Development of 5-fluorouracil/etoposide co-loaded electrospun nanofibrous scaffold for localized anti-melanoma therapy.

Nanofibrous scaffolds have emerged as promising candidates for localized drug delivery systems in the treatment of cutaneous cancers. In this study, we prepared an electrospun nanofibrous scaffold incorporating 5-fluorouracil (5-FU) and etoposide (ETP) for chemotherapy targeting melanoma cutaneous cancer. The scaffold was composed of polyvinyl alcohol (PVA) and chitosan (CS), prepared via the electrospinning process and loaded with the chemotherapeutic agents. We conducted relevant physicochemical characterizations, assessed cytotoxicity, and evaluated apoptosis against melanoma A375 cells. The prepared 5-FU/ETP co-loaded PVA/CS scaffold exhibited nanofibers (NFs) with an average diameter of 321 ± 61 nm, defect-free and homogenous morphology. FTIR spectroscopy confirmed successful incorporation of chemotherapeutics into the scaffold. Additionally, the scaffold demonstrated a hydrophilic surface, proper mechanical strength, high porosity, and efficient liquid absorption capacity. Notably, sustained and controlled drug release was observed from the nanofibrous scaffold. Furthermore, the scaffold significantly increased cytotoxicity (95%) and apoptosis (74%) in A375 melanoma cells. Consequently, the prepared 5-FU/ETP co-loaded PVA/CS nanofibrous scaffold holds promise as a valuable system for localized eradication of cutaneous melanoma tumors and mitigation of adverse drug reactions associated with chemotherapy.

Multi-Sensitive Au NCs/5-FU@Carr-LA Composite Hydrogels for Targeted Multimodal Anti-Tumor Therapy.

Multifunctional targeted drug delivery systems have been explored as a novel cancer treatment strategy to overcome limitations of traditional chemotherapy. The combination of photodynamic therapy and chemotherapy has been shown to enhance efficacy, but the phototoxicity of traditional photosensitizers is a challenge. In this study, we prepared a multi-sensitive composite hydrogel containing gold nanoclusters (Au NCs) and the temperature-sensitive antitumor drug 5-fluorourac il (5-FU) using carboxymethyl cellulose (Carr) as a dual-functional template. Au NCs were synthesized using sodium borohydride as a reducing agent and potassium as a promoter. The resulting Au NCs were embedded in the Carr hydrogel, which was then conjugated with lactobionic acid (LA) as a targeting ligand. The resulting Au NCs/5-FU@Carr-LA composite hydrogel was used for synergistic photodynamic therapy (PDT), photothermal therapy (PTT), and chemotherapy. Au NCs/5-FU@Carr-LA releases the drug faster at pH 5.0 due to the acid sensitivity of the Carr polymer chain. In addition, at 50 °C, the release rate of Au NCs/5-FU@Carr-LA is 78.2%, indicating that the higher temperature generated by the photothermal effect is conducive to the degradation of Carr polymer chains. The Carr hydrogel stabilized the Au NCs and acted as a matrix for drug loading, and the LA ligand facilitated targeted delivery to tumor cells. The composite hydrogel exhibited excellent biocompatibility and synergistic antitumor efficacy, as demonstrated by in vitro and in vivo experiments. In addition, the hydrogel had thermal imaging capabilities, making it a promising multifunctional platform for targeted cancer therapy.

Structure and Characterization of Catanionic Complexes and Biocompatible Vesicles of N-Acyltaurine and Sarcosine Alkyl Ester: Encapsulation and Release Studies with 5-Fluorouracil.

