ASSESSMENT OF QUALITY OF TABLETS AND CAPSULES

Date of experiment : 23^rd November 2015

Introduction

Like all other dosage forms,tablets and capsules are subjected to those pharmacopoeial standards which deal with ‘‘added substances’’ with respect to their toxicity , interference with analytical methods, etc . However , there are number of procedures which apply specifically to tablets and capsules, and which are designed, not only to ensure that tablets or a capsuled exerts its full pharmacological actions, but also to determine the uniformity of the physical properties of the official tablet/capsule,irrespective of the manufacturer.

Such standard are found in British Pharmacopoeia and United Pharmacopoeia and include , uniformity of diameter , uniformity of weight(mass), content of active ingredients, uniformity of content, disintegration and dissolution. In addition there are a number of quality control procedures, which, though widely applied , are not defined by the pharmacopoeias (non-pharmacopoeial standards) such as thickness, hardness and friability .

The following experiments demonstrate the application of a number of selected physical and dosage performance tests on samples of commercially available tablets and capsules.Students are required to refer to official pharmacopoeias for detailed description of other tests not carried out in this practical session.

There are 5 experiment  test involved with different objective each (follow the link below)

EXPERIMENT 1 : UNIFORMITY OF DIAMETER , THICKNESS AND HARDNESS

EXPERIMENT 2 : TABLET FRIABILITY

EXPERIMENT 3 : UNIFORMITY OF WEIGHT OF TABLETS AND CAPSULES

EXPERIMENT 4 : DOSAGE PERFORMANCE TESTS

EXPERIMENT 5 : CONTENT OF IBUPROFEN (assay)


Questions

1. What are the objectives of the tests for uniformity of diameter and uniformity of content ?

          Content uniformity test is used to ensure that every tablet contains the amount of drug substance intended with little variation among tablets within a batch and to determine whether the individual contents are within limits set with reference to the average content of the sample.  Tablet diameter is an important quality control test for tablet packaging which affects packaging either in blister or plastic container .Tablet thickness is determine by the diameter of the tablet. Without proper normalisation of tablet hardness and compression force data, misleading conclusions may be drawn on formulation behaviour particularly when using different equipment for tableting. We have shown how important the tablet thickness and punch diameter is to normalise the tablet hardness and compression force data to give meaningful comparative data.

     2.  State the types of tablets and capsules that must be tested for uniformity of diameter and uniformity of content?

 For uniformity of diameter, all coated and uncoated tablets and all capsules intended for oral administration are applicable such as coated tablet, effervescence tablet and modified release tablet except enteric tablet, film-coated tablet and sugar-coated tablet. For the capsules, mostly capsules are applicable such as hard capsules, soft capsules, gastro-resistant capsules, modified-release capsules and cachets.

For uniformity of content, it was required for coated tablets, other than film-coated tablets containing 50 mg or more of an active ingredient that comprises 50% or more (by weight) of one tablet, , suspensions in single-unit containers or in soft capsules.

3. Give reasons for the non-compliance to test for uniformity of weight.

The reasons for the non-compliance to test for the uniformity of weight are because of the different amount of granules that put into the die maybe due to the uneven size of granules. Other than that, irregular movement of lower punch will cause variety in the capacity of die space. Next, this problem also can cause by the wrong measurement during weighing. Last but not least, the unwell mixed of the ingredients in blending stage can also cause the non-compliance.

4. Why is dissolution test suitable to be used for batch to batch quality control?

Because the function of the dissolution test is to provide information of the bioavailability of active ingredient and the time release profile of drug into the body can be predicted. It is used for batch to batch quality control by ensuring the consistency of the scale up batch and production batch. This test also ensures that the dissolution profile is same as the pivotal clinical trial batch.

5. Explain the difference found in the procedure for the dissolution test in United State Pharmacopoeia and the British Pharmacopoeia.

There are some differences between the USP and the British Pharmacopoeia. During the dissolution testing in that capsule product, especially those in hard capsules, float because of their fill density is less than 1g mL^-1 is preferably to used Apparatus 1 as stated in the USP while the Apparatus 2 is preferably used for tablets. As for the British Pharmacopoeia, it authorize that the use of any product that floats and it has the most precise specification for one, which it is constructed from an acid-resistant metal wire 1mm in diameter and is described as being a metal cage, which the body are held together by double wires in the shape of a cross. It is constructed such that one of the end scan be opened to place the capsule inside and is closed with clasp. The British Pharmacopoeia simply states that for product that floats when using the Apparatus 2, a glass or metal helix should be used to keep the dosage horizontal at the bottom of the vessel.

In United States Pharmacopoeia, typical acceptance criteria for the amount of active ingredient dissolved, expressed as a percentage of the labelled content (Q), are in the range of 75% to 80% dissolved. In British Pharmacopoeia, the amount of active ingredient dissolves must not less than 70%. In US Pharmacopoeia, if the test failed, a retest may be carried out in three stages with different amount of tablets. In British Pharmacopoeia, if the test failed, a retest may be carried out using the same number of units of tablets 

Conclusion

The tablets and capsules are subjected to different type of tests in order to make sure they have the desired physical strength to overcome the mechanical shock during handling and packaging.The capsules or tablets produced must also give the best therapeutic effect and least side effect when administered into the body . The test must be done before it can be marketed and must follow the standard from Britsh Pharmacopoiea or Unites States Pharmacopoiea .

References

1.      Aulton, M.E. 2002. Pharmaceutics: The Science of Dosage form Design. Edinburgh Churchill Livingstone.

2.      Martin, A.N. 2006. Physical Pharmacy: Physical Chemistry Principles in Pharmaceutical Sciences. Ed. Ke-5. Philadelphia: Lea & Febiger.

3.      Michael E. Aulton. 2007. 3rd Edition Aulton’s Pharmaceutics : The Design And Manufacture of Medicines. Churchill Livingstone Elsevier.

4.      http://www.sciencedirect.com/science/article/pii/S1319016411000028