Reference samples


This photograph shows a set of reference samples, which appear to date from around the turn of the twentieth century. Reference samples used to be a key tool for synthetic chemists, as they provided examples of pure substances from which points of comparison with newly made compounds could be drawn. If a new batch of an expected compound needed to be identified, tested for purity, or have its physical properties examined, it could be tested alongside an appropriate reference sample, whose values could be used as benchmarks. This particular set of samples is divided into two categories: sugar-containing molecules called glycosides, and molecules isolated from natural sources such as plants – some of which are highly toxic.

This set was made by the pharmaceutical company E Merck, based in Darmstadt, Germany. This city is famous for its scientific institutions and endeavours: from housing the European Space Agency’s mission control since 1967, to creating numerous superheavy elements at the GSI Centre for Heavy Ion Research, Darmstadt was given the title of ‘City of Science’ in 1997.

Merck is still at the centre of many medicinal innovations coming out of Darmstadt: founded in 1668 as a small drug store, it evolved into one of the world’s largest pharmaceutical companies, and specialises in the development and manufacture of new medicines and vaccines – as well as reference samples for other pharmacists, chemists, and physicians to use. However, today’s technologies have lessened the need for reference samples, as computer databases now exist which can provide accurate literature values for many molecular properties without the need for additional, time-consuming testing of the sort described above.

Text by: Yuri Filatov


Merck reference sample set