LimsPulse
Dosage-form testing

Dissolution Test Apparatus

Measures how fast and how completely the drug is released from a tablet or capsule into a liquid medium held at body temperature. A key quality and release test for oral solid dosage forms.

  • Pharmaceutical
  • Generic drug development
  • Nutraceuticals and dietary supplements
  • Veterinary medicines
  • Contract research and testing labs
Photo of a Dissolution Test Apparatus
Photo: Gpkp, CC BY-SA 4.0 (cropped), via Wikimedia Commons
Follow your site SOP
This is a typical operating sequence for learning. Your instrument model and approved SOP take precedence.
STAGE 1

Before you start

  1. 1Check the instrument is within its calibration and PVT due date and has no 'out of order' label.
  2. 2Check the bath water level and cleanliness; top up with purified water if needed.
  3. 3Confirm the method: apparatus, medium, volume, speed, time points, sampling volume and filter.
  4. 4Inspect paddles or baskets for damage, coating chips, bent shafts or deformed mesh.
  5. 5Check that the vessels are clean, unscratched and seated correctly in the centring rings.
  • Do not use a damaged paddle, bent shaft or dented basket; small defects change the flow pattern and the result.
  • Keep the bench free of vibration sources such as shakers, sonicators and centrifuges.
STAGE 2

Medium preparation

  1. 1Prepare the medium exactly as stated, check its pH and record it.
  2. 2Deaerate the medium, for example by warming, filtering under vacuum and stirring under vacuum for a few minutes, or by another validated technique.
  3. 3Measure the volume accurately (by graduated cylinder or by weight) and transfer it gently into each vessel to avoid re-aerating it.
  4. 4Allow the medium to reach 37 ± 0.5 °C and check the temperature in every vessel before adding the units.
  • Do not add medium with a large free fall or vigorous pouring; this puts air back into it.
STAGE 3

Running the test

  1. 1Lower the paddles or baskets to the qualified height and set the rotation speed.
  2. 2For the paddle method, drop one unit into each vessel, timing each drop so all start within the allowed window; for the basket method, load the unit into a dry basket before lowering it.
  3. 3Start the timer and watch the units: note coning, floating, sticking or capsule shells that do not open.
  4. 4At each time point withdraw the sample from the sampling zone within the allowed time tolerance (commonly ±2% of the stated time).
  5. 5Filter immediately through the validated filter, discarding the first few mL as established during method validation.
  6. 6Replace the withdrawn volume with fresh medium if the method requires, or correct the calculation for volume removed.
  • Sample from the same position every time; sampling close to the paddle or wall gives biased results.
  • If a unit sticks to the vessel wall or a capsule floats without a permitted sinker, record it and assess whether the result is valid.
STAGE 4

After the test

  1. 1Analyse the samples promptly or within their demonstrated stability period.
  2. 2Empty and rinse the vessels, paddles and baskets with purified water and dry them.
  3. 3Check the final medium temperature and record it.
  4. 4Complete the instrument usage log and switch off the heater if the bath will not be used again soon.
In LimsPulse · Calibration Management

Keep every Dissolution tester in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.

See how