Szabolcs Béni | Semmelweis University (original) (raw)

Papers by Szabolcs Béni

Fitoterapia, 2018

Lichenan from Cetraria islandica (L.) ACH. induces cellular differentiation of human keratinocyte... more Lichenan from Cetraria islandica (L.) ACH. induces cellular differentiation of human keratinocytes. Fitoterapia 129, 226-236.

Fiatal Gyógynövénykutatók Fóruma, 2017

Journal of Chromatography A, 2016

Herein we report on the synthesis, characterization and the novel capillary electrophoretic use o... more Herein we report on the synthesis, characterization and the novel capillary electrophoretic use of octakis-(2,3-di-O-methyl-6-O-carboxymethyl)-␥-cyclodextrin sodium salt (ODMCM). ODMCM is the first single-isomer carboxymethyl-␥-cyclodextrin that is fully methylated on its secondary side and carries ionizable carboxymethyl functions on its primary side. ODMCM was prepared with high isomeric purity through a four-step synthetic procedure. The purity of each intermediate was characterized by appropriate chromatographic methods, while the isomeric purity of the carboxymethylated product was determined by an HPLC method using a CD-Screen-IEC column and by a capillary electrophoretic method using indirect UV detection, as well. The structural identification of the ODMCM was carried out by 1D, 2D NMR spectroscopy and ESI-MS. The acid-base characterization of the chiral selector was carried out by 1 H NMR-pH titration. The chiral separation ability of the synthesized selector was studied by chiral capillary electrophoresis. ODMCM was used as a background electrolyte additive to separate enantiomers of representative pharmacologically significant model molecules such as propranolol, citalopram, ketamine, tapentadol and dapoxetine. The effects of the selector concentration and the pH of the background electrolyte on the enantiorecognition properties were investigated. 1 H NMR spectroscopy was further applied to get deeper insight of the host-guest inclusion complex formation. The pH-dependent enantioselectivity of this new single-isomer chiral selector was demonstrated by chiral capillary electrophoresis and 1 H NMR spectroscopy.

Biomedical Chromatography, 2016

Feverfew (Tanacetum parthenium L., Asteraceae) is a perennial medicinal plant which has been used... more Feverfew (Tanacetum parthenium L., Asteraceae) is a perennial medicinal plant which has been used to alleviate the symptoms of migraine, headache, rheumatoid arthritis and possesses numerous pharmacological activities. An Ultra high performance supercritical fluid chromatographic method (UHPSFC) was developed and validated in accordance with the ICH guideline in order to determine the camphor content of the volatile oil, which was outstandingly accurate, precise, robust and selective. The method was validated for specificity, accuracy (100.2%), repeatability and intermediate precision, linearity (r 2 > 0.999), limit of detection (2.055 µg/ml), limit of quantification (6.228 µg/ml) and robustness. The common range of accuracy and linearity was between 0.125-1.000 mg/ml. Steam distillation was carried out in order to study the essential oil yield of three different Tanacetum parthenium L. samples originated from Hungarian medicinal herb collections. The camphor content of the essential oils from the aerial parts of feverfew samples from different origin was compared. Although the composition of the essential oil is well reported, a validated quantitative UHPSFC method for the determination of the constituents is presented herein for the first time.

Journal of Chromatography A, 2014

In our study, over 20 charged cyclodextrin (CD) derivatives were studied for enantiospecific host... more In our study, over 20 charged cyclodextrin (CD) derivatives were studied for enantiospecific host-guest type interactions in CD-modified capillary electrophoresis. Tadalafil stereoisomers are non-charged; therefore, their electrophoretic separation poses a challenge. Several candidates of both positively and negatively charged hosts were found to be effective for the enantioseparation. Eight out of the beta derivatives and three of alpha derivatives (including sulfated, sulfoalkylated, carboxyalkylated and amino derivatives) resolved all four stereoisomers partially or completely. Cavity size-dependent absolute enantiomer migration order (EMO) reversals were observed in the case of sulfopropyl

