wavelength.
- The measurement is taken at 600 nm.
This measurement at 600 nm allows for the quantification of the blue-green complex, which in turn indicates the original concentration of urea in the sample.
Summary Table of the Procedure Steps
| Step | Action | Key Components Involved | Resulting Product | Purpose |
|---|---|---|---|---|
| 1: Enzymatic Action | Urease hydrolyses urea | Urea, Urease | Ammonium Ions, CO₂ | Breakdown of urea |
| 2: Color Formation | Ammonium ions react with other substances | Ammonium Ions, Chloride, Salicylate | Blue-Green Complex | Creation of a measurable colored signal |
| 3: Measurement | Intensity of blue-green color is measured | Blue-Green Complex | Absorbance reading at 600 nm | Quantification of urea concentration |
This method is widely used in clinical laboratories to determine urea levels in blood or urine, providing valuable information for diagnostic purposes.
