Extreme challenges to the purity and cleanliness of a laboratory for ultra-trace analytics

(Copyright: Montanuniversität Leoben)

Mass spectrometry with an inductively coupled plasma (ICP-MS: inductively coupled plasma mass spectrometry) is now so sensitive that ultra-trace levels below 1 ppt (parts per trillion; parts per billion; ng/kg or pg/g) can be achieved. However, to fully exploit the detection capabilities of this method, the analytical laboratory must be appropriately designed, because a single particle from the ambient air could contaminate the sample to such an extent that the results can no longer be used. An example from the Chair of "General and Analytical Chemistry" (AAC) at the Montan University in Leoben (MUL), Austria, will demonstrate how easily particles can be avoided. (1) MUL stands for circular economy-oriented systems and materials research in the sense of "Circular Engineering" and is known as Austria's "Raw Material University".

After Prof. Prohaska was appointed to the Chair of AAC in Leoben, a comprehensive renovation of the MUL's chemistry building was necessary, including the creation of cleanroom conditions to operate multiple ICP-MS devices. The desired cleanroom conditions were achieved, among other ways, with 8 laminar flow boxes from Spetec GmbH, thereby locally reaching a cleanroom class (ISO 5). The most precise device is a high-resolution ICP-MS with a multi-collector detector array, which can determine the concentration of an element in the ppt range and its isotopic composition with extreme precision. Currently, the AAC chair is analyzing 7000-year-old archaeological artifacts from an excavation of a settlement in Lower Austria (Asparn) by measuring strontium isotopes (87Sr/86Sr) in teeth and bones and comparing them with the environment. Since bone finds indicate violent conflicts, the question arises as to where the intruders came from and which trade relations had already been established at that time. To do this, differences in isotope ratios in tiny samples (smallest drill holes from teeth) must be measured in the ppm range. Every contamination must therefore be avoided so that millennia-old traces are not erased.

The company Spetec GmbH has decades of experience in atomic spectroscopy as well as in the development and application of cleanroom and air purification systems for analytical chemistry, enabling them to quickly and cost-effectively achieve the required purity in laboratories.

(1) https://aach.unileoben.ac.at