The principle commonly used to measure the concentration of a particular analyte in the chemical examination of urine is: Group of answer choices Digital imaging Flow cytometry Reflectance photometry Auto particle recognition
Answer
Principle Used in Measuring Urine Analyte Concentration
In the chemical examination of urine, accurate measurement of specific analyte concentrations—such as glucose, proteins, ketones, bilirubin, and others—is crucial for diagnostic purposes. This process requires a reliable analytical method that can detect subtle colorimetric or chemical changes.
🧪 Most Commonly Used Principle
Among the listed options:
- Digital Imaging – used in advanced diagnostics, not typically standard for chemical urine testing.
- Flow Cytometry – excellent for cellular analysis, but not used for chemical urine analysis.
- Auto Particle Recognition – helpful in urine sediment analysis, not in chemical tests.
- Reflectance Photometry – correct and widely used for detecting color intensity changes on reagent pads of urine test strips.
This principle is extensively used in automated urine analyzers to quantify analytes by measuring the intensity of reflected light from reagent test strips.
🔬 How Reflectance Photometry Works
Reflectance photometry involves shining a light on the colored pad of a urine test strip after it reacts with the urine sample. The amount of light reflected back is inversely proportional to the analyte concentration. Automated analyzers interpret these reflections into quantitative results.