ELECTROPHORESIS, 2011

An aqueous capillary electrophoretic method was developed for chiral analysis of the novel anti-d... more An aqueous capillary electrophoretic method was developed for chiral analysis of the novel anti-diabetic drug, sitagliptin. The acid-base profiling of the analyte was carried out using both capillary electrophoresis and nuclear magnetic resonance pH titrations. The apparent complex stability and chiral separation properties were investigated with 30 different cyclodextrins under acidic conditions. The effect of concentration and pH of the BGE, temperature of the capillary, and the type and concentration of the chiral selector on the enantiomer resolution were thoroughly investigated. The effects of dual cyclodextrin systems on separation were also extensively studied. Complete separation of racemic sitagliptin with good resolution (R S 5 2.24) was achieved within a short time (15 min) with optimized parameters (101C, pH 5 4.4, 40 mM phosphate buffer) of a sulfobutylether-b-cyclodextrin (averaged degree of substitution $4) and native b-cyclodextrin dual system. The averaged stoichiometry of the inclusion complex was determined using the Job plot method with both 1 H and 19 F NMR experiments and resulted in a 1:1 complex. The structure of the inclusion complex was elucidated using 2-D ROESY NMR experiments.

Molecular pharmaceutics, 2018

The electrospun nanofiber-based orally dissolving webs are promising candidates for rapid drug re... more The electrospun nanofiber-based orally dissolving webs are promising candidates for rapid drug release, which is due to the high surface area to volume ratio of the fibers and the high amorphization efficacy of the fiber formation process. Although the latter is responsible for the physical and/or chemical instability of these systems. The primary aim of the present study was to elucidate how the addition of polysorbate 80 (PS80) and hydroxypropyl-β-cyclodextrin (HP-β-CD) influenced the electrospinning process, the properties, and the behavior of the obtained nanofibers. In order to reveal any subtle changes attributable to the applied excipients, the prepared samples were subjected to several state of the art imaging and solid state characterization techniques at both macroscopic and microscopic levels. Atomic force microscopy (AFM) revealed the viscoelastic nature of the fibrous samples. At relatively low forces mostly elastic deformation was observed, while at higher loads plasti...

Journal of Chromatography A

International Journal of Molecular Sciences

Mitragynine (MTR), the main indole alkaloid of the well-known plant kratom (Mitragyna speciosa), ... more Mitragynine (MTR), the main indole alkaloid of the well-known plant kratom (Mitragyna speciosa), is one of the most studied natural products nowadays, due to its remarkable biological effects. It is a partial agonist on the opioid receptors, and as such relieves pain without the well-known side-effects of the opioids applied in the clinical practice. MTR and its derivatives therefore became novel candidates for drug development. The poor aqueous solubility and low bioavailability of drugs are often improved by cyclodextrins (CyDs) as excipients through host-guest type complex formation. Among the wide variety of CyDs, sulfobutylether-beta-cyclodextrin (SBEβCyD) is frequently used and official in the European and U.S. Pharmacopoeia. Herein, the host-guest complexation of MTR with βCyD and SBEβCyD was studied using chiroptical and NMR spectroscopy. It was found by NMR measurements that MTR forms a rather weak (logβ11 = 0.8) 1:1 host-guest complex with βCyD, while the co-existence of t...

Phytochemical Analysis, 2020

Introduction: The root of the Ononis species has been used internally and externally in ethnomedi... more Introduction: The root of the Ononis species has been used internally and externally in ethnomedicine for centuries and contains biologically valuable isoflavonoid compounds. Therefore, it is important to obtain quantitative information about the isoflavonoid profile of these plants. Objectives: In this article we aimed to develop an optimised sample preparation protocol alongside a validated method for the quantitative measurement of isoflavones, isoflavanones and pterocarpans in the form of glucosides and aglycones, in order to compare the specialised metabolites of Ononis spinosa L. and O. arvensis L. Material and methods: Quantitative determination was carried out by the means of ultra-performance liquid chromatography coupled with ultraviolet diode-array detection (UPLC-UV-DAD). Results: An optimised sample preparation method was developed to transform malonyl glucosides to their glucosidic forms. Chromatographic methods were created for the baseline separation of isoflavones, isoflavanones and pterocarpans alongside with their glucosides. Altogether 12 compounds were evaluated quantitatively in samples of O. spinosa and O. arvensis. Conclusion: As a result, no characteristic change could be observed between the two species regarding their isoflavonoid pattern.

