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MANUAL OF MICROBIOLOGICAL METHODS 



protein). Table 18 gives the factors necessary for calculation. For 

 clarity, a sample calculation is given below. 



Table 18. Protein Estimation by U.V. Absorption 



* For 0.5-cm cells, multiply values in last column by 2. 



Example. 0.2 ml of a protein solution (after protamine sulfate treatment) and 

 2.8 ml of distilled water are pipetted into a cuvette with a 1-cm light path. The 

 reference cuvette contains distilled water. 



Readings obtained : 



280 m/x 

 260 m/x 

 280 



260 



ratio = 



O.D. = 0.273 

 O.D. = 0.248 

 0.273 



0.248 



1.10 



In the first column find 1.10. 



From the third column, find the factor 0.87. 



