Percentage Drug Content

Determination of Percentage Drug Content

Aim: To calculate percentage drug content for given sample of drug (marketed preparation).

Reference: https://papcsg.blogspot.com/2018/12/determination-of-percentage-drug.html

Theory:

Different concentration of a standard Drug solution, when analysed in U V spectrometer at a wave length as given in reference book, drug solution provide a Absorption peak.  

Different peaks help to create a Standard Calibration Curve, this is helpful in determining Percentage Drug Content.

Calibration Curve find as: y = mx + c.

Where, 

y =  absorption peak, x = concentration, m = slope and c = intercept point.  

on putting of value of y, x can easily be determined.

Requirement:

Chemical: Marketed Formulation and Solvent

Equipment: U V Spectrometer and Weighing Machine

Apparatus: Beaker, Volumetric flask and Pipette.

Procedure:

* Preparation of Test Solution:

1. Weigh out 100 mg of powder drug (marketed preparation, may contain excipients) dissolve in 25 ml of solvent (as referred).

Make sure to dissolve it completely.

2. Take 1 ml solution from above preparation and dilute in up to 10 ml of solvent (as referred).

* Determination of Absorbance:

3. Set up the apparatus to wavelength (standard) and set to auto zero.

4. Take sample in to cu bate and start analysis. 

5. If, value is greater than 1, than further dilute from step 2 solution. And repeat the procedure.

Calculation:

Lable Claim for preparation = y mg

Total Weight of preparation = x mg,

x mg preparation contain drug = y mg

1 mg contain = (y/x)

so, 100 mg contain = (y/x) * 100 = A mg (Labeled Drug)

Absorption of test solution = y' 

Calibration Curve,

                       y = mx + c

             ⇒      y' = mx + c (calculate x)

Test Sample Contain drug = ( x . Dilution Factor ) / 1000 = B mg (Test Drug)

[Dilution factor = 25.10.p (p = if again dilution required)]

[1/1000 = Convert µg to mg]

% Drug Content = (Test Drug B/ Labeled Drug A) * 100 = C %

Result:

Percentage drug content was calculated it was found as  C %.

List of Experiments 

Source:

→Jain A. 'Pharmaceutical Instrumental Analysis'. Nirali Prakashan. Pune. Third Edition. 2017.

→Chatwal G. R. Ahmed S. K. 'Instrumental Chemical Analysis'. Himalaya Publication PVT LTD. Mumbai. Edition 2008.