About us

We investigate the elemental composition of samples, including organic and inorganic materials, chemically pure substances, and technical products. Our analyses determine the contents of carbon, hydrogen, nitrogen, sulfur, oxygen, phosphorus and halogens, requiring only small sample amounts (2-10 mg per analysis).

We also provide methods for determining TOC (Total Organic Carbon content) in solid materials, as well as AOX and POX according to DIN 38409-H14. Several ion analysis methods using Capillary Ion Electrophoresis (CIE) are available, and we are able to develop methods for special analytical requirements.

Our services are available to academic institutions, companies, and private individuals.

The laboratory primarily performs C/H/N/S elemental analyses for the University of Vienna’s chemistry and pharmacy departments, as well as by other Austrian academic institutions involved in preparative chemistry. In addition, the laboratory offers the determination of oxygen, phosphorus and halogen content. All services are provided on a chargeable basis. Accounts are handled within the framework of the Austrian University Act’s "Teilrechtsfähigkeit", which means, among other things, that no sales tax is included.

All analytical methods are optimized for sample amounts of 2-10 mg and achieve an uncertainty of approximately 0.3 wt%, as required in the literature for confirming the assumed chemical composition. The analytical range covers concentrations from 100 to 0.1 wt% and can be extended to 0.01 wt% under suitable conditions.

In addition to our routine services, we are engaged in method development.

Over the past years, we have achieved significant improvements in halogen determination. Since 1996, we have been working on the implementation of ion analysis using CIE. Based on this technique, we have improved the speed and performance of halogen and sulfur determination in the concentration range from 1.0 down to 0.01 wt%.

The Laboratory for Microanalytical Services is one of the oldest analytical facilities at the University of Vienna. It was established in the 1930s to make the elemental microanalysis techniques developed by Fritz Pregl (1869–1930) available to the chemistry institutes in Vienna. 

In 1923, Prof. Fritz Pregl was awarded the Nobel Prize in Chemistry for his pioneering work in developing methods for elemental analysis that required only very small amounts of sample material. His laboratory in Graz, Austria, gained an international reputation and became a leading centre for microanalytical chemistry.

Initially, the methods introduced by Pregl were used by synthetic chemists to verify the composition of the compounds they had prepared. Recognizing the growing importance of these techniques, Hermann Mark (1895-1992), Director of the First Chemical Institute of the University of Vienna (1932-1938), allocated laboratory space for the establishment of a central microanalytical facility.

Following the Second World War, Ludwig Ebert (1894-1956), who became head of the institute in 1946, expanded the laboratory. Around 1960, Hans Nowotny (1911-1996) provided additional laboratory space to accommodate its growing activities. After the reorganization of the chemistry institutes at the University of Vienna in 1958, the Microanalytical Laboratory became part of the Institute of Physical Chemistry.

One of the laboratory's earliest directors was Dr. Kurt Horeischy (1913-1945), who headed the "Microchemical Laboratory" from 1941 to 1944. He is remembered not only for his scientific contributions but also for his tragic death during the final days of the Second World War.

After 1945, the laboratory was headed by Fritz Bühler, who emigrated to the United States in 1948. He was succeeded by Wagner, who joined Ciba-Geigy in Basel, Switzerland, in 1951. Wagner was followed by Padowetz, who later also moved to Ciba-Geigy. In 1956, Dr. Josef Zak was appointed head of the Microanalytical Laboratory. Over the following decades, he became synonymous with elemental analysis in Austria and established the laboratory's outstanding reputation.

From 1989 until his retirement in 2022, the laboratory was headed by Johannes Theiner. Under his leadership, its analytical portfolio was significantly expanded through the introduction of instrumental methods for the determination of halogens, sulfur, oxygen, phosphorus, and total organic carbon.

With the implementation of the Universities Act 2002 (UG 2002), a new internal organizational structure was established at the University of Vienna on 1 January 2005. As part of this restructuring, the Laboratory for Microanalytical Services was assigned to the Faculty of Chemistry and established as an independent unit within its internal organizational structure.

Since 2024, the laboratory has been headed by Dr. Mariusz Wolff.

Throughout its history, method development and the continuous improvement of analytical procedures and equipment have been important aspects of the Laboratory for Microanalytical Services. The laboratory’s analysts not only refined established methods but also developed new analytical procedures and contributed to improvements in the apparatus used for elemental microanalysis.

