Leak test with methylene blue


Leaky pharmaceutical packaging can endanger the shelf life and efficacy of packaged medicines. Leak test is therefore a must. This can be done particularly easily and reliably by means of a methylene blue test with the LEAK-MASTER® EASY from Witt.

As particularly sensitive products, medicines require high quality packaging. Even the smallest leaks, which are invisible to the naked eye, render the protective barrier of blister packs, for example, ineffective. Oxygen, moisture and microorganisms can penetrate and can render the medicines unusable.

To test the integrity and tightness of blister packs in particular, the packs are placed in a container with an ethanol-based test liquid containing methylene blue as a dye. The blue dye "creeps" into leaking packages and colours the contents a striking blue. Defective seals or blister cavities can thus be clearly identified. The method is suitable for detecting leaks with a size of at least approx. 10 - 20 µm.

The LEAK-MASTER® EASY from WITT makes the proven methylene blue test particularly fast, reliable and user-friendly: A vacuum is pulled above the water in the test chamber. The negative pressure first extracts the existing gas volume from leaking blisters. As soon as the negative pressure in the test chamber is equalized again, a negative pressure prevails in the leaking blister through which methylene blue liquid is drawn in. The leakage thus becomes quickly visible.

The EASY is low-maintenance, the operating costs are low. Depending on the version, the vacuum can be generated by compressed air or by an electric vacuum pump. Due to the intuitive operation, no specially trained personnel are required. The robust acrylic housing is hygienic and easy to clean. Practical: The test liquid can be easily drained through a valve at the base.

With the optionally available PLUS control unit, testing is even easier and more standardised. The tester simply places the product in the chamber and starts a stored test programme. The required vacuum is pulled automatically and maintained for the desired test duration. All tests are digitally documented and the results can be exported.

The LEAK-MASTER® EASY is available in seven different chamber sizes.

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