Low-temperature 1H-NMR spectroscopic study of doxorubicin influence on the hydrated properties of nanosilica modified by DNA

Mathematical modeling and optimization technique of anticancer antibiotic adsorption onto carbon nanocarriers

This study employs a combination of mathematical derivation and optimization technique to investigate the adsorption of drug molecules on nanocarriers. Specifically, the chemotherapy drugs, fluorouracil, proflavine, and methylene blue, are non-covalently bonded with either a flat graphene sheet or a spherical C 60 fullerene. Mathematical expressions for the interaction energy between an atom and graphene, as well as between an atom and C 60 fullerene, are derived. Subsequently, a discrete summation is evaluated for all atoms on the drug molecule utilizing the U-NSGA-III algorithm. The stable configurations' three-dimensional architectures are presented, accompanied by numerical values for crucial parameters. The results indicate that the nanocarrier's structure effectively accommodates the atoms on the drug's carbon planes. The three drug types' molecules disperse across the graphene surface, whereas only fluorouracil spreads on the C 60 surface; proflavine and methylene blue stack vertically to form a layer. Furthermore, all atomic positions of equilibrium configurations for all systems are obtained. This hybrid method, integrating analytical expressions and an optimization process, significantly reduces computational time, representing an initial step in studying the binding of drug molecules on nanocarriers.

A Computational Study of the Immobilization of New 5-Nitroisatine Derivatives with the Use of C60-Based Functionalized Nanocarriers

Isatin-based compounds are a large group of drugs used as competitive inhibitors of ATP. The 5-nitroisatin derivatives studied in this work are inhibitors of the CDK2 enzyme, which can be used in the development of new anti-cancer therapies. One of the basic activities that often allows for an increase in biological activity while reducing the undesirable effects associated with the toxicity of medicinal substances is immobilization based on carriers. In this work, fifty nanocarriers derived from C60 fullerene, containing a bound phenyl ring on their surfaces, were used in the process of the immobilization of isatin derivatives. Based on flexible docking methods, the binding capacities of the drugs under consideration were determined using a wide range of nanocarriers containing symmetric and asymmetric modifications of the phenyl ring, providing various types of interactions. Based on the data collected for each of the tested drugs, including the binding affinity and the structure and stability of complexes, the best candidates were selected in terms of the type of substituent that modified the nanoparticle and its location. Among the systems with the highest affinity are the dominant complexes created by functionalized fullerenes containing substituents with a symmetrical location, such as R2-R6 and R3-R5. Based on the collected data, nanocarriers with a high potential for immobilization and use in the development of targeted therapies were selected for each of the tested drugs.

The Immobilization of Oxindole Derivatives Using New Designed Functionalized C60 Nanomolecules

Indirubin and its analogs such as oxindole derivatives are well known as competitive inhibitors of cyclin-dependent kinase 2 (CDK2) and play an important role in the creation of therapies in many cancer diseases. Recent research, in order to increase efficiency, is aimed at creating targeted therapy, which is often based on the immobilization of drugs on the surface of nanocarriers. In this work, two oxindole derivatives were used to test the binding capabilities of newly in silico designed C60 fullerene derivatives. Seventy functionalized nanostructures were created by the addition of amino acid substituents to the single phenyl ring attached to the fullerene surface. Realized calculations, based on flexible docking methods, allowed for obtaining energetic characteristics and structural aspects of complexes created by nanomolecules with considered ligands. Analysis of obtained complexes shows that symmetric substitution to position R3 and R5 allows obtaining fullerene derivatives exhibiting the highest binding capabilities, while the lowest ones are the effect of asymmetric substitution (R2; R4). Obtained values clearly allowed to select a group of substituents and substitution sites that provide the most stable complexes which can be used to create new nanocarriers for the group of drugs under consideration.

