PRACTICAL IV : DOSAGE PERFORMANCE TEST

TITLE

Experiment 4: Dosage performance tests

OBJECTIVES

1.      To determine the time needed for tablet dosage form disintegrate in the different disintegration mediums.

2.      To determine the percentage of amount of Ibuprofen tablet dissolute/dissolve in the dissolution medium.

INTRODUCTION 

For a drug to be absorbed from a solid dosage form after oral administration, it must first be in solution, and the first important step toward this condition is usually the break-up of the tablet; a process known as disintegration. The disintegration test is a measure of the time required under a given set of conditions for a group of tablets to disintegrate into particles.

Solid dosage forms may or may not disintegrate when they interact with gastrointestinal fluid following oral administration depending on their design. For disintegrating solid oral dosage forms, disintegration usually plays a vital role in the dissolution process since it determines to a large extent the area of contact between the solid and liquid. However it is well known that considerable dissolution of the drug can take place before complete disintegration of the dosage form, a phenomenon which depends largely on the mechanism of disintegration and certain physicochemical properties of the drug, such as its solubility. This could be important when considering the motility of the drug or dosage form, and the release of the drug at specific sites, in the gastrointestinal tract. Thus, correlations have been established between disintegration times and dissolution rates for various pharmaceutical tablets.

EXPERIMENTAL METHOD

Apparatus: 1L beaker, 3 test tubes, syringe, 50mL volumetric flask, 10mL measuring cylinder.

Materials and chemical: 3 tablets of Uphamol 500mg, 3 tablets Ibuprofen, buffer solution.

PROCEDURES

Disintegration test procedure

1. The disintegration test equipment was set up by following the instructions in the manual of operation.

2. 500 mL of distilled water was added into the beaker and then added to the disintegration machine. Then, the water was left until the temperature of water is about 37°C.

3. The time was set up to 60 minutes. Three Uphamol tablets were added into each tube with another 3 tablet of from another group. Then, the disk was added into each tube before started the operation.

4.     The tablet in each tube was checked whether it is pass the test or not at the end of the operation.

5. The tablets pass the test if all disintegrate within 60 minutes. If there is any tablet that does not disintegrate, the tablets are pressed. When they disintegrate as we pressed, it also means that the tablet comply with the test.

Dissolution test procedure

1. Dissolution vessel was filled with the buffer solution to 900 ml mark. The temperature was settled to 37°C.

2. One Ibuprofen Tablet was placed into each dry basket assembly.

3. The stirring speed was settled to 150 rpm. The basket assembly was lowered into position in the vessel and the operation was stated.

4.    10 ml samples of the dissolution medium was withdrawal using syringes that include with filter to prevent any solid d particle from drug enter the solution from each vessel for analysis and filter the solution using suitable filter. Sampling should be done from a point half-way between the surface of the dissolution medium and the top of the rotating basket, and not less than 10 mm from the wall of the vessel.

5.    A standard solution of ibuprofen was prepared by diluting 10.0 mg of ibuprofen reference standard to 50 ml with dissolution medium.

6.       4.0 ml of sample solution was diluted and 4.0 ml of standard solution was diluted to 25 ml with dissolution medium in separate 25 mL of volumetric flasks.

7.      The absorption of both solutions was measured in a 1 cm cell at a wavelength of 221 nm.

8.   The percentage amount of ibuprofen dissolved was calculated using the following formula:

At/As × W× P × 900 × 25/2 × 100/200

Where

At= absorbance of sample solution

As = absorbance of the standard solution

 W = weight of ibuprofen reference standard used.

P = purity of ibuprofen reference standard.

9. From the results obtained, determine whether the tablets comply with the requirements of the United States Pharmacopoeia. USP limits: Not less than 75% of the stated amount of C13H18O2 dissolved in 30 minutes.

RESULTS AND CALCULATIONS

Disintegration test for sugar-coated tablets

Our group used three tablets of Uphamol 500mg where each was placed in separated test tubes and then inserted into disintegration medium (distilled water at 38 ̊C). The time needed for the tablets to disintegrate completely is 10 minutes 11 seconds. The tablets can be easily disintegrate in the distilled water which mean it does not required to be tested its disintegration in acidic disintegration medium.

Dissolution test for tablets
One tablet of Ibuprofen is inserted into a dry basket assembly and connected to dissolution vessel.  Then, it is lowered into a dissolution medium (distilled water at 39.3 ̊C) and the stirring speed was set for 30minutes. The operation was started.  After 30 minutes, 10mL of the sample (Ibuprofen solution) is taken out using syringe.  From the 10mL sample, only 4mL is taken out and diluted with buffer solution in the 50mL volumetric flask until calibration mark. 4mL of standard Ibuprofen solution is also be diluted with buffer solution in the 50mL volumetric flask until calibration mark.
The percentage amount of Ibuprofen dissolved is calculated using the formula 

% amount Ibuprofen dissolved= Aŧ/Aṣ x W/50 x 2/25 x P x 900 x 25/2 x 100/200

Where      Aŧ       = absorbance of sample Ibuprofen solution

                  Aṣ       = absorbance of standard Ibuprofen solution

                  W       = weight of Ibuprofen reference standard used (10mg)

                  P        = purity of Ibuprofen reference standard

Ibuprofen solution	Absorbance value
Sample	0.409
Standard	3.068

 % amount of Ibuprofen dissolved     = 0.409/3.068 x 10/50 x 2/25 x 0.98 x 900 x 25/2 x 100/200

= 11.76 %

The tablets are not complying with the requirements of United States Pharmacopeia (not less than 75% of Ibuprofen dissolved in 30 minutes).

DISCUSSION

There are some errors during conducting the disintegration test of drug. One of the errors is the temperature used for disintegration medium which is needed to be ± 37 °C. It cannot be too low as the drug will be disintegrated slower.

The used of different tablets give different time requires for the drugs to be disintegrated. The coated tablets will take longer time to disintegrate compared to the uncoated tablets.

The dissolution test measures the amount of time required for certain percentage of the drug substance in a tablet to go into solution under a specified set of conditions. It describes a step towards physiological availability of the drug substance, but it is not designed to measure the safety or efficacy of the tablet being tested. The dissolution medium must be aqueous and the pH of the medium should be controlled.

Figure 1: Schematic diagram of the dissolution process in vivo.

CONCLUSION

The time needed for the three tablets of Uphamol 500mg to disintegrate completely in the disintegration medium (distilled water) at temperature ± 37 °C is 10 minutes 11 seconds.

While % amount of Ibuprofen dissolved is 11.76 %.It does not comply with the requirements of United States Pharmacopeia (not less than 75% of Ibuprofen dissolved in 30 minutes) as the Ibuprofen tablet used has reached it expiry date.

REFERENCES 

http://www.pharmainfo.net/Tablet%20Evaluation%20Tests/Disintegration/disintegration-tests-dosage-forms

http://id.scribd.com/doc/53984023/Disintegration-for-Tablets