Historical records, based on undated notes by Josef Zak, document a broad range of research activities. Methods for the determination of sulfur and sulfate were investigated by Abrahamczik, Bühler, Padowetz, and Wagner, while halogen determination methods were developed by Abrahamczik and Wagner. Horeischy, Flunt, and Wagner worked on carbon and hydrogen analysis, with Horeischy already exploring possibilities for partial automation. Flunt and Dirscherl contributed to the development of nitrogen determination methods, while Schweigl investigated a colorimetric method for ammonia determination. Wagner and Schweigl also conducted studies on direct oxygen determination.

Other research projects extended the laboratory’s analytical capabilities to additional elements and specialized applications. Dirscherl and Padowetz developed methods for the determination of gold, boron, and platinum. Flunt investigated the preparation of lead dioxide for use in carbon and hydrogen analysis, while Zak developed procedures for preparing active copper for microanalytical applications. Schweigl also studied the uptake of platinum from acidic solutions using ion exchangers.

Over the years, the main methods for carbon, hydrogen, and nitrogen (CHN) analysis became well established, and method development therefore became a smaller part of the laboratory’s activities. Nevertheless, improvements to existing procedures and the introduction of new analytical techniques continued to play an important role.

In 1989-1990, the analytical method for the determination of chloride and bromide was improved through the introduction of potentiometric silver nitrate titration, which replaced the earlier colorimetric Mohr titration. This modification enhanced the accuracy, precision, and objectivity of the measurements while reducing dependence on visual endpoint detection. 

Later, capillary ion electrophoresis (CIE) was introduced as an analytical technique, enabling substantially lower detection limits without increasing the required sample amount. Beyond the determination of chloride and bromide, CIE is also used for the separation and determination of various other ionic species, including inorganic anions and cations, thereby extending the applicability of the method to a broader range of analytical applications. 

The method continues to be improved and validated in accordance with modern quality assurance requirements and analytical method validation standards.

The Laboratory for Microanalytical Services has been the main laboratory for organic elemental microanalysis in Austria for many years. Since the analytical methods and instruments are now well established, there is less research on developing new techniques in this field.

However, elemental analysis remains an important part of synthetic chemistry. It confirms the elemental composition of newly prepared compounds and provides supporting evidence that the sample is sufficiently pure for publication in many scientific journals.

For more than 90 years, the Laboratory for Microanalytical Services has supported chemical research in Austria by providing accurate and reliable analytical services.

Experimental results confirm these theoretical considerations:
Every analytical method used to characterize a substance has both advantages and limitations. 
Therefore, no single method can prove the identity and purity of a compound on its own. A reliable characterization requires the combination of several complementary techniques.

Chemists often rely on nuclear magnetic resonance spectroscopy for structure determination. However, most routine NMR measurements are carried out in solution. Therefore, impurities that are insoluble in the chosen solvent cannot be detected. In addition, small amounts of impurities may not be visible because NMR is less sensitive than some other analytical methods. Some compounds also produce poor or difficult-to-interpret NMR spectra because of low solubility, paramagnetic properties, which can cause large chemical shifts, significant signal broadening, and reduced spectral resolution. Similar limitations apply to other spectroscopic techniques, as each method provides only part of the analytical information.

Mass spectrometry is a powerful method for confirming molecular weight and supporting structure determination. However, only compounds that can be vaporized and ionized are detected. In mixtures, different compounds have different volatilities and ionization efficiencies. As a result, some impurities may give very weak signals or may not be detected at all. Therefore, a mass spectrum alone cannot prove that a sample is pure.

Elemental analysis, in contrast, is a quantitative bulk method. The amount of each measured element is determined from the whole weighed sample and can be compared with the theoretical composition. Modern instruments usually achieve the ±0.3 wt% accuracy required by many scientific journals. Because the entire sample is analyzed, inorganic impurities and compounds containing large amounts of heteroatoms, such as residual dichloromethane, can often be detected. However, complete combustion is not achieved for every type of compound. Some materials, such as highly fluorinated or thermally stable compounds, may not burn completely and can therefore give inaccurate results.

For these reasons, the combination of elemental analysis with spectroscopic methods such as NMR and mass spectrometry provides a more reliable assessment of both the identity and the purity of a compound than any single method alone.