ZINC SULFATE MONOHYDRATE METHOD OF ANALYSIS SOP

ZINC SULFATE MONOHYDRATE METHOD OF ANALYSIS SOP

1.0 OBJECTIVE:

To lay down a procedure for the active raw material of the Zinc sulfate monohydrate from the Pharmacopoeial specifications.

2.0 SCOPE:

This SOP shall be applicable in Q.C laboratory.

3.0 RESPONSIBILITY:

3.1 Q.C Analyst.

4.0 ACCOUNTABILITY:

4.1 Q.C Manager.

5.0 PROCEDURE:

5.1 Characters:

5.1.1 Appearance:

5.1.1.1 White or almost white.

5.1.1.2 Crystalline powder.

5.1.1.3 Colourless.

5.1.1.4 Transparent crystals.

5.1.2 Solubility:

5.1.2.1 Material and equipment:

5.1.2.1.1 Glassware (2 test tubes, 1 spatula, 1 pipette).

5.1.2.1.2 Ethanol (96%).

5.1.2.1.3 Purified water.

5.1.2.2 Sample:

5.1.2.2.1 Small quantity.

5.1.2.3 Method:

5.1.2.3.1 Take a test tube and add small quantity of sample for testing solubility according to B.P specifications.

5.1.2.3.2 Add purified water in test tube 1 and observe.

5.1.2.3.3 Add ethanol (96%) in test tube 2 and observe.

5.1.2.4 Observations:

5.1.2.4.1 The sample in test tube 1 containing with purified water is very soluble.

5.1.2.4.2 The sample in test tube 2 containing with ethanol (96%) is practically insoluble.

5.2 Solution S:

5.2.1 Material and equipment:

5.2.1.1 Glassware (1 50.0ml of beaker, 1 spatula, 1 glass rod, 1 pipette).

5.2.1.2 Analytical weighing balance.

5.2.1.3 Magnetic stirrer.

5.2.1.4 Carbon-dioxide free water.

5.2.2 Sample:

5.2.2.1 2.5g.

5.2.3 Preparation of solution S:

5.2.3.1 Take a beaker of 50.0ml and add sample 2.5g in it.

5.2.3.2 Add in it sufficient quantity of carbon-dioxide free water, dissolve by using magnetic stirrer i.e. SOP

5.2.3.3 Dilute it to 25.0ml with the same solvent.

5.3 Identification tests:

5.3.1 Sulfates test:

5.3.1.1 Material and equipment:

5.3.1.1.1 Glassware (test tube, spatula, beaker, glass rod).

5.3.1.1.2 1.0ml of dilute hydrochloric acid.

5.3.1.1.3 1.0ml of barium chloride solution R1.

5.3.1.2 Sample:

5.3.1.2.1 Solution S.

5.3.1.3 Method:

5.3.1.3.1 Take a test tube and add 5.0ml of solution S.

5.3.1.3.2 Add 1.0ml of dilute hydrochloric acid and 1.0ml of barium chloride solution R1.

5.3.1.3.3 Observe the changes.

5.3.1.4 Observations:

5.3.1.4.1 A white ppt is formed.

5.3.2 Sulfates test:

5.3.2.1 Material and equipment:

5.3.2.1.1 Glassware (1 test tube, 1 pipette, 1 spatula).

5.3.2.1.2 Water bath.

5.3.2.1.3 0.1ml of 0.05M iodine.

5.3.2.1.4 Stannous chloride solution R.

5.3.2.2 Sample:

5.3.2.2.1 Suspension obtained in test 5.3.1.

5.3.2.3 Method:

5.3.2.3.1 Take a test tube add in it suspension obtained from the test 5.3.1.

5.3.2.3.2 Add 0.1ml of 0.05M iodine.

5.3.2.3.3 Observe the changes.

5.3.2.3.4 The suspension remains yellow.

5.3.2.3.5 Add dropwise Stannous chloride solution R.

5.3.2.3.6 Observe the changes.

5.3.2.3.7 It decolorized, boil the mixture on water bath.

5.3.2.3.8 Observe the changes.

5.3.2.4 Observations:

5.3.2.4.1 No coloured ppt is formed.

5.3.3 Zinc test:

5.3.3.1 Material and equipment:

5.3.3.1.1 Glassware (test tube, spatula, beaker, glass rod).

5.3.3.1.2 Strong sodium hydroxide solution R.

5.3.3.1.3 10.0ml of ammonium chloride solution R.

5.3.3.1.4 0.1ml of sodium sulfide solution R.

