To lay down a procedure for preparation of volumetric solutions / reagents / mobile phase & standardization of volumetric solution used for chemical analysis
This SOP is applicable to Quality Control Department
Quality Control Chemist.
5.0 GENERAL INSTRUCTIONS
5.1 All chemicals / solvents used for preparation of volumetric solutions and reagents shall be LR Grade / AR Grade / GR Grade.
5.2 All volumetric solutions / reagent shall be prepared in purified water unless otherwise the use of carbon-dioxide-free water is specified.
5.3 Volumetric Solutions :
5.3.1 All volumetric solutions / reagent shall be freshly prepared once in every three months or whenever the solution shows any fungal growth or sedimentation or deviation of the strength [Molarity / Normality] from the desired value by more than ± 10%.
5.3.2 The restandardization date shall be one month for all volumetric solutions
5.3.3 Records will be maintained in the Volumetric Solution Standardization Record.
5.3.4 Standardization shall be determined in duplicate either by manually or potentiometrically (wherever applicable) as per STP. Strength of volumetric solution, shall be within ± 10..0 % of the specified strength.
5.3.5 Store all volumetric solutions / reagents in borosilicate stoppered glass bottle, protected from heat, air & moisture. Wherever specified in STP, volumetric solutions / reagents shall be stored in amber colored stoppered glass bottles.
5.3.6 Label the volumetric solutions with details :
1.Name of the Solution
2.Strength:- Exact molarity or normality (wherever applicable),
4.Date of Preparation,
6.Date of Standardization,
5.3.7 Label the reagents with details
1. Name of the solution
2. Strength:- Molarity / Normality or percentage w/w or w/v (wherever applicable)
3. Prepared by,
4. Date of preparation,
5. Use before,
Record the details for volumetric solutions :-
1. Name of the volumetric solution,
2. Date of preparation,
3. Date of standardization,
4. Weight of primary standard taken or volume of equimolar / equinormal standard solution (wherever applicable ),
5. Volume of titrant consumed,
6. Normality / Molarity (wherever applicable),
7. Average Normality / Molarity (wherever applicable),
8. Signature of Analyst,
5.3.8 Calculate the strength of the volumetric solution using one of the following formula (wherever applicable)
1. Using volumetric solution of known strength.
S2 = V1 x S1
V1 = Volume of the Standard solution in ml.
S1 = Strength of Standard Solution (Normality or Molarity)
V2 = Volume of test solution in ml.
S2 = Strength of test solution (Normality or Molarity)
2. Using primary standard
Normality / Molarity = W _
V x F
W = Weight taken of primary standard (g/mg)
V = Volume of titrant consumed (ml.)
F = Equivalent factor for corresponding solution.
5.3.9 Shelf life of reagents shall be 3 months, the same shall be prepared freshly wherever it is mentioned in the pharmacopoeia / STP
5.3.10 The volumetric solutions / reagents shall be destroyed after expiry and fresh solution shall be prepared. The expiry of Volumetric solutions is mentioned in the STP.
5.3.11 The volumetric solutions / reagents shall never be used if any fungal growth, sedimentation or precipitation is observed.
5.40 Mobile phase :
5.4.1 Mobile phase should be prepared only with 0.45 m membrane filtered water only. Mobile phase should not be stored beyond 24 hours.
5.4.2 Label of mobile phase should consists of the following details :
1. Product / Material for which the mobile phase is being used
2. Prepared by3.Date of preparation.