Dosage-form testing
Franz Diffusion Cell (Vertical Diffusion Cell)
A two-chamber glass cell used to measure how fast drug is released from creams, gels and ointments, or permeates through skin. Drug passes through a membrane into a stirred receptor medium that is sampled over time.
- Pharmaceutical (topicals and transdermals)
- Cosmetics
- Research and academia
Follow your site SOP
This is a typical operating sequence for learning. Your instrument model and approved SOP take precedence.
STAGE 1
Setup
- 1Check cells are clean and their receptor volumes and orifice diameters are recorded.
- 2Degas the receptor medium and fill each receptor chamber, tilting to remove bubbles.
- 3Mount the pre-soaked membrane and clamp the donor chamber in place.
- 4Allow the cells to equilibrate to temperature with stirring.
- Check under each membrane for bubbles; tilt the cell to remove them before dosing.
STAGE 2
Dosing and sampling
- 1Apply the stated amount of product evenly over the membrane and start timing.
- 2At each time point withdraw the stated volume from the sampling arm.
- 3Immediately replace with the same volume of fresh, warmed medium.
- 4Run the stated number of cells (commonly six) for each product.
- Keep sampling times exact and stagger cells so each is sampled on time.
STAGE 3
After the test
- 1Analyse samples with a validated method (usually HPLC).
- 2Dismantle and clean cells; discard membranes.
- 3Calculate cumulative release correcting for amounts removed at earlier samples.
In LimsPulse · Calibration Management
Keep every Franz cell in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.