5.3.3.2 Sample:

5.3.3.2.1 Solution S.

5.3.3.3 Method:

5.3.3.3.1 Take a test tube and add 5.0ml of solution S.

5.3.3.3.2 Add 0.2ml of strong sodium hydroxide solution R.

5.3.3.3.3 Observe the changes.

5.3.3.3.4 A white ppt is formed.

5.3.3.3.5 Add a further 2.0ml of strong sodium hydroxide solution R.

5.3.3.3.6 The ppt dissolves.

5.3.3.3.7 Add 10.0ml of ammonium chloride solution R.

5.3.3.3.8 The solution remains clear.

5.3.3.3.9 Add 0.1ml of sodium sulfide solution R.

5.3.3.3.10 Observe the changes.

5.3.3.4 Observations:

5.3.3.4.1 A flocculent white ppt is formed.

5.4 Assay:

5.4.1 Apparatus:

5.4.1.1 Glassware (1 100.0ml of beaker, 1 50.0ml of beaker, 1 spatula, 1 glass rod, 1 pipette).

5.4.1.2 Analytical weighing balance.

5.4.1.3 Water bath.

5.4.1.4 Magnetic stirrer.

5.4.1.5 Titration apparatus.

5.4.2 Material and reagents:

5.4.2.1 5.0ml of dilute acetic acid R.

5.4.2.2 Purified water.

5.4.2.3 50.0mg of xylenol orange triturate R.

5.4.2.4 Hexamethylenetetramine R.

5.4.2.5 2.0g of Hexamethylenetetramine R.

5.4.2.6 0.1M sodium edetate.

5.4.3 Sample:

5.4.3.1 0.160g

5.4.4 Method of analysis:

5.4.4.1 Take a 500.0ml of conical flask and add 0.160g of sample in it.

5.4.4.2 Add 5.0ml of dilute acetic acid R1 in it; dissolve it by using glass rod.

5.4.4.3 Dilute it to 200.0ml of purified water.

5.4.4.4 Add about 50.0mg of xylenol orange triturate R and Hexamethylenetetramine R, until the solution becomes violet-pink.

5.4.4.5 Add 2.0g of Hexamethylenetetramine R in excess. Dissolve it by using magnetic stirrer i.e. SOP.

5.4.4.6 Set titration apparatus.

5.4.4.7 Titrate with 0.1M sodium edetate until the violet-pink colour changes to yellow.

5.4.4.8 The above procedure is for sample titration and similarly performs the blank titration without using sample.

5.4.4.9 Note down the volume used as shown in Annexure-1.

5.4.4.10 And take average.

5.4.4.11 Calculate percentage purity.

5.4.4.12 Calculations:

5.4.4.12.1 After taking average volume of both blank titration and sample titration. Calculate the volume used by the examined substance by using formula:

Volume used by substance = Blank titration - Sample titration.

5.4.4.12.2 For percentage purity use formula:

%age purity = volume used by substance x factor x 100

Weight of sample

5.4.4.12.3 Put values and calculate %age purity.

5.4.5 Factor:

5.4.5.1 1ml of 0.1M sodium edetate is equivalent to 17.95mg of ZnSO₄.H₂O.

5.4.6 Limit:

5.4.6.1 99.0% to 101.0%.

6.0 REVISION LOG:

Revision No.	Effective Date	Reason
00		New SOP

7.0 REFERENCES:

7.1 The British Pharmacopoeia. Vol II., Official Monograph / Zinc sulfate monohydrate: 2015, pp. 1208.

7.2 The British Pharmacopoeia. Vol V., Official Monograph /Qualitative Reactions and Tests: 2015, pp. 266-270.

7.3 The British Pharmacopoeia. Vol V., Official Monograph /Complexometric Titration: 2015, pp. 281-282.

8.0 ANNEXURES:

Annexure 1: Assay observations and calculations (Complexometric titration).

Annexure: 1

Assay observations and calculations (Complexometric titration)

Complexometric titration

Indicator: ___________________

Weight of sample: ____________ Factor: _____________.

Titrant: _____________________

Sample titration

Sr.#	Initial volume (v_i) (ml)	Final volume (v_f) (ml)	v_f-v_i (ml)
1.
2.
3.

Average volume: _________________

Blank titration

Sr.#	Initial volume (v_i) (ml)	Final volume (v_f) (ml)	v_f-v_i (ml)
1.
2.
3.

Average volume: _________________

Calculations:

Volume used by substance = Blank titration - Sample titration.

%age purity = volume used by substance x factor x 100

Weight of sample

RESULT: ____________________________________________________________

9.0 ABBREVIATIONS:

Abbreviation	Expanded Form
SOP	Standard operating procedure
&	And
No.	Number
Ltd.	Limited
QCA	Quality control active ingredient
F	Format
Q.C	Quality control
Vol	Volume
mg	Milligram
ml	Milliliter
ppt	Precipitate
M	Molar
g	Grams
%	Percentage
R	Reagent
BP	British Pharmacopoeia