Background/Objectives: Rivaroxaban, an oral anticoagulant, shows poor aqueous solubility, posing significant challenges to its bioavailability and therapeutic efficiency. The present study investigates the improvement of rivaroxaban's solubility through the formation of different inclusion complexes with three cyclodextrin derivatives, such as β-cyclodextrin (β-CD), methyl-β-cyclodextrin (Me-β-CD), and hydroxypropyl-β-cyclodextrin (HP-β-CD) prepared by lyophilization in order to stabilize the complexes and improve dissolution characteristics of rivaroxaban. Methods: The physicochemical properties of the individual compounds and the three lyophilized complexes were analysed using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Results: FTIR spectra confirmed the formation of non-covalent interactions between rivaroxaban and the cyclodextrins, suggesting successful encapsulation into cyclodextrin cavity. SEM images revealed a significant morphological transformation from the crystalline structure of pure rivaroxaban and cyclodextrins morphologies to a more porous and amorphous matrix in all lyophilized complexes. XRD patterns indicated a noticeable reduction in drug crystallinity, supporting enhanced potential of the drug solubility. TGA analysis demonstrated improved thermal stability in the inclusion complexes compared to the individual drug and cyclodextrins. Pharmacotechnical evaluation revealed that the obtained formulations (by comparison with physical mixtures formulations) possessed favorable bulk and tapped density values, suitable compressibility index, and good flow properties, making all suitable for direct compression into solid dosage forms. Conclusions: The improved cyclodextrins formulation characteristics, combined with enhanced dissolution profiles of rivaroxaban comparable to commercial Xarelto® 10 mg, highlight the potential of both cyclodextrin inclusion and lyophilization technique as synergistic strategies for enhancing the solubility and drug release of rivaroxaban.
- Publication type
- Journal Article MeSH
Anionic boron cluster compounds have recently made their way into many areas including medicinal chemistry and sensors due to favorable physical-chemical properties and their various biological activity. Notwithstanding the inherent chirality of these compounds, the exploration of the properties and activity of individual enantiomers remains uncharted territory. The permanent delocalized negative charge enables the electrophoretic mobility of these compounds. Thus, chiral electrophoresis, characterized by minimal consumption of chemicals and a sample, emerges as a promising candidate for a reliable quality control tool. The primary attempts in aqueous electrolytes showed some difficulties related to the limited solubility of these analytes. This study meticulously investigates the electrophoretic behavior and chiral separation of anionic [7,8-nido-C2B9H11]- and cobalt bis(dicarbollide)(1-) derivatives using a methanolic non-aqueous electrolyte with numerous derivatives of cyclodextrins. Randomly substituted hydroxypropyl-β-, methyl-β-, and hydroxypropyl-γ-cyclodextrins were identified as the most effective chiral selectors. The chiral separations delineated herein surpass previously published results in capillary electrophoresis in terms of resolution, peak shape, and the number of theoretical plates. Furthermore, the application of (2-hydroxy-3-N,N,N-trimethylamino)propylated β-cyclodextrin in non-aqueous environment resulted in the chiral separation of seven recently synthesized amino cobalt bis(dicarbollide)(1-) derivatives; thereby, reinforcing the extensive applicability of the developed methodology for different structural types of anionic cobalt bis(dicarbollides)(1-). These results qualify non-aqueous electrophoresis as a valuable tool for the enantiomeric purity control of anionic boron cluster compounds with respect to their further use in various areas.
- Publication type
- Journal Article MeSH
Léčivé přípravky pro intravenózní podání často obsahují kromě farmakologicky účinné látky i pomocné látky, které zajišťují rozpustnost, stabilitu a správné pH léčiva. Tradičně se předpokládá, že pomocné látky jsou biologicky inertní, avšak tento předpoklad není vždy naplněn. Některé pomocné látky mohou způsobovat hypersenzitivní reakce, indukovanou orgánovou toxicitu, diskomfort při aplikaci či vykazovat vlastní biologické účinky. Regulace těchto látek se liší podle jejich známých účinků, a tak ne vždy je kvantitativ- ní obsah těchto látek specifikován. Tento článek se zaměřuje na tři často používané pomocné látky v intravenózních lékových formách – propylenglykol, polysorbát 80 a sulfobutylether-β-cyklodextrin (SBECD). V článku analyzujeme farmakologické profily těchto látek, jejich potenciální toxicitu a možnosti prevence nežádoucích účinků, s důrazem na jejich použití u kriticky nemocných dospělých pacientů, kde intravenózní podání léků je často jedinou možností. Tento přístup je zásadní pro minimalizaci rizik spojených s použitím těchto pomocných látek v intenzivní medicíně.