Quantitative phytochemical characterisation of the chief flavonoid aglycones in the hydrolysed &l... more Quantitative phytochemical characterisation of the chief flavonoid aglycones in the hydrolysed Lysimachia extracts revealed the dominance of kaempferol, quercetin and myricetin in L. vulgaris, L. nummularia, L. punctata, L. christinae, L. ciliata and L. clethroides, respectively. Due to the significant radical scavenging capacity of the samples, the contribution of the individual aglycones to the total antioxidant activity became of interest. Therefore, a HPLC method coupled to pre-column DPPH scavenging assay was developed. Differences in the six Lysimachia species' phenolic composition regarding their participation to the antioxidant activity were revealed. The participation of the three investigated flavonoids to the radical quenching activity was the highest (91.2%) in the L. vul...

ELECTROPHORESIS, 2019

The exhaustive primary-side alkylation of cyclodextrins has never been achieved directly. The und... more The exhaustive primary-side alkylation of cyclodextrins has never been achieved directly. The undesired and simultaneous derivatization of the secondary hydroxyl moieties generates intricate isomeric mixtures that are challenging to purify, analyse and characterize. The aim of this study was to develop a chromatography-free and up-scalable strategy towards the preparation of per-6-O-methylated cyclodextrin and to test the compound as potential chiral selector. The target molecule was prepared according to a five-step synthesis by using methyltriphenylphosphonium bromide as catalyst under heterogeneous conditions. The removal of benzyl moieties, used as temporary secondary-side protecting groups, was attained by applying hydrazine-carbonate in the presence of Pd/C. All the intermediates were obtained in high yields, thoroughly characterized and their purity was assessed by ad-hoc developed HPLC methods. The per-6-O-methylated ␤-cyclodextrin showed promising chiral recognition ability as background electrolyte additive in cyclodextrin-modified capillary electrophoresis using the recreational drug methylene-dioxypyrovalerone as model compound. Additionally, a model for the inclusion geometry between the single isomer host and the selected drug was developed based on the extensive 2D NMR analysis. The versatility of the proposed synthetic strategy opens the way to the industrial production of homogeneously primary-alkylated cyclodextrins and to their wide application in chiral separation of various drugs.

Journal of chromatography. A, Jan 9, 2015

This study presents a validated, porous graphitic carbon stationary phase-based LC-MS/MS method f... more This study presents a validated, porous graphitic carbon stationary phase-based LC-MS/MS method for the identification and quantification of lacto-N-biose (LNB) and N-acetyllactosamine (LacNAc). These compounds are the major building blocks of human milk oligosaccharides, however the presence of their unbound form in human milk has not been examined so far. The separation of these highly related structures in their alditol form was accomplished by a gradient LC method and multiple reaction monitoring (MRM) analysis after appropriate sample preparation including size-exclusion chromatography and solid-phase extraction. Baseline separation of the components provides the selectivity for the method. Validation was performed according to the European Medicines Agency (EMA) Guidelines and the method was found to be precise and accurate. Using our developed and validated method we were able to identify and quantify both saccharides in human milk for the first time. Based on our results the...

