- In the years 1988 - 1996 with the late Prof. Emanuel Gil-Av, The Weizmann Institute of Science, Rehovot, Israel (modeling of enantiomer separation in gas liquid chromatography).
- From the year 1996 onward, with Institute of Chemistry, Chemical Research Center, Hungarian Academy of Sciences, Budapest, Hungary (modeling of solute retention in gas chromatography and - as a consequence - derivation of thermodynamic data from the gas chromatographic results).
- From the year 1997 onward, with Faculty of Chemistry, Technical University of Rzeszow, Rzeszow, Poland (investigation and modeling of the intermolecular analyte - analyte interactions (i.e. lateral interactions) in planar chromatography and the impact thereof on the quality of separation).
- From the year 2006 onward, with Prof. Irving R. Epstein from Departament of Chemistry, Brandeis University, Waltham, MA, USA (modeling of chiral inversion of the selected profen drugs, amino acids, and hydroxy acids).
- From the year 2006 onward, with Prof. Hubert Paelinck from Research Group for Technology and Quality of Animal Products, Catholic High School Sint-Lieven, Gent, Belgium (chromatographic analysis of meat and its products).
- From the year 2007 onward, with Prof. Monika Waksmundzka-Hajnos from Faculty of Pharmacy, Medical University of Lublin, Lublin, Poland (thin-layer chromatographic analysis in phytochemistry).
- From the year 2007 onward, with Prof. Shela Gorinstein from Department of Medicinal Chemistry and Natural Products, School of Pharmacy, The Hebrew University of Jerusalem - Hadassah Medical School, Jerusalem, Israel (chromatographic analysis in phytochemistry).