HEAD of laboratory
- Assoc. Professor Maša KNEZ MAREVCI, Ph.D. (https://cris.cobiss.net/ecris/si/sl/researcher/32659)
Team:
- Assist. Professor Petra KOTNIK, Ph.D. (https://cris.cobiss.net/ecris/si/sl/researcher/14368)
- Full Professor Željko KNEZ, Ph.D. (https://cris.cobiss.net/ecris/si/sl/researcher/4576)
- Assist. Vesna POSTRUŽNIK (https://cris.cobiss.net/ecris/si/sl/researcher/52240)
ABOUT US
The Compartment of Chemistry at the Faculty of Medicine, University of Maribor was established on 1st of November 2004 and renamed into the Department of Chemistry in 2007. The head of the Compartment of Chemistry and the Department of Chemistry was full professor Dr. Željko Knez. In 2021, the department was headed by Assoc. Prof. Dr. Maša Knez Marevci. Researchers work within the framework of teaching and research activities, and their research work is linked to the Laboratory for Separation processes and product design at the Faculty of Chemistry and Chemical Technology, University of Maribor, with other laboratories at the Faculty of Medicine, University of Maribor and with the University Clinical Center Maribor.
Courses:
- CHEMISTRY, Uniform Master's Degree Study Program General Medicine (Assoc. Prof. Dr. Maša Knez Marevci),
- CHEMISTRY, Uniform Master's Degree Study Program Dental Medicine (Assoc. Prof. Dr. Maša Knez Marevci),
- MEMBRANE MASS TRANSPORT PHENOMENA, postgraduate study Biomedical Technology (Full Prof. Dr. Željko Knez).
Research:
The main research activities are separation processes, especially the development of new separation or analysis methods and procedures, and studies of the antioxidant and stability of pharmaceutical and natural active ingredients. Research is increasingly focused on metabolomics and proteomics, especially the development of analytical methods using LC-MS/MS and GC-MS for the determination of large and small molecules, such as proteins, peptides, biomarkers and antioxidant compounds from natural and biological materials. We have successfully implemented working techniques such as liquid, gas, thin-layer chromatography, mass spectrometry, dissolution testing of pharmaceutical active ingredients according to USP and EP standard methods, rheology techniques (rotary viscometer) and measurement of total carbon in liquids (TOC).
Cooperation and services:
The department is strongly linked with the laboratories at the Faculty of Chemistry and Chemical Technology, University of Maribor, at the Faculty of Medicine, University of Maribor and with the University Clinical Center Maribor, working together on several projects within the framework of the Public Agency for Scientific Research and Innovation of the Republic of Slovenia and the program group P2-0046. Cooperation with research organizations and industry includes basic and applied research and service activities. We see opportunities for cooperation in the fields of chemistry, biochemistry, pharmacology, toxicology, proteomics, forensics, medical diagnostics, etc.
We offer methods and applications as part of our state-of-the-art research equipment:
- Development of analytical methods LC-MSMS, GC-MS, HPTLC with development validation.
- Analysis of natural materials, extracts and pharmaceutical substances by LC-MSMS, GC-MS and HPTLC.
- Testing of drug delivery with improved therapeutic efficacy.
- Analysis of rheological properties of highly viscous samples.
- Preparation and analysis of biological samples for the content of biomarkers in medicine.
- Quantification of drugs and their half-products, metabolites in biological and non-biological media.
Ongoing programmes and projects:
- P2-0046: Separation processes and product design (head: Prof. dr. Željko Knez) – program group until 2027. (https://cris.cobiss.net/ecris/si/sl/project/17629)
- J7-50129: Oxidative stress and systemic inflammatory response after cardiac surgery: minimally invasive extracorporeal circulation vs. conventional extracorporeal circulation (head: Assist. Prof. dr. Petra KOTNIK) – period 1.10.2023-30.9.2026. (https://cris.cobiss.net/ecris/si/sl/project/20887)
Equipment: Contact: Assist. Professor Petra KOTNIK, Ph.D.
Liquid chromatography - mass spectrometry (LC-MS/MS) - Agilent 1200 HPLC + Agilent 6460 MSD
Liquid chromatography - mass spectrometry enables qualitative and quantitative analysis of analytes and their metabolites by detecting molar weight of ions and their fragments. LC-MS/MS triple quadrupole (QQQ) with JetStream ionisation offers highly sensitive detection in molecule range between 15 – 3000 Da. The main application of LC-MS/MS is quantification of active compounds and their metabolites from “in vitro” and “in vivo” samples.
Applications:
- Clinical and preclinical studies.
- Therapeutic monitoring of drugs.
- Identification of metabolites, impurities…
- Detection of pesticides in water, food products…
- Detection of macromolecules in medicine and pharmacy – proteins, amino acids, biomarkers, monoclonal antibodies (known compounds).
- Detection of mononucleotides, vitamins, mycotoxins, metabolites, fatty acids, sterols, etc. in biological matrices.
- Forensic applications – the presence of prohibited substances in biological matrices.
- Toxicology – quantification of drugs and their half-products, metabolites in biological and non-biological media.
Headspace - gas chromatography with mass spectrometry (HS-GC-MS) – Shimadzu GCMS – QP2010 Ultra
GC-MS is used in forensics, analyses of pesticides and food safety, pharmacy and clinical toxicology, medicine and in analyses of food and fragrances. The method provides rapid qualitative and quantitative analysis of volatile and less volatile organic compounds from complex samples, determination of molecular weight and composition of unknown organic compounds from complex biological and non-biological samples. Identification of sample components is enabled using mass spectra database (spectrum library).
High performance thin layer chromatography (HPTLC) - Camag
High performance thin layer chromatography (HPTLC) is an analytical method where separation of components is performed on a chromatographic plate. The separation is enabled due to differences in distribution coefficients of the analyte. HPTLC method is used for determination of purity and identification of compounds, for verification of the performance after isolation and purification of compounds and for separation of mixtures which cannot be separated using other methods such as crystallization, distillation, sublimation and others.
Dissolution test after USP in EP standardization methods - Agilent 708-DS
The apparatus is designed for the release of pharmaceutical substances (in different pharmaceutical forms) in different media under USP and EP standard methods. It allows carrying out eight experiments simultaneously with manual sampling. Using this apparatus, the dissolution rate of the substance and change of enthalpy at dissolution can be determined.
Rotational viscometer - Anton Paar Rheolab QC
Rotational viscometer Rheolab QC is an apparatus for measuring shear stress, shear rate, speed, viscosity at different temperatures, and for observing physical changes of materials, such as softening, melting, solidification, crystallization, and elasticity. The apparatus is useful for determination of rheological properties of highly viscous samples (oils, polymers, …).
Total Organic Carbon analyser - TOC Shimadzu
TOC – »Total Organic Carbon« analyser allows indirect measurement of total carbon from organic molecules dissolved in liquids. Sensitivity is determined by detecting carbon after catalytic oxidation. For determination of total carbon (TC), inorganic carbon (IC), total organic carbon (TOC) and non-purgeable organic carbon (NPOC), different measuring methods can be used depending on the sample. TOC is used for determination of organic molecules in drinking water, waste and industrial waters, pharmaceutical waters, in water reaction media, etc.