LLS presentations at the 21st GCxGC Symposium & 44th ISCC (Riva del Garda)

From 17 to 22 May 2026, the joint conference comprising the 44th International Symposium on Capillary Chromatography (ISCC) and the 21st GC×GC Symposium invited participants to Riva del Garda, Italy, for a scientific exchange. Labor Lommatzsch & Säger contributed three oral lectures to the conference programme and presented current projects in the fields of GC×GC analysis and the differentiation of aromatic mineral oil hydrocarbons (MOAH), as well as the determination of cyclic siloxanes from silicone materials using HPLC-GC-FID.

ISOLATION STRATEGIES FOR TRI-/POLYAROMATIC HYDROCARBONS AND

DETERMINATION VIA GCXGC-MS/FID

Dr. Lommatzsch presented current analytical approaches for the differentiation of MOAH, focusing on the toxicologically relevant group of tri- and polyaromatics. In particular, he compared strategies for pre-separation using liquid-liquid extraction with DMSO (IP 346 method) with the chromatographic solution developed at the LLS involving selective DACC fractionation. It was clearly demonstrated that the chromatographic approach using DACC offers significant advantages over conventional DMSO pre-separation for the characterisation of MOAH in mineral oil products, both in terms of sample preparation and regarding selectivity and sensitivity, and thus represents an improved alternative to the IP 346 method.

TRANSFERABILITY OF MOAH ANALYSIS FROM THERMAL-MODULATED TO

FLOW-MODULATED GCXGC

N. Wolf demonstrated how the conventional differentiation of MOAH based on the number of aromatic rings can be achieved using flow-modulated GCxGC-FID. Compared to the thermally modulated GCxGC typically used, the technical implementation using a flow modulator enables robust routine differentiation of MOAH at significantly lower acquisition and operating costs, as no complex cooling technology is required. Labor Lommatzsch & Säger demonstrated that flow-modulated GCxGC-FID is ideally suited for determining and characterising MOAH, e.g. as contamination in foodstuffs, in accordance with the recently published guidelines of the European Reference Laboratory for Process Contaminants. (EURL-PC, Analysis of MOSH and MOAH in food by GC×GC, 2025).

APPLICATION OF ONLINE COUPLED LC-GC-FID TO DETERMINE SPECIFIC

MIGRATION OF POTENTIALLY HARMFUL CYCLIC SILOXANES FROM FOOD

CONTACT SILICONE ELASTOMERS

Dr. Eckardt presented the method developed and published by the LLS for the specific determination of cyclic siloxanes D4 to D25 in foodstuffs using online coupled HPLC-GC-FID. Following the toxicological re-evaluation of cyclic siloxanes D4 to D13 by the German Federal Institute for Risk Assessment (BfR), which demonstrated that D4 causes damage to human kidney cells, a specific sum migration limit (SML) for siloxanes D4 to D13 will be introduced in future. Using the analytical method presented, compliance with the SML can be routinely verified, for example, as part of the conformity assessment of silicone articles intended to come into contact with food.