Please find below the reason " Why should a good laboratory go for Nephelometer?"

1. What is Turbidimetry?

TURBIDIMETRY is the measurement of the decrease in the intensity of light as it passes through a solution of particles.  Turbidimetry is measured using instruments such as photometers or calorimeters.

Turbidimetry is the technology used to protein assays such as Apolipoproteins, Lp(a), CRP, RF, ASO, C3, C4, Immunoglobulins etc...


2. What is Nephelometry?

NEPHELOMETRY is defined as the detection of light energy scattered towards a detector that is not in the direct path of the transmitted light.  Common nephelometers measure scattered light at right angles to the incident light, but some have detectors placed at angles of 60-70.  This enables to take advantage of the increased forward scatter intensity caused by light scattering from large particles.  The amount of light scattered is propotional to the concentration of antigen or Antibody in the solution.


Nephelometry and turbidimetry are the most widely used methods for the estimation of proteins because of their speed and ease of use.


3.  COMPARISON of Nephelometry, Turbidimetry and RID:
 
Nephelometry methods are more sensitive than turbidimetric methods, with a detection limit of approx. 10ug/mL whereas the detection limit of Turbidimetry methods are 20 to 30 ug/mL.  

RID can detect a minimum of 10-20 ug/mL but they have a higher run to run coefficient of variation (CV) of 5 to 15% compared to nephelometry with less than 5% CV.

Nephelometry and Turbidimetry methods are fast as compared to RID (24-48 hrs).

Nephelometry shows a slightly better detection limit as compared to  turbidimetry in case of lipeamic samples and also in case of purer media such as CSF.

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