Paracetamol Raw Material Testing By UV Method specification & analysis prescribes the requirements with UV Spectrophotometer spectrum and Alternate Method of Analysis on HPLC System and Other Testing procedures.
Paracetamol Raw Material Testing By UV and Purpose
This raw material specification & analysis prescribes the requirements for Paracetamol raw material Testing UV and HPLC Method.
Spread about 1.0 of sample on a clean, dry watch glass and observe the appearance, determination it should be white, crystalline powder.
Sparingly soluble in water, freely soluble in alcohol, very slightly soluble in methylene chloride.
Identification Melting point:-
168 °C to 172 °C
Procedure: Paracetamol Raw Material Testing By UV Method, Grind the Paracetamol sample into a fine powder in a mortar and pack the capillary tube with sample by tapping on a hard surface so as to form a tightly packed column of about 2.5mm to 3.5mm in height. Heat the melting point apparatus until the temperature is about 10 0C below the expected melting point and regulate the rate of rising of temperature at the rate of 1± 0.5 0C per minutes. Insert the capillary tube at around 5 0C below the expected melting point in heating vessel. Continue the heating and note down the temperature at which the sample melts between 168°C and 172°C.
Identification (B) BY UV
Paracetamol Raw Material Testing By UV Method Dissolve 0.1 g in methanol R and dilute to 100 ml with the same solvent. To 1.0 ml of the solution add 0.5ml of a 10.3 g/ml solution of hydrochloric acid R and dilute to 100 ml with methanol R. Protect the solution from bright light and immediately measure the absorbance at the absorption maximum at 249 nm. The specific absorbance at the maximum is 860 to 980.
To 0.1 g add 1 ml of hydrochloric acid R, heat to boiling for 3 min, add 1 ml of water R and cool in an ice bath. No precipitate is formed. Add 0.05ml of a 4.9 g/l solution of potassium dichromate R. A violet colour develops which does not change to red.
Loss on drying
Maximum 0.5%, determined on 1 gm by drying in an oven at 100-105 0C
Procedure: Take a clean and dry wide mouth weighing bottle that has been dried at 105± 2 0C in oven for 30 minutes and cool to room temperature in a desiccator then weigh it (W1). Transfer about 1 grams of sample into the weighing bottle. Weigh the bottle and note down the weight (W2). Calculate the net weight of the sample (W2-W1). Gently shake the bottle to distribute the material evenly. Place the weighing bottle in oven. Remove the stopper and keep it by the side of the weighing bottle or petridish. Close the oven, and dry it at 105 0C for 4 hours. Stop drying, and cool to room temperature. Open the chamber and close the weighing bottle promptly with stopper. Weigh the bottle and note down the weight W3.
Calculate the % loss on drying using the formula.
% of Loss on Drying = W2-W3 x 100
Assay (By titrimetry)
Dissolve 0.300g in a mixture of 10 ml of water R and 30 ml of dilute sulphuric acid R. Boil under a reflux condenser for I h, cool and dilute to 100.0 ml with water R. To 20.0 ml of the solution add 40 ml of water R, 40 g of ice, 15 ml of dilute hydrochloric acid R and 0.1 ml of ferroin R. Titrate with 0.1 M cerium sulphate until a greenish-yellow colour is obtained. Carry out a blank titration.
1 ml of 0.1 M cerium sulphate is equivalent to 7.56 mg Paracetamol.
Limits: 99.0%——– 101.0% (on dried basis)
Assay (By UV)
In House Method
Dissolved 150 mg of Paracetamol to 50 ml of 0.1M Sodium hydroxide, dilute with 100 ml of water, shake for 15 minutes and add sufficient water to produce 200 ml. Mix and dilute 10ml of the filtrate to 100 ml with water. Add 10 ml of the resulting solution to 10 ml of 0.1 M sodium hydroxide dilute to 100 ml with water and measure the absorbance of the resulting solution at the maximum at 257nm. Calculate the content of Paracetamol taking 715 as the value of A (1%, 1cm) at the maximum at 257nm.
Absorbance of sample solution = A
%age of Paracetamol = A x 100/0.00075×715 = Y %
Limit: – 99.0—101.0% (on dried basis)