Molecules, 2021

In order to better understand the chiral recognition mechanisms of positively charged cyclodextri... more In order to better understand the chiral recognition mechanisms of positively charged cyclodextrin (CD) derivatives, the synthesis, the pKa determination by 1H nuclear magnetic resonance (NMR)-pH titration and a comparative chiral capillary electrophoretic (CE) study were performed with two series of mono-substituted cationic single isomer CDs. The first series of selectors were mono-(6-N-pyrrolidine-6-deoxy)-β-CD (PYR-β-CD), mono-(6-N-piperidine-6-deoxy)-β-CD (PIP-β-CD), mono-(6-N-morpholine-6-deoxy)-β-CD (MO-β-CD) and mono-(6-N-piperazine-6-deoxy)-β-CD (PIPA-β-CD), carrying a pH-adjustable moiety at the narrower rim of the cavity, while the second set represented by their quaternarized, permanently cationic counterparts: mono-(6-N-(N-methyl-pyrrolidine)-6-deoxy)-β-CD (MePYR-β-CD), mono-(6-N-(N-methyl-piperidine)-6-deoxy)-β-CD (MePIP-β-CD), mono-(6-N-(N-methyl-morpholine)-6-deoxy)-β-CD (MeMO-β-CD) and mono-(6-N-(4,4-N,N-dimethyl-piperazine)-β-CD (diMePIPA-β-CD). Based on pH-depende...

Beilstein Journal of Organic Chemistry, 2016

This work focuses on the preparation and application of supramolecular structures based on mono-c... more This work focuses on the preparation and application of supramolecular structures based on mono-cinnamyl-α-cyclodextrins (Cin-α-CD). Pure regioisomers of Cin-α-CD having the cinnamyl moiety at the 2-O- or at the 3-O-position, respectively, were prepared, characterized and applied in capillary electrophoresis as additives to the background electrolyte. These new monomer units with a potential to self-organize into supramolecular structures were synthesized via a straightforward one-step synthetic procedure and purified using preparative reversed-phase chromatography allowing a large scale separation of the regioisomers. The ability of the monomers to self-assemble was proved by various methods including NMR spectroscopy and dynamic light scattering (DLS). The light scattering experiments showed that the monomer units have distinguishable ability to form supramolecular structures in different solvents and the size distribution of the aggregates in water can be easily modulated using d...

Journal of Pharmaceutical and Biomedical Analysis, 2021

The highly anionic synthetic pentasaccharide fondaparinux (FDPX)-representing the antithrombin bi... more The highly anionic synthetic pentasaccharide fondaparinux (FDPX)-representing the antithrombin binding sequence of heparin-is in clinical use as a potent anticoagulant. Contrary to the unfractionated heparin, FDPX lacks potent antidote completely reversing its anticoagulant activity, therefore it is of great importance to identify new structures exhibiting strong intermolecular interactions towards FDPX. The polycationic heptakis(6-amino-6-deoxy)-beta-cyclodextrin (NH 2-␤-CD) can serve as an excellent model compound to mimic these interactions between the oppositely charged oligosaccharides. Herein, extensive NMR spectroscopic and nano-electrospray ionization mass spectrometric (nESI-MS) studies were conducted to understand the molecular-level interactions in the FDPX-NH 2-␤-CD systems. NMR experiments were performed at pD 7.4 and 2.0. Job's method of continuous variation and 1 H NMR titration experiments suggested the formation of FDPX•NH 2-␤-CD complex at pD 7.4, while the presence of multiple complexes was assumed at pD 2.0. Stability constants were determined by separate 1 H NMR titrations, yielding log ˇ1 1 =3.65 ± 0.02 at pD 7.4, while log ˇ1 1 ≥ 4.9 value suggested a high-affinity system at pD 2.0. 2D NOESY NMR studies indicated spatial proximities between the anomeric resonance ␣-l-iduronic acid residue and the cyclodextrin's methylene unit in the proximity of the cationic amino function. Acidic degradation of FDPX was investigated by NMR and MS for the first time in detail confirming that desulfation occurs involving one to two sulfate moieties. The desulfation of FDPX was inhibited by the cationic cyclodextrin in the case of equimolar ratio at pD 2.0. This is the first report on the stabilizing effect of cyclodextrin complexation on heparin degradation.