Medicinal products for intravenous administration often contain excipients, in addition to the pharmacologically active substance, that ensure the solubility, stability and correct pH of the drug. Excipients are assumed to be biologically inert, but this assumption is not always met. Some excipients may cause hypersensitivity reactions, organ toxicity, discomfort on administration or show own biological effects The regulatory framework for these substances varies according to their known effects, thus the quantitative content of these substances is not always compulsory to be specified. This article focuses on three frequently used excipients in intravenous drug dosage forms - propylene glycol, polysorbate 80 and sulfobutyl ether-β-cyclodextrin (SBECD). In this article, we discuss the pharmacological profiles of these agents, their potential toxicity, and options for preventing adverse effects, with an emphasis on their use in critically ill adults where intravenous drug administration is often the only option. This approach is essential to minimise the risks associated with the use of these excipients in critically ill.
- Keywords
- sulfobutylether-β-cyklodextrin,
- MeSH
- Administration, Intravenous methods MeSH
- Humans MeSH
- Drug-Related Side Effects and Adverse Reactions * drug therapy classification MeSH
- Polysorbates pharmacology classification metabolism MeSH
- Excipients * pharmacology adverse effects MeSH
- Propylene Glycol pharmacology metabolism MeSH
- Check Tag
- Humans MeSH
- Publication type
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
Among different substance classes, New Psychoactive Substances (NPS) comprise chiral amphetamines for stimulant and empathic effects. There is little knowledge in terms of clinical studies about possibly different effects of the two enantiomers of novel amphetamine derivatives. For this reason, there is a big demand for enantioseparation method development of this new substance class. Regarding gas chromatography, cyclodextrins proved to be effective for enantioseparation of NPS. In our attempt, an Astec® ChiraldexTM G-PN column containing 2,6-di-O-pentyl-3-propionyl-γ-cyclodextrin and a LipodexTM D column containing heptakis-(2,6-di-O-pentyl-O-acetyl)-β-cyclodextrin as chiral selector served as stationary phases in a Shimadzu GCMS-QP2010 SE system. Because of the special coating, maximum temperature is limited to 200 °C isothermal or 220 °C in programmed mode. To ensure detection, trifluoroacetic anhydride (TFAA) was used to increase sample volatility.1 As a result, 35 amphetamines were tested as their TFAA-derivatives. A screening method with a temperature gradient from 140 °C to 200 °C at a heating ramp of 1 °C per minute and final time of 5 min, showed baseline separation for seven and partial separations for 16 trifluoro acetylated amphetamines using the ChiraldexTM G-PN column. Six baseline and nine partial separations were observed with the LipodexTM D column, respectively.
Cyclin-dependent kinases (CDKs) play an important role in the cell-division cycle. Synthetic inhibitors of CDKs are based on 2,6,9-trisubstituted purines and are developed as potential anticancer drugs; however, they have low solubility in water. In this study, we proved that the pharmaco-chemical properties of purine-based inhibitors can be improved by appropriate substitution with the adamantane moiety. We prepared ten new purine derivatives with adamantane skeletons that were linked at position 6 using phenylene spacers of variable geometry and polarity. We demonstrated that the adamantane skeleton does not compromise the biological activity, and some of the new purines displayed even higher inhibition activity towards CDK2/cyclin E than the parental compounds. These findings were supported by a docking study, which showed an adamantane scaffold inside the binding pocket participating in the complex stabilisation with non-polar interactions. In addition, we demonstrated that β-cyclodextrin (CD) increases the drug's solubility in water, although this is at the cost of reducing the biochemical and cellular effect. Most likely, the drug concentration, which is necessary for target engagement, was decreased by competitive drug binding within the complex with β-CD.