The Immobilization of ChEMBL474807 Molecules Using Different Classes of Nanostructures

Indirubin derivatives and analogues are a large group of compounds which are widely and successfully used in treatment of many cancer diseases. In particular, the ChEMBL474807 molecule, which has confirmed inhibiting abilities against CDK2 and GSK3B enzymes, can be included in this group. The immobilization of inhibitors with the use of nanocarriers is an often used strategy in creation of targeted therapies. Evaluations were made of the possibility of immobilizing ligand molecules on different types of nanocarrier, such as carbon nanotubes (CNT), functionalized fullerene C60 derivatives (FF_X), and functionalized cube rhombellanes, via the use of docking methods. All results were compared with a reference system, namely C60 fullerene. The realized calculations allowed indication of a group of compounds that exhibited significant binding affinity relative to the ligand molecule. Obtained data shows that structural modifications, such as those related to the addition of functional groups or changes of structure symmetry, realized in particular types of considered nanostructures, can contribute to increases of their binding capabilities. The analysis of all obtained nano complexes clearly shows that the dominant role in stabilization of such systems is played by stacking and hydrophobic interactions. The realized research allowed identification of potential nanostructures that, together with the ChEMBL474807 molecule, enable the creation of targeted therapy.

Investigation of the Inhibition Potential of New Oxindole Derivatives and Assessment of Their Usefulness for Targeted Therapy

Oxindole derivatives are a large group of compounds that can play the role of Adenosine triphosphate (ATP) competitive inhibitors. The possibility of modification of such compounds by addition of active groups to both cyclic systems of oxindole allows the obtaining of derivatives showing significant affinity toward cyclin-dependent kinase (CDK) proteins. Overexpression of that enzyme is observed in the case of most cancers. The discovery of new efficient inhibitors, which could be used in the development of targeted therapies, is one of the current goals setting trends in recent research. In this research, an oxindole molecular core was used, which was modified by the addition of different substituents to both side chains. The realized procedure allowed the creation of a set of oxindole derivatives characterized by binding affinity values and molecular descriptors evaluated during docking procedures and QSAR calculations. The most promising structures characterized by best sets of parameters were used during the molecular dynamics stage. The analysis of structural and energetic properties of systems obtained during this stage of computation gives an indication of inhibitors creating the most stable complexes, characterized by the highest affinity. During this stage, two structures were selected, where affinity towards potential nanocarriers was evaluated. Realized calculations confirmed a significant role of stacking interactions in the stabilization of ligand complexes with fullerene molecules. Obtained data indicates that complexes of oxindole derivatives and considered nanocarriers exhibit significant potential in the creation of immobilized drugs, and can be used in the development of targeted therapies.

The Immobilization of Oxindole Derivatives with Use of Cube Rhombellane Homeomorphs

A key aspect of modern drug research is the development of delivery methods that ensure the possibility of implementing targeted therapy for a specific biological target. The use of nanocarriers enables to achieve this objective, also allowing to reduce the toxicity of used substances and often extending their bioavailability. Through the application of docking methods, the possibility of using cube rhombellanes as potential carriers for two oxindole derivatives was analyzed. In the studies, compounds identified as inhibitors of the CDK2 enzyme and a set of nanostructures proposed by the Topo Cluj Group were used. The popular fullerene molecule C60 was used as the reference system. The estimated binding affinities and structures of obtained complexes show that use of functionalized cube rhombellanes containing hydrogen bond donors and acceptors in their external molecular shell significantly increases ligand affinity toward considered nanocariers, compared to classic fullerenes. The presented values also allow to state that an important factor determining the mutual affinity of the tested ligands and nanostructures is the symmetry of the analyzed nanocarriers and its influence on the distribution of binding groups (aromatic systems, donors and acceptors of hydrogen bonds) on the surface of nanoparticles.

Fullerene as a doxorubicin nanotransporter for targeted breast cancer therapy: Capillary electrophoresis analysis

The clinical use of doxorubicin (DOX) is limited by dose-related cardiomyopathy, which becomes more prevalent with increasing cumulative doses of the drug. Complexes of fullerene with DOX were designed and studied using biophysical methods. The ability of DOX to release from fullerene at different pHs was analyzed. It has been shown that the size of the fullerene-DOX complexes was ∼280 nm. The zeta potential for fullerene was -30 mV, for DOX -8 mV, and for fullerene-DOX conjugates -24 mV. Drug release was studied by CE with LIF detection. When fullerene-DOX conjugates were separated in a pH 7.5 buffer, 43% of all DOX signals were derived from free DOX, with the signal increasing as pH decreased. At pH 5.25, all DOX had been released and 100% of the signal was derived from free DOX. The release of DOX from complexes with fullerene at lower pH can be used in targeted antineoplastic therapy, resulting in lower toxicity for less acidic non-target tissue.