SOP for Suppository Tester: Operation, Maintenance, Calibration

In short: This example SOP describes how a QC analyst sets up, operates, cleans and calibrates a suppository disintegration tester (water bath with a rotating basket assembly). Calibration covers basket rotation, timer and bath temperature, plus a visual check of the sieve (wire mesh). Adapt the make, model, frequency and limits to your own quality system and the current pharmacopoeia.

1. Objective

To describe the procedure for handling, operation, maintenance and calibration of the suppository tester apparatus.

2. Scope

This example SOP applies to a suppository tester (example: ELECTROLAB, model ESDT-3) in the Quality Control department of the manufacturing facility. Replace the make and model with your own equipment and follow the manufacturer’s manual.

3. Responsibility

• Analyst / Section Head (or designee): follow this SOP, record usage and report faults.
• Head of Quality Control (or designee): ensure implementation and calibration schedules are met.
• Quality Assurance: review calibration records and out-of-tolerance events.

4. Procedure

4.1 Preliminary checks and precautions

1. Fill the water bath up to the marked level.
2. Connect the heater lead and external temperature probe to the sockets at the rear of the instrument.
3. Connect the mains cord to a 230 V AC socket with proper earthing. Do not use the instrument without earthing.
4. Never switch the mains on if the tank is empty or below the marked level.
5. Make sure the heater connection is firm and not loose.
6. Do not use excessive force when fitting or removing the basket assembly.
7. Pour water gently so that it does not spill outside the bath.
8. Do not slide the bath on the base plate to move it; slide it along the guide on the base plate of the instrument. Do not lift it vertically.
9. Place the basket stand vertically in the bath, aligning the disc so that the stand fits properly.
10. Do not turn the temperature knob while it is locked; unlock it first. Do not use pointed objects to set parameters.
11. Do not use aggressive material or strong solvents to clean the bath or basket stand.
12. Replace a blown fuse only with one of the correct rating.

4.2 Operation

1. After confirming the set-up is correct, switch on the mains and then the power switch at the rear of the instrument.
2. Switch on the stirrer motor.
3. The display shows the bath temperature.
4. Set the timer steps.
5. Set the required temperature: press and hold the push-button switch, unlock the knob, turn it clockwise or anticlockwise to the required value, then lock the knob.
6. Let the bath reach the set temperature.
7. Press the RESET key on the front panel.
8. Load the suppositories into the basket and lower the basket stand vertically into the bath, with the disc positioned so the stand fits properly.
9. Press the RUN/HALT key to start the test. After each set period the basket assembly rotates by 180°, for up to 6 steps.
10. After the test, record the result in the analytical record and make an entry in the equipment usage logbook.

Test temperature and acceptance time depend on the product specification and the pharmacopoeia you follow (for example Ph. Eur. 2.9.2 or the Indian Pharmacopoeia). Use the figures from the applicable monograph or approved specification.

4.3 Cleaning and maintenance

• After use, switch off, disconnect from the mains and drain and clean the bath and basket stand with water and mild detergent; rinse and dry.
• Check the heater lead, probe and mains cord for damage before use.
• Keep the instrument covered when not in use and arrange preventive maintenance as per the equipment schedule.
• Equipment under repair or overdue for calibration must carry an “Out of service” label and must not be used.

4.4 Calibration

Example in-house criterion: calibration frequency is quarterly. Define the frequency from your own risk assessment and the manufacturer’s recommendation.

Basket rotation. Record the rotation of the basket for each of the six steps at the preset interval. Example acceptance criterion: after each set period the basket assembly rotates 180°.

Timer. Set the timer to 5 minutes, press start and start a calibrated stopwatch at the same moment. Note the stopwatch reading when the alarm sounds. Repeat for 10, 15 and 20 minutes. Compare each reading with the set time using your approved tolerance (example in-house criterion; state it in your calibration data sheet).

Heater / bath temperature.

1. Set the water-bath temperature to 36.5 °C.
2. Set the timer to 60 minutes and start the apparatus with the RUN/HALT key.
3. Record the temperature of the water in the bath, using a calibrated thermometer, at 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 and 60 minutes.

Example in-house criterion: every reading must be within 36 °C to 37 °C.

Sieve (wire mesh) integrity check. Inspect each sieve against a bright light for:

• intact openings,
• cracks or abrasion,
• dents.

Acceptance: no defect visible. If the sieve fails, replace it and record the replacement.

Record all calibration results on the calibration data sheet (Annexure I). Affix a calibration status label showing date performed and due date. If any parameter is out of limit, take the instrument out of use, raise a deviation or incident and assess the impact on tests performed since the last good calibration.

4.5 Records and retention

Record every use in the equipment usage logbook. Calibration records, usage logs and test records are GMP records: keep them at least 1 year after the expiry date of the respective product batch (EU GMP Part I, Chapter 4, section 4.11, or 5 years after QP certification if longer; 21 CFR 211.180(a)), and longer if local law or the marketing authorisation requires.

5. Training

Trainer: Head of Quality Control. Trainees: section heads, analysts and officers who use the instrument.

6. Distribution

Controlled copy 1: Head, Quality Assurance. Controlled copy 2: Head, Quality Control. Master copy: Quality Assurance.

7. Annexure

Annexure I: Calibration test data sheet.

8. Abbreviations

QC: Quality Control. SOP: Standard Operating Procedure. QA: Quality Assurance. QP: Qualified Person.

Frequently asked questions

What is a suppository disintegration test for? It shows whether a suppository or pessary softens, melts or breaks apart within a stated time under controlled temperature conditions, as a quality check on the dosage form.

Why is the bath temperature calibrated? The result depends on the medium being close to body temperature, so the display and the actual temperature must agree within the approved limits.

Can I calibrate the timer with my phone? Use a calibrated stopwatch with a certificate traceable to national standards, not an uncontrolled device.

See also: SOP for operation and calibration of disintegration tester apparatus, SOP for calibration, melting point apparatus operation and calibration.

References

• Equipment manufacturer’s user manual (model-specific).
• European Pharmacopoeia, general chapter 2.9.2, Disintegration of suppositories and pessaries (current edition).
• Indian Pharmacopoeia, general chapter on disintegration test (IPC, ipc.gov.in; current edition).
• EudraLex Volume 4, Part I, Chapter 4: Documentation, section 4.11 (retention).
• US 21 CFR 211.160(b)(4) (calibration of laboratory instruments under a written programme), 211.180(a) (record retention) and 211.68 (automatic, mechanical and electronic equipment).

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