Hydrated dispersions containing equimolar mixtures of cationic and anionic amphiphiles, referred to as catanionic systems, exhibit synergistic physicochemical properties, and mixing single-chain cationic and anionic lipids can lead to the spontaneous formation of vesicles as well as other phase structures. In the present work, we have characterized two catanionic systems prepared by mixing N-acyltaurines (NATs) and sarcosine alkyl esters (SAEs) bearing 11 and 12 C atoms in the acyl/alkyl chains. Turbidimetric and isothermal titration calorimetric studies revealed that both NATs form equimolar complexes with SAEs having matching acyl/alkyl chains. The three-dimensional structure of the sarcosine lauryl ester (lauryl sarcosinate, LS)-N-lauroyltaurine (NLT) equimolar complex has been determined by single-crystal X-ray diffraction. The LS-NLT equimolar complex is stabilized by electrostatic attraction and multiple hydrogen bonds, including classical, strong N-H···O hydrogen bonds as well as several C-H···O hydrogen bonds between the two amphiphiles. DSC studies showed that both equimolar complexes show single sharp phase transitions. Transmission electron microscopy and dynamic light scattering studies have demonstrated that the LS-NLT catanionic complex assemblies yield stable medium-sized vesicles (diameter 280-350 nm). These liposomes were disrupted at high pH, suggesting that the designed catanionic complexes can be used to develop base-labile drug delivery systems. In vitro studies with these catanionic liposomes showed efficient entrapment (73% loading) and release of the anticancer drug 5-fluorouracil in the physiologically relevant pH range of 6.0-8.0. The release rate was highest at pH 8.0, reaching about 78%, 90%, and 100% drug release at 2, 6, and 12 h, respectively. These observations indicate that LS-NLT catanionic vesicles will be useful for designing drug delivery systems, particularly for targeting organs such as the colon, which are inherently at basic pH.

Oral Saccharomyces cerevisiae-Guided Enzyme Prodrug Therapy Combined with Immunotherapy for the Treatment of Orthotopic Colorectal Cancer.

Colorectal cancer (CRC) is a major global health concern, and the development of effective treatment strategies is crucial. Enzyme prodrug therapy (EPT) shows promise in combating tumors but faces challenges in achieving sustained expression of therapeutic enzymes and optimal biological distribution. To address these issues, a fungi-triggered in situ chemotherapeutics generator (named as SC@CS@5-FC) was constructed via oral delivery of a prodrug (5-fluorocytosine, 5-FC) for the treatment of orthotopic colorectal tumor. When SC@CS@5-FC targets the tumor through tropism by Saccharomyces cerevisiae (SC), the chemotherapeutic generator could be degraded under abundant hyaluronidase (HAase) in the tumor microenvironment by an enzyme-responsive gate to release prodrug (5-FC). And nontoxic 5-FC was catalyzed to toxic chemotherapy drug 5-fluorouracil (5-FU) by cytosine deaminase (CD) of SC. Meanwhile, SC and zinc-coordinated chitosan nanoparticles could be used as immune adjuvants to activate antigen-presenting cells and further enhance the therapeutic effect. Our results demonstrated that SC@CS@5-FC could effectively inhibit tumor growth and prolong mouse survival in an orthotopic colorectal cancer model. This work utilizes living SC as a dynamotor and positioning system for the chemotherapeutic generator SC@CS@5-FC, providing a strategy for oral enzyme prodrug therapy for the treatment of orthotopic colorectal.

Efficient internalization of nano architectured 177Lu-hyaluronic acid@ zirconium-based metal-organic framework for the treatment of neuroblastoma: Unravelling toxicity, stability, radiolabelling and bio-distribution.

Zirconium-based metal-organic frameworks (UiO-66) have gained considerable attention owing to their versatile application. In the present research, UiO-66 was synthesized via a defect engineering approach, and its toxicity profile was explored. The synthesized nanomaterial was extensively characterized via spectroscopic methods such as FTIR and Raman spectroscopy, which confirmed the formation of the framework. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to determine the crystallinity, shape and size of the nanoformulations. Thermal gravimetric analysis, 1H NMR spectroscopy and Brunauer-Emmett-Teller (BET) surface area analysis were used to identify the differences between pristine and defective UiO-66. Furthermore, the synthesized MOF was exposed to various pH conditions, serum protein and DMEM. Drug loading and release studies were evaluated using 5-fluorouracil as a model anticancer drug. The synthesized MOFs were modified with hyaluronic acid via mussel-inspired polymerization to increase their uptake and stability. More importantly, the toxicity of the nanoformulation was investigated via various toxicity studies, such as hemolysis assays and cell viability assays, and was further supported by in vivo acute and subacute toxicity data obtained from Wistar rats. Radiolabelling and bio-distribution studies were also performed using 177Lu to explore the bio-distribution profile of UiO-66.

