PRACTICAL 3: ASSESSMENT OF QUALITY OF TABLETS AND CAPSULE (5)

EXPERIMENT 5 : DOSAGE PERFORMANCE TEST

Objectives

To determine the actual content of Ibuprofen in Ibuprofen tablet.

Apparatus

Weighing balance, weighing boat

Material

Ibuprofen Tablets (Powder form)

Procedure

1)      0.6856g of pre-crushed ibuprofen tablet powder containing 0.5g of ibuprofen was weighed.

2)      The ibuprofen in powder mixture was extracted with 20mL chloroform for 15minutes and was filtered through a filter paper.

3)      The residue was washed with 3 times of 10 ml chloroform.

4)      The combined filtrate was exposed to hot air by using hair dryer to help it evaporate.

5)      The residue was dissolved in 100 ml 96% ethanol previously neutralized to phenolphthalein solution.

6)      The solution was titrated with 0.1M sodium hydroxide to end point with phenolphthalein solution as the indicator.

7)      The content of ibuprofen was calculated.

Discussion

The Ibuprofen tablets should contain 90% ~ 110% of the labelled ibuprofen content in accordance British Pharmacopoeia. According to the result obtained in the experiment, which recorded 115.94% of ibuprofen content, the ibuprofen tablets being tested was considered to have failed the B.P. test for content of active ingredient.

            There was occurrence of error in process of the experiment that might cause an inaccuracy in the result obtained. Firstly, the titration was not repeated to obtain an average value of the endpoint. This could lead to random error, hence, an inaccuracy in the result. Besides, the stopcock of the burette was detached unexpectedly from the burette for a very brief moment, causing a small amount of NaOH to flow rapidly into the conical flask. Meanwhile, the colour of the solution immediately turned pink while the stop cork was reattached to the burette to stop the flow. Therefore, there is no way to determine whether the amount of NaOH used has reached the endpoint accurately or exceeded the actual endpoint.

Conclusion

The percentage of ibuprofen content is 115.94%, which has slightly exceeded the B.P. standard. Therefore, the ibuprofen tablets have failed the B.P test of content.