Natural Product Communications, 2016

In Jurinea mollis fruit, the dibenzylbutyrolactone-type lignan glycoside arctiin and its aglycone... more In Jurinea mollis fruit, the dibenzylbutyrolactone-type lignan glycoside arctiin and its aglycone arctigenin were determined for the first time using a combination of optimized enzymatic treatment and complementary spectrometric (HPLC-MS, GC-MS) and spectroscopic (CD and NMR) methods. Analysis of separated fruit parts, i.e., the fruit wall and embryo, demonstrated the specific accumulation of arctiin, since it was exclusively found in the embryo. Arctiin in the embryo samples (71.5 mg/g) was found to be quantitatively converted into arctigenin (50.7 mg/g) by endogenous enzymatic hydrolysis, resulting in one of the highest arctigenin-containing plant tissues reported to date and allowing the selective isolation of arctigenin by our recently reported three-step isolation method. The absolute configuration of the isolated arctigenin was determined to be (-)-(8 R,8′ R). Conformational analysis of arctigenin was also performed, resulting in three major low energy conformations.

ELECTROPHORESIS, 2017

List of abbreviations: 4-methylethcathinone (4-MEC), background electrolyte (BGE), capillary elec... more List of abbreviations: 4-methylethcathinone (4-MEC), background electrolyte (BGE), capillary electrophoresis (CE), chiral capillary electrophoresis (CCE), cyclodextrin (CD), dapoxetine (dpx), desmethyl-dapoxetine (desmethyl-dpx), didesmethyl-dapoxetine (didesmethyl-dpx), dimethyl sulfoxide (DMSO), diode array detector (DAD), enantioresolution (R S), electroosmotic flow (EOF), enantiomer migration order (EMO), heptakis-(2,3-di-O-methyl-6-O-carboxymethyl)β-cyclodextrin (HDMCM), heptakis-(2,3-di-O-methyl-6-O-sulfated)-β-cyclodextrin (HDMS), inside diameter (id), methanol (MeOH), methylenedioxypyrovalerone (MDPV), non-aqueous capillary electrophoresis (NACE), refractive index (RI), single-isomer cyclodextrin derivative (SID), tert-butyldimethylsilyl chloride (TBDMSiCl), tetrahydrofuran (THF), tris(hydroxymethyl)aminomethane (Tris).

Journal of Pharmaceutical and Biomedical Analysis, 2016

Restharrow root has been used in traditional medicine for thousands of years; however, the active... more Restharrow root has been used in traditional medicine for thousands of years; however, the active ingredients responsible for the diuretic effect are still unknown. Previous studies have proved that the root extract contains isoflavonoids, however only few derivatives were identified, mostly relying on retention times or UV data. The aim of our work was to perform a detailed structural characterization of the complete isoflavonoid profile in the aqueous-methanolic extract of Ononis spinosa root by high-performance liquid chromatography coupled with electrospray ionization accurate-mass quadrupole time-of-flight and tandem mass spectrometry in positive ionization mode (HPLC-ESI-QTOF-MS, HPLC-ESI-MS/MS) and nuclear magnetic resonance spectroscopy (NMR). On the basis of the accurate masses and fragmentation patterns isoflavones (formononetin, calycosin and pseudobaptigenin) and pterocarpans (maackiain and medicarpin) were identified. Two further dihydroisoflavone aglycones, namely onogenin and sativanone and a unique glucoside were isolated and their structures were elucidated by NMR experiments. Calycosin, onogenin and sativanone were detected in this plant for the first time. In contrast to previous works, the presence of biochanin A could not be confirmed, however its regioisomer calycosin and its derivatives were identified. Similarly, neither tectorigenin derivatives could be detected, however the isobar compound sativanone and its various glucosides were elucidated. The presence of genistein and daidzein could not be confirmed in the extract. Fragmentation pathways for onogenin and sativanone are presented. In the aqueous-methanolic extract 9 glucosides, 6 minor and 8 major glucoside malonates, 4 glucoside acetates and 7 aglycones were found. In total, 34 compounds were successfully identified.