Showing posts with label Spectrophotometric Method. Show all posts
Showing posts with label Spectrophotometric Method. Show all posts

Friday, May 17, 2013

Assay of Montelukast Sodium (UV-VIS)Spectrophotometric Method


Assay of Montelukast Sodium (UV-VIS)Spectrophotometric Method.

Preparation of standard solution : Take 50mg of Montelukast Sodium in a 100ml volumetric flask, add 50ml of water and sonicate . Add 10ml of 1M Sodium
Hydroxide solution and dilute to 100ml with water. Transfer 1ml of this solution in a 50ml volumetric flask and dilute to 50ml with o.1N NaOH solution.
Preparation of sample solution :  Crush and finely powder 20 tablets. Weigh an amount of tablet powder containing 50mg of Montelukast Sodium in a 100ml volumetric flask, add 50ml of water and sonicate for about 10 minutes. Add 10ml of 1M NaOH soln. and dilute to 100ml with water, filter. Transfer 1ml of this solution in a 50ml volumetric flask and dilute to 50ml with 0.1N NaOH soln.
Measure the absorbance of the resulting solution at he maximum wavelength 345nm, using 0.1N NaOH as blank.
                                            Abs. of sample X Wt. of standard
% 0f Montelukast Sodium=---------------------------------------X potency of Standard
                                             Abs.of Std. X    Wt. of sample

Assay of Atorvastatin (UV-VIS) Spectrophotometric Method


Preparation of Standard Solution :  Take 10mg. of Atorvastatin Calcium Trihydrade in a 100ml volumetric flask, add 50ml of Methanol and sonicate , dilute to volume with the same solvent. Transfer 5ml of this solution in a 50ml Volumetric flask and dilute to volume with methanol.

Preparation of Sample Solution : Crush 20 tablets finely and weigh an amount of powder tablet containing 10mg of Atotvastatin Calcium Trihydrade in a 100ml Volumetric Flask ,add 50ml Methanol and sonicate , dilute to Volume with methanol and filter. Transfer 5ml of the filtrate in a 50ml volumetric flask and make volume with methanol.

Measure the absorbance of the resulting solutionat the maximum wavelength at 247nm,using a methanol as blank.

Calculation :
                        
                                Absorbance of sample x weight of standard
% of Atorvastatin = …………………………………………… X Potency of Standard                   
                                 Absorbance of Std.x Weght of sample x 1.084