prepASH Customer Review: Senior QC Lab Technician at DSM

Precisa Gravimetrics AG was delighted to catch-up with and interview Senior QC Lab Technician and QC Lab Technician of the Vitamins Division of DSM, based in Sisseln, Switzerland. DSM has been using Precisa’s prepASH since 2017.

Company Introduction

DSM Nutritional Products is the world’s leading supplier of vitamins, carotenoids, omega fatty acids, UV filters and fine chemicals for the feed, food, pharmaceutical and cosmetic industries. The company has a long tradition as a pioneer in the development of new products, new formulations and attractive areas of application for all industrial sectors. DSM customers are global, regional and local feed and premix companies as well as producers in the areas of food, beverages, infant nutrition, nutritional supplements, pharmaceuticals, personal care, flavours and fragrances.

The site at Sisseln produces Vitamin E, vitamin A, astaxanthin, folic acid, vitamin K1, flavourings, formulations for nutritional supplements and pharmaceuticals, formulations for animal nutrition, liquid formulations and active pharmaceutical ingredients.

Sisseln Site in Switzerland

As part of the Nutritional Products business unit, headquartered in Kaiseraugst, the Sisseln site belongs to the Dutch DSM Group. Around 1,000 of DSM’s global 25,000 employees work here.

How long have you been using Precisa’s prepASH?

At the Sisseln site, two prepASH devices are used. The first prepASH is within the Vitamins Division and has been in use since 2017. Last year, the second device was installed within the Pharmaceuticals Division.

At the Sisseln site, what are the prepASH devices used for?

prepASH is used for dry residues, raw ash and sulphated ash determination. Raw materials, reference substances and, of course, the end products are analyzed. We do not use the ashes for further analyses.

How is your prepASH equipped?

Since we determine sulfated ash, the prepASH is connected to a scrubber. We work with both the 29 and the 12 sample plates.

Do you work according to certain standards (which ones?)

We work according to Pharmacopoeia.

Which method do you use?

We work with different methods. Especially for raw materials we also determine the dry masses.

We have optimized the sulphated ash step for the different products in such a way that it is as short as possible but does not lead to overfoaming and the results have a high reproducibility.

We can run most samples in the prepASH standard crucibles (29 samples per run possible), for difficult samples we use the larger crucibles with a maximum of 12 samples per run.

How many samples do you process with prepASH per week/per year?

We often use prepASH about 2 times a week, but sometimes also daily.

What is the biggest benefit of the prepASH?

prepASH simplifies the workflow enormously, and we can also process more samples per day.

Scientist Using prepASH

Before prepASH, we were able to determine a maximum of 20 dry samples or 8 sulfated ashes per day. Today, we can determine up to 29 samples (dry mass and sulfate ash) in one analysis step.

The time for sample sequence input and weighing is vanishingly small compared to the manual method.

with the stopwatch, so that the times could be kept correctly. Of course, weighing and back weighing was also time-consuming. We estimate that the working time is reduced from 20 min to 5 min per sample, i.e. to a quarter. Since the instrument informs us acoustically as soon as the sulfuric acid has been added or the analysis is finished, all the concentration can be used for other work after prepASH has been started.

For the sulfated ash determination, we worked with pre-ashers (3h, maximum 8 samples) and muffle (3h) and desiccator (1h) and this always

The quality of the analyses is also convincing, e.g. we find a high reproducibility. Another important advantage over the manual method is also the protocol with the graphical weight progression. This allows us to show customers and authorities the progress of the analysis at any time.

Why did you choose the prepASH?

In addition to the above-mentioned reasons of work simplification, sample capacity and quality assurance, and the possibility of carrying out the sulfate ash step directly in the instrument, the space saving was also a decisive factor. In our company, space is limited, and several people work in the same room. Since the prepASH is controlled via the built-in terminal, there is no need for an additional PC on site. The prepASH has a built-in balance so that the laboratory analytical balance is not blocked by the weighing-in and back weighing for moisture and ash. The prepASH itself does not have to be positioned under the fume hood, it is sufficient that the exhaust gas hose is led into the fume hood. The possible connection to the LIMS was also discussed but has not yet been implemented. We transfer the data to prepDATA (PC evaluation tool).

Are you satisfied with prepASH?

In summary: a cool device

– Which allows an enormous simplification of the workflow

– Saves time and space

– Provides reproducible, well logged results


Find out more about prepASH’s TGA Thermogravimetric Analyser: Thermogravimetric Analyzer | Readability – 0.0001 g | Capacity Up to 120 g (