A thermoresponsive chitosan-based in situ gel formulation incorporated with 5-FU loaded nanoerythrosomes for fibrosarcoma local chemotherapy.

Local administration of drugs at tumor sites over an extended period of time shows potential as a promising approach for cancer treatment. In the present study, the temperature-induced phase transition of chitosan and poloxamer 407 is used to construct an injectable hydrogel encapsulating 5-FU-loaded nanoerythrosome (5-FU-NER-gel). The 5-FU-NERs were found to be spherical, measuring approximately 115 ± 20 nm in diameter and having a surface potential of -7.06 ± 0.4. The drug loading efficiency was approximately 40 %. In situ gel formation took place within 15 s when the gel was exposed to body temperature or subcutaneous injection. A sustained release profile was observed at pH 7.4 and 6.8, with a total 5-FU release of 76.57 ± 4.4 and 98.07 ± 6.31 in 24 h, respectively. MTT, Live/dead, and migration assays confirmed the cytocompatibility of the drug carrier and its effectiveness as a chemotherapeutic formulation. After in vivo antitumor assessment in a subcutaneous autograft model, it was demonstrated that tumor growth inhibition in 14 days was 90 %. Therefore, the obtained injectable chitosan-based hydrogel containing 5-FU-loaded nanoerythrosomes illustrated promising potential as a candidate for local and enhanced delivery of chemotherapeutics at the tumor site.

Hierarchically Micro-, Meso-, and Macro-Porous MOF Nanosystems for Localized Cross-Scale Dual-Biomolecule Loading and Guest-Carrier Cooperative Anticancer Therapy.

Mass transfer of bulky molecules, e.g., bioenzymes, particularly for cross-scale multibiomolecules, imposes serious challenges for microporous metal-organic frameworks (MOFs). Here, we create a hierarchically porous MOF heterostructure featuring highly region-ordered micro-, meso-, and macro-pores by growing a microporous ZIF-8 shell onto a hollow Prussian blue core through an epitaxial growth strategy. This allows for localized loading of large bioenzyme glucose oxidase (GOx) and small drug 5-fluorouracil (5-FU) within specific pores simultaneously and triggers unique guest-carrier cooperative anticancer capabilities. The stable ZIF-8 outer layer effectively blocks the core pores, preventing the undesired leakage of GOx into normal tissues. The acidity-induced ZIF-8 degradation gradually releases Zn2+ and loaded 5-FU for chemotherapy under acidic tumor microenvironments. With the loss of the shielding effect of the ZIF-8 coating, the released GOx depletes intratumoral glucose (Glu) for starvation therapy. Notably, an accelerated cascade reaction occurs between ZIF-8 decomposition and GOx release, facilitated by the modulator factor of Glu. This culminates in the realization of synergistic cancer therapy, as comprehensively demonstrated by in vitro and in vivo experiments, as well as transcriptome sequencing analyses. Our work not only introduces a hierarchically porous MOF heterostructure with highly region-ordered pores but also provides a perspective for guest-carrier cooperative anticancer therapy.

Magnetic particles with polymeric shells bearing lithocholic and folic acid moieties: Nano-warriors to fight colon cancer.

In the study, we aimed to investigate the activity of nanoformulations containing 5-fluorouracil and polymer-magnetic hybrids bearing membrane-penetrating and ligand-receptor-recognizing agents against colorectal cancer cells. The formation and characterization of iron oxide particles covered with polymeric shells comprising lithocholic acid and folic acid moieties are presented. The efficiency of nanoformulations combined by the simple mixing of low doses of 5-fluorouracil with the obtained hybrids was demonstrated against DLD-1 and HT-29 colon cancer cells. The most pronounced cytotoxic potential against HT-29 cells was observed in the cases of particles based on block and randomly arranged copolymers functionalized by FA motifs with depletion of viable cells by approximately 50 % compared to control cells and cells treated by 5-FU applied in free form. In the case of the DLD-1 cell line, the percentage of viable DLD-1 cells decreased by about 30 to 40% after treatment with the block and randomly arranged copolymer decorated by FA-moiety, when compared to 5-FU at the free form and the untreated control. The induction of apoptosis associated with PS-translocation was determined to be the main mechanism of their cytotoxic effects. Moreover, the safety profiles of the nanoformulations were established through hemolysis assay and the analysis of the viability of human colorectal fibroblasts. It was indicated that all tested nanoparticles met the compatibility requirements at the in vitro level. It should be emphasized that in many cases, there was a significant improvement in the compatibility of hybrids with the FA motif compared to non-functionalized hybrids with the addition of 5-FU. These findings suggest that the presence of FA might modulate the toxicity of chemotherapeutic agents.

