Correct option is B
Correct Answer: (b)
Explanation: Automated haematology analysers estimate haemoglobin concentration using spectrophotometric principles. Hemoglobin is converted into a stable coloured derivative such as cyanmethemoglobin or sodium lauryl sulfate–hemoglobin. The absorbance of this compound is measured at a specific wavelength and is directly proportional to haemoglobin concentration. Hence, spectrophotometric methods are used.
Information Booster
· Spectrophotometry is based on Beer–Lambert’s law.
· Haemoglobin derivatives absorb light at characteristic wavelengths.
· Cyanmethemoglobin method is a classical reference technique.
· Modern analysers often use SLS–hemoglobin for safer analysis.
· The method is rapid, accurate, and suitable for high-throughput testing.
Additional Knowledge
Sedimentation analysis is used for measurements like erythrocyte sedimentation rate (ESR), not haemoglobin concentration. Mass spectrometry and NMR spectroscopy are advanced analytical techniques used for structural and molecular studies and are not practical for routine clinical blood profiling. Therefore, spectrophotometric estimation remains the standard method for haemoglobin measurement in automated haematology analysers.
