REPOSITORY
THE NICOLAUS COPERNICUS UNIVERSITY
IN TORUŃ
is an institutional repository of Nicolaus Copernicus University in Toruń. The task of the Repository is to promote scientific achievements and research conducted at NCU and to support teaching.
Recent Submissions
Programy lojalnościowe dla klientów i inwestorów : istota, ewolucja, wyzwania, 178 s.
(Wydawnictwo Adam Marszałek, 2021) Dziawgo, Danuta
Development of a hydrophilic interaction-based procedure for the extraction, separation, and determination of therapeutic oligonucleotides
(Elsevier, 2025-10-19) Vosáhlová, Zuzana; Bocian, Szymon; Studzińska, Sylwia
Background: For analyzing oligonucleotide impurities and metabolites in serum samples, where mass spectrometry detection is essential, hydrophilic interaction liquid chromatography utilizing fully mass spectrometry compatible mobile phases is the best choice. However, reliable analysis must be preceded by a reliable extraction method providing sufficient and repeatable recoveries. Thus, this work aimed to develop a simple and repeatable methodology for extracting and analyzing modified oligonucleotides differing in length (4mer-14mer), both under hydrophilic interaction conditions.
Results: A comprehensive retention study examining the effects of mobile phase composition and temperature on retention and peak shape was conducted for the zwitterionic and amide columns. Based on the results, the amide column was chosen for further study, mainly because the zwitterionic column does not permit elution of longer oligonucleotides (>10mer). In addition, the amide column exhibits greater robustness (minor effects of tested parameters on chromatographic performance), which ensures higher repeatability. The optimization of mass spectrometry parameters was performed to obtain the highest possible sensitivity, which is well well-known issue because of adducts formation. A validated procedure was applied to analyze enriched serum extracts - a newly synthesized amide-based sorbent was used for the dispersive solid-phase extraction. The conditions for adsorption and desorption, which are driven by a weak ion-exchange mechanism and thus by pH change, were optimized to obtain the highest recoveries.
Significance: A fully hydrophilic interaction-based procedure was utilized for the first time f extraction and analysis of a mixture of 5 modified oligonucleotides differing in length from enriched serum. This method proved to be simple, repeatable, and provides recoveries higher than 75% (RSD <5%).
An intercity investment network dataset of China based on the enterprise registration records (2000–2020)
(Nature Research, 2025) Shu, Tianheng; Yang, Shuo; Cheng, Guangyu; Ren, Yitian; Ren, Yitian; Shi, Fangchen; Derudder, Ben; Liao, Xia
Intercity investment activities among enterprises reflect the flow of capital between cities, thereby directly illustrating the economic connections between them. However, there is currently no publicly available dataset that captures this important feature. In this study, we introduce an intercity investment network (IIN) dataset for China, covering the period from 2000 to 2020, based on 17,273,411 large-scale enterprise registration records. The dataset represents 367 cities as nodes, with investment frequency between cities serving as edge weights to construct both directed and undirected networks. It captures the spatiotemporal patterns of China’s IIN, highlighting dynamic changes in economic connectivity over time and space. The dataset aligns closely with urban networks formed by China’s population mobility and the economic gravity model, is consistent with official records and existing research findings, and satisfies the distance decay effect, thus validating its scientific reliability.
This dataset provides unique opportunities for exploring economic interactions and functional organization between cities, and advancing urban network research in China.
Environmental sustainability in polycentric urban regions: an urban resilience perspective
(Routledge, Taylor&Francis Group, 2025) Yang, Yuting; She, Wei; Derudder, Ben
Regional studies research examining the environmental impacts of polycentric urban structures is often called for, but remains scarce. This study uses urban resilience theory to conceptualise, ethodologically specify and empirically assess the effects. We develop an evaluation system to establish a regional environmental sustainability index and apply it to urban regions across China. Gridded population datasets and inter-city co-patent data proxy morphological and functional polycentricity. Results show that morphological polycentricity positively impacts environmental sustainability, while functional polycentricity only positively affects public stewardship in environmental protection. Urban resilience attributes such as diversity and flexibility have uneven explanatory power on these dynamics.
Application of amino acid-based adsorbents for the extraction of antisense oligonucleotides from serum samples
(Elsevier, 2025-10-10) Studzińska, Sylwia; Ostrowska, Karolina; Vosáhlová, Zuzana; Sasim, Kseniya; Bocian, Szymon
Antisense oligonucleotides are synthetic, short, single-stranded nucleic acid analogues used for several years as an active ingredient of drugs for treating genetic diseases. Their effective sample preparation is a topic that still requires in-depth research. Consequently, amino acid-modified silica adsorbents were utilized for the first time in the dispersive solid-phase extraction of antisense oligonucleotides. The impact of the composition of solvents used for adsorption and desorption was tested (pH, salt type, salt concentration, organic solvent type, and content in the solution). Adsorption of oligonucleotides occurred from water or salt solutions with low pH. Increasing the pH cause increase of recovery contrary to increase salt concentration. Moreover addition of methanol or acetonitrile to elution solvent reduce recovery. The developed method is based on weak ion exchange, with pH playing a key role in the extraction procedure. Thus, the adsorption and desorption are driven solely by the change in pH of the ammonium acetate solution. All tested adsorbents allowed for the efficient recovery of oligonucleotides. Nevertheless, adsorbent with bonded methionine showed the highest efficiency. The recovery depended on the structure of the antisense oligonucleotide (the highest for short and modified ones). The recovery also increases with increasing hydrophobicity of the modification. The developed method was successfully applied to oligonucleotide extraction from human serum samples resulting in a recovery of 91±1%. Only a 10 mM ammonium acetate with pH 4 (adsorption) or 11 (desorpion) is used throughout the whole procedure. The developed procedure is simple, efficient, selective, and environmentally friendly.