- MeSH
- Adamantane chemistry MeSH
- beta-Cyclodextrins chemistry MeSH
- K562 Cells MeSH
- Cyclin-Dependent Kinase 2 antagonists & inhibitors MeSH
- Protein Kinase Inhibitors pharmacology MeSH
- Humans MeSH
- MCF-7 Cells MeSH
- Antineoplastic Agents chemistry pharmacology MeSH
- Purines chemistry MeSH
- Structure-Activity Relationship MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Boron cluster compounds are extensively studied due to their possible use in medicinal chemistry, mainly in the boron neutron capture anticancer therapy and as new innovative pharmacophores. Concerning this research, the chiral separations of exceptionally stable anionic 7,8-dicarba-nido-undecaborate(1-) and metal bis(dicarbollide(1-) derivatives with asymmetric substitutions remain the unsolved challenge of the chiral chromatography nowadays. Although the successful enantioseparation of some anionic 7,8-dicarba-nido-undecaborate(1-) ion derivatives were achieved in CZE with native β-cyclodextrins, it has not been observed with HPLC, yet. This study aimed to systematically investigate the enantioseparation of selected compounds in HPLC using native β-cyclodextrin and brominated β-cyclodextrin. The findings revealed positively charged strong adsorption sites on a stationary phase, identified as the cationic metal impurities in the silica-gel backbone. All the anionic species under the study were at least partially enantioseparated when a chelating agent blocked these cationic sites. Consequently, the first-ever HPLC enantioseparations of the 7,8-dicarba-nido-undecaborates(1-) were achieved. The brominated β-cyclodextrin seemed to be a better chiral selector for separation of these species, whereas the native β-cyclodextrin separated the anionic cobalt bis(dicarbollide(1-). The results of this study bring new information concerning the chiral separation of anionic boron clusters and might be used in the chiral method development process on other chiral selectors. Furthermore, the possibility of chiral separation of these species could influence the ongoing research areas of anionic boron clusters.
- MeSH
- Anions MeSH
- Cyclodextrins * MeSH
- Cations MeSH
- Boron Compounds * MeSH
- Stereoisomerism MeSH
- Chromatography, High Pressure Liquid MeSH
- Publication type
- Journal Article MeSH
The biological electron transfer reactions play an important role in the bioactivity of drugs; thus, the knowledge of their electrochemical behavior is crucial. The formation of radicals during oxidation or reduction, the presence of short-living intermediates, the determination of reaction mechanisms involving electron and proton transfers, all contribute to the comprehension of drug activities and the determination of their mode of action and their metabolites. In addition, if a drug is encapsulated in the cyclodextrin cavity, its electrochemical properties can change compared to a free drug molecule. Here we describe the combination of cyclic voltammetry, UV-Vis spectroelectrochemistry, GC-MS, HPLC-DAD, and HPLC-MS/MS as techniques for evaluating the oxidation mechanism of a drug encapsulated in the cavity of a cyclodextrin. The cavity of cyclodextrin plays a significant role in increasing the stability of the encapsulated products; therefore the identification of oxidation intermediates as semiquinone and benzofuranone derivatives of quercetin is possible in these conditions. The differences in oxidation potentials of the bioactive flavonol quercetin and its cyclodextrin complex relating to its antioxidant activity and the oxidation mechanism are herein discussed.
