Resolution(Rs) Calculation by USP Method

1.0 OBJECTIVE

To lay down a procedure for calculating Resolution(Rs) Calculation by USP Method

2.0 SCOPE

This SOP is applicable for calculating Resolution(Rs) Calculation by USP Method in Company Name

3.0 BACKGROUND 

NIL                                       

4.0 RESPONSIBILITY

4.1 All Analytical research personnel shall follow the SOP.      

4.2 Group leader of Analytical  research to ensure the proper and safe disposal of excess samples, expired chemicals, impurities ,reference standard and empty reagent bottles or solvent bottles.          

4.3 Head Analytical research or his designee to ensure overall compliance.

5.0 PROCEDURE

5.1 The separation is a function of the thermodynamics of the system. Substances are separated in a chromatographic column when their rate of migration differs, due to their different distribution between the stationary and mobile phases. 

5.2 The Selectivity Factor, a, and Resolution Factor, Rs, measure the extent of separation between two adjacent peaks.  The Selectivity Factor accounts only for the ratio of the Retention Factors, k', of the two peaks (k'₂/k'₁), whereas the Resolution Factor, Rs, accounts for the difference between the retention times of the two peaks relative to their width.

5.3 The resolution is a measure  of how well two peaks are separated. 

5.4 For reliable quantification, well separated peaks are essential for quantification. The resolution is a critical value when working with complex samples such as drug impurities and degradation products, or when the formulation is complex and excipients might interfere with the quantitative measurements.  Therefore, it is an essential part of the system suitability measurement stage before the quantitative work of these type of samples. 

 Calculation of Resolution by USP method

 

tRB= 11.6

tRA= 8.4

WA= 1.2

WB=1.25

        2(11.6-8.4)

Rs =---------------- = 2.6

        (1.2+1.25)

6.0 ANNEXURES 

Nil