|   | 
        PARAMETER | 
        METHOD-A | 
        METHOD-B | 
       
      
        |   | 
          | 
        EPS | 
        HCZ | 
        EPS | 
        HCZ | 
       
      
        | 1 | 
        Working    λ | 
        267.5 nm | 
        271.5 nm | 
        277 nm | 
        271.5 nm | 
       
      
        | 2 | 
        Beer’s    law limit (μg/ml) | 
        15-75 | 
        5-25 | 
        15-75 | 
        5-25 | 
       
      
        | 3 | 
        Correlation Coefficient (r2)* | 
        0.9994 | 
        0.9996 | 
        0.9994 | 
        0.9996 | 
       
      
        | 4 | 
        Slope    (m)* | 
        0.0202 | 
        0.0704 | 
        0.0202 | 
        0.0704 | 
       
      
        | 5 | 
        Intercept    (c)* | 
        0.0424 | 
        -0.0084 | 
        0.0424 | 
        -0.0084 | 
       
     
       
    *Average of five determination |