Michal Wozniakiewicz

Dr. Michal Wozniakiewicz

Laboratory for Forensic Chemistry, Department of Analytical Chemistry, Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
orcid

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2015 in Journal of Chromatography A
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Journal Article
Closed access
PNPaweł Mateusz Nowak
Paweł Mateusz Nowak
Michal WozniakiewiczMichal Wozniakiewicz
Michal Wozniakiewicz
PKPaweł Kościelniak
Paweł Kościelniak

1 May 2008 in Journal of Chromatography A
Verified
Journal Article
Closed access
Michal WozniakiewiczMichal Wozniakiewicz
Michal Wozniakiewicz
RWR. Wietecha-Posłuszny
R. Wietecha-Posłuszny
AGA. Garbacik
A. Garbacik
PKP. Kościelniak
P. Kościelniak

13 October 2021 in Journal of Clinical Medicine
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Journal Article
Open access
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OKOlga Kaczmarczyk
Olga Kaczmarczyk
ADAgnieszka Dąbek-Drobny
Agnieszka Dąbek-Drobny
Michal WozniakiewiczMichal Wozniakiewicz
Michal Wozniakiewicz
PPPaweł Paśko
Paweł Paśko
JDJustyna Dobrowolska-Iwanek
Justyna Dobrowolska-Iwanek
Malgorzata Zwolinska-WcisloMalgorzata Zwolinska-Wcislo
Malgorzata Zwolinska-Wcislo
Intestinal dysbiosis plays a crucial role in the development of inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC). The importance of bacterial metabolites, such as short-chain fatty acids (SCFAs), succinic and lactic acids, as well as environmental factors that affect their production in the course of IBD, remains unclear. The aim of this study was to evaluate a profile of organic acids in the stool of CD and UC patients with different disease activity. We assessed a correlation between used medications, patient’s diet, and SCFA levels. A total of 35 adult patients were included in the study. We did not observe significant differences in the levels of organic acids between the CD and UC groups, irrespective of disease activity, and a control group. However, propionic acid levels were higher in IBD patients who received trimebutine vs. those who did not (p = 0.031). Higher isobutyric acid levels were observed in patients treated with biological drugs compared with those without such treatment (p = 0.014). No significant correlations were found between organic acid levels and the frequency of dietary fiber consumption. Our results reveal a new link between medication use and organic acid levels in patients with IBD.

12 February 2016 in Analytical and Bioanalytical Chemistry
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Journal Article
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JNJulia Nowak
Julia Nowak
Michal WozniakiewiczMichal Wozniakiewicz
Michal Wozniakiewicz
PKPiotr Klepacki
Piotr Klepacki
ASAnna Sowa
Anna Sowa
PKPaweł Kościelniak
Paweł Kościelniak
Seeds of plants from Ipomoea genera contain numerous ergot alkaloids, including psychoactive ergine and ergometrine, and are often abused as so-called “legal highs.” In this work, an analytical method for determination of ergine and ergometrine, and identification of other alkaloids was developed, optimized, and validated. Three extraction techniques, ultrasound-assisted extraction in bath, or with sonotrode, and microwave-assisted extraction were evaluated, and it was concluded that ultrasonic bath is the most suitable technique for extraction of ergot alkaloids. The extraction method was later optimized using a Doehlert experimental design with response surface methodology and used together with the optimized LC-Q-TOF-MS method. The analytical procedure was validated in terms of recovery and matrix effect, repeatability, and intermediate precision. Limits of detection and quantification were 1.0 and 3.0 ng mL–1, respectively, and were sufficient for determination of ergot alkaloids in Ipomoea seeds. The analysis revealed that from five kinds of seeds purchased from different vendors, only three contained ergot alkaloids. Concentration of alkaloids and their relative abundance was similar in samples representative for whole seeds packs; however, when single seeds were analyzed, significant discrepancies in ergine and ergometrine concentrations were detected.

1 April 2014 in Journal of Chromatography A
Verified
Journal Article
Closed access
Michal WozniakiewiczMichal Wozniakiewicz
Michal Wozniakiewicz
RWRenata Wietecha-Posluszny
Renata Wietecha-Posluszny
AMAgnieszka Moos
Agnieszka Moos
MWMarcin Wieczorek
Marcin Wieczorek
PKPaweł Łukasz Knihnicki
Paweł Łukasz Knihnicki
PKPaweł Kościelniak
Paweł Kościelniak

1 March 2014 in Science & Justice
Verified
Journal Article
Closed access
AKAgnieszka Kula
Agnieszka Kula
RWRenata Wietecha-Posluszny
Renata Wietecha-Posluszny
KPKatarzyna Pasionek
Katarzyna Pasionek
MKMałgorzata Król
Małgorzata Król
Michal WozniakiewiczMichal Wozniakiewicz
Michal Wozniakiewicz
Paweł KościelniakPaweł Kościelniak
Paweł Kościelniak