In this study, the apparent binding constants and limiting mobilities of the multiply charged complexes of the Δ- and Λ-enantiomers of Ru(II)- and Fe(II)-polypyridyl associates ([Ru(2,2'-bipyridine)3 ]2+ , [Ru(1,10-phenanthroline)3 ]2+ , and [Fe(1,10-phenanthroline)3 ]2+ ) with single-isomer 2,3-diacetylated-6-sulfated-cyclodextrins (CDs) (12Ac-6S-α-CD, 14Ac-7S-β-CD, and 16Ac-8S-γ-CD) were determined by ACE using uncorrected and ionic strength corrected actual mobilities of the species involved. Two limiting models were tested for the ionic strength correction of the actual mobilities based on an empirical relation for the ionic strength correction of multivalent ionic species. In model 1, the nominal values of the charge numbers (zS,nom ) and analytical concentrations (cS,nom ) of the above CD selectors in the BGEs were applied for calculation of the BGE ionic strength, as usual. In model 2, the CD selectors were considered as singly charged species (zS = -1) with |zS,nom |-times higher concentrations in the BGE than their analytical concentrations (cS = |zS,nom | × cS,nom ) in the calculation of the BGE ionic strength. In all three cases-with uncorrected actual mobilities as well as with actual mobilities corrected according to the two limiting models-the measured effective mobilities of the above enantiomers fit well the theoretical curves of their mobility dependences on the CD selectors concentrations in the BGE, with high average coefficients of determination (R2 = 0.9890-0.9995). Nevertheless, the best physico-chemically meaningful values of the apparent binding constants and the limiting mobilities of the enantiomer-CDs complexes with low RSDs were obtained using the actual mobilities of the species involved corrected according to model 2.
We discuss several possible phenomena in electrophoretic systems with complexing agents present in the background electrolyte. In our previous work, we extended the linear theory of electromigration with the first-order nonlinear term, which originally applied to acid-base equilibria only, by generalizing it to any fast chemical equilibria. This extension provides us with a fresh insight into the well-established technique of elecktrokinetic chromatography (EKC). We combine mathematical analysis of the generalized model with its solution by means of the new version of our software PeakMaster 6, and experimental data. We re-examine the fundamental equations by Wren and Rowe and Tiselius in the frame of the generalized linear theory of electromigration. Besides, we show that selector concentration can increase inside the interacting-analyte zone due to its complexation with the analyte, which contradicts the generally accepted idea of a consumption of a portion of the selector inside the zone. Next, we focus our discussion on interacting buffers (i.e., buffer constituents that form a complex with the selector). We demonstrate how such side-interaction of the selector with another buffer constituent can influence measuring analyte-selector interactions. Finally, we describe occurrence and mobilities of system peaks in these EKC systems. We investigate systems with fully charged analytes and neutral cyclodextrins as selectors. Although the theory is not limited in terms of the charge and/or the degree of (de)protonation of any constituent, this setup allows us to find analytical solutions to generalized model under approximate, yet realistic, conditions and to demonstrate all important phenomena that may occur in EKC systems. An occurrence of system peaks in a system with fully charged selector is also investigated.
The optimization of sustainable protocols for reductive amination has been a lingering challenge in green synthesis. In this context, a comparative study of different metal-loaded cross-linked cyclodextrins (CDs) were examined for the microwave (MW)-assisted reductive amination of aldehydes and ketones using either H2 or formic acid as a hydrogen source. The Pd/Cu heterogeneous nanocatalyst based on Pd (II) and Cu (I) salts embedded in a β-CD network was the most efficient in terms of yield and selectivity attained. In addition, the polymeric cross-linking avoided metal leaching, thus enhancing the process sustainability; good yields were realized using benzylamine under H2. These interesting findings were then applied to the MW-assisted one-pot synthesis of secondary amines via a tandem reductive amination of benzaldehyde with nitroaromatics under H2 pressure. The formation of a CuxPdy alloy under reaction conditions was discerned, and a synergic effect due to the cooperation between Cu and Pd has been hypothesized. During the reaction, the system worked as a bifunctional nanocatalyst wherein the Pd sites facilitate the reduction of nitro compounds, while the Cu species promote the subsequent imine hydrogenation affording structurally diverse secondary amines with high yields.
- MeSH
- Amination MeSH
- Amines chemistry MeSH
- Benzaldehydes chemistry MeSH
- beta-Cyclodextrins chemistry MeSH
- Cyclodextrins chemistry MeSH
- Catalysis MeSH
- Metals chemistry MeSH
- Copper chemistry MeSH
- Microwaves * MeSH
- Nanoparticles chemistry MeSH
- Palladium chemistry MeSH
- Cross-Linking Reagents chemistry MeSH
- Publication type
- Journal Article MeSH