Self-healable, stimuli-responsive bio-ionic liquid and sodium alginate conjugated hydrogel with tunable Injectability and mechanical properties for the treatment of breast cancer.

Designing stimuli-responsive drug delivery vehicles with higher drug loading capacity, sustained and targeted release of anti-cancer drugs and able to mitigate the shortcomings of traditional systems is need of hour. Herein, we designed stimuli-responsive, self-healable, and adhesive hydrogel through synergetic interaction between [Cho][Gly] (Choline-Glycine) and sodium alginate (SA). The hydrogel was formed as a result of non-covalent interaction between the components of the mixture forming the fibre kind morphology; confirmed through FTIR/computational analysis and SEM/AFM images. The hydrogel exhibited excellent mechanical strength, self-healing ability, adhesive character and most importantly; adjustable injectability. In vitro biocompatibility of the hydrogel was tested on HaCaT and MCF-7 cells, showing >92 % cell viability after 48 h. The hemolysis ratio (<4 %) of the hydrogel confirmed the blood compatibility of the hydrogel. When tested for drug-loading capacity, the hydrogel show 1500 times drug loading for the 5-fluorouracil (5-FU) against the SA based hydrogel. In vitro release data indicated that 5-FU have more preference towards the cancerous cell condition, i.e. acidic pH (>85 %), whereas the drug-loaded hydrogel successfully killed the MCF-7 and HeLa cell with a

Production of 5-fluorouracil-loaded PLGA nanoparticles with toroidal microfluidic system and optimization of process variables by design of experiments.

In recent decades, microfluidics has presented new opportunities for the production of nanoparticles (NPs). However, to achieve rapid clinical translation, the production of PLGA NPs in a single microfluidic channel for both the pharmaceutical research and industry without the need for scaling is still limited. The aim of this study was to accomplish the production of reproducible and stable 5-FU loaded Poly(lactic-co-glycolic acid) (PLGA) NPs, using an innovative toroidal microfluidic system, for cancer therapy. The toroidal microfluidic system enabled the production of spherical NPs ranging from 100 to 150 nm by adjusting both the TFR within the range of 5-15 mL/min and FRR between 1:3 and 1:7. A systematic assessment of critical process variables (total flow rate; TFR, flow rate ratio; FRR) for the production of PLGA NPs was conducted using Design of Experiment (DoE). The NPs, which exhibit a uniform size distribution, remained stable even after centrifugation and storage for 3 months at 4 °C. The encapsulation efficiency of drug and the concentration of NPs were not affected by changing process parameters. The effective 5-FU encapsulation into NPs resulted in a controlled in vitro drug release. Due to the controlled release profile of the 5-FU loaded PLGA NPs, the formulation was a promising candidate for mitigating the toxic side effects of free 5-FU and improving cancer treatment. In conclusion, toroidal microfluidic system enables high-volume production of stable PLGA NPs, both with and without 5-FU.

Delivery of 5-fluorouracil for cancer therapy using aptamer-based nonlinear hybridization chain reaction.

5-Fluorouracil (5-FU) is a conventional nucleotide analogue used for cancer treatment. However, its clinical application faces challenges such as low stability and non-specific toxicity. With the remarkable advancements in DNA nanotechnology, DNA-based self-assembled nanocarriers have emerged as powerful tools for delivering nucleotide drugs. In this study, we have designed a non-linear hybrid chain reaction involving a fuel strand with AS1411 aptamer sequence to construct a dendritic structure capable of carrying 5-FU. This structure specifically targets cancer cells with overexpressed nucleolin on their surface, allowing the 5-FU to exert its anticancer effects and achieve therapