So that medicine does not volatilize: New measuring method detects leaking pharmaceutical packages

Today, extensive testing is done by extremely precise weighing machines. These machines are indeed able to detect tiny weight differences, the test, however, takes a long time.

Engineers at Saarland University have now developed a much more simple and cost-efficient measurement technique which uses gas sensors being able to detect small fluid leakages of less than one milligram per day.

The market-ready method can be applied to various containers and will be presented by the company 3S at Saarland research booth at Hannover Fair from April 19th to 23rd (Hall 2, Stand C44).

Starting from a request from a completely different field, namely the automotive industry, the basic method has been developed at Saarland University. “If a fluid-filled tilt sensor, an important component of many car alarm systems, is defectively produced and shows smallest capillary cracks, its content will evaporate over the course of time. This needs to be detected already during production process, before the sensor is integrated in the car” describes Andreas Schütze, professor for measurement technology at Saarland University, the challenges of industry. Therefore, his team has developed a method which uses extremely sensitive gas sensors instantaneously sniffing if only a thousandth gram of the fluid escapes the container. “This measurement technology can be installed at the end of the production chain in many industrial fields, so that the product is tested there before it leaves the factory” says Schütze.

In contrast to other testing methods, the measurement chamber neither needs to generate a vacuum nor to work at higher temperatures. The device under test is placed in the measurement chamber just for a short time. The chamber only needs to be a little larger than the device itself. Then, ambient air is let in to transport possibly leaking vapors to the gas sensors. These sensors detect within seconds, whether a package is leaking or not, thus allowing a separate test of each device. Meanwhile, the patented method has been adapted to the needs of pharmaceutical companies and chemical industry. There, it is used for process development as well as for final testing. “A company asked us to check their fluid-filled medicinal flasks for leaks and now uses our method for integrity testing”, explains Thorsten Conrad, managing partner of 3S, a Saarland University spin-off company commercializing the technique. For him, the method is not only advantageous due to its significantly simplified handling and the hundred percent hit rates of the gas sensors at quality control. “The measurement technology also prevents considerable costs and damage to the company's image resulting from the need for calling back defective products” explains the engineer from Saarbrücken.

Questions will be answered by:

Prof. Dr. Andreas Schütze
Lehrstuhl für Messtechnik der Universität des Saarlandes
Tel. 0681 / 302 4663
E-Mail: schuetze@lmt.uni-saarland.de
3S GmbH – Sensors, Signal processing, Systems
Thorsten Conrad
Tel. 0681 / 91 003 52
Tel. 0511 / 89 497101 (Telefon am Messestand)
E-Mail: Conrad@3S-ing.de