Performing the Dissolution Test

Verify that the Equipment is Clean

VERIFY

The analyst is responsible for verification of the physical parameters.

Prepare and Measure Dissolution Media

USP PREPARATION METHOD

  • Heat media to 41°C
  • Vacuum filter through 0.45µm filter
  • Continue to pull vacuum for five additional minutes
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MEASURING MEDIA

Care must be taken in measuring the dissolution media to maintain the volumetric accuracy at ±1%. Volumetric accuracy is based on dissolution media measured room temperature. Alternatively, dissolution media may be weighed.

Introduce Dissolution Media to the Vessel

PREPARE

Media addition has to be done carefully and accurately. Have materials ready for the test, including all sampling equipment.

Adjust the Media Temperature in each of the Vessels

TEMPERATURE

Allow media in each vessel to reach 37 °C ± 0.5 °C and use immediately.

Examine the Six Dosage Units

EXAMINATION

Do not use chipped, cracked or capped
tablets.
Always handle dosage units with gloves (not cotton), forceps or tweezers which will not scratch or damage the surface of the dosage unit.

Record the Dosage Unit Weight

THIS IS AN OPTIONAL STEP

Weight is for information and investigation purposes only. Dosage units must be chosen at random and may not be selected or discarded based on weight.

Record the Information Immediately

DOCUMENTATION

An analyst notebook or an official batch record worksheet must be made available to directly record information during the test.

Prepare to Drop the Tablets

PREPARATION

Lower paddles to proper height, or suspend baskets until ready to begin the test. Apparatus 1 baskets should be tested immediately after placing the tablet or capsule inside and clipping to the shaft. Exposure to humidity can alter test results.

CALIBRATED TIMER

Prepare a calibrated timer to record times when tablets are dropped.

Drop the Tablets

APPARATUS 2

For the paddle apparatus, drop the dosage units into non-rotating medium. They must settle to the bottom of the vessel before rotation of the shaft begins.

IMPORTANT

Visually inspect the dosage forms for air bubbles immediately after dropping. Record any unusual observations.

Withdraw the Sample at the Proper Time

SAMPLING ACCURACY

Withdraw sample at the proper time ± 2% (eg a 30 minute sample must be pulled within ± 36 seconds) and filter immediately. Temperature must be taken a second time at least, generally after the last sample is pulled and before the shaft has stopped.

Filtrate to Stop Test

FILTRATION

Filtration stops the dissolution process and defines the end of the first phase of the test which is basically a sample preparation period executed under strictly controlled physical parameters. Once the sample has been filtered the second phase of the testing begins to determine the analytical concentration of the sample.

Determine Concentration

THE ANALYTICAL FINISH

Analytical concentration is generally determined through UV-Vis spectroscopy or HPLC analysis. HPLC is primarily used for drug products containing multiple active components. The responses from the analytical finish will be used to calculate the amount of sample released from the dosage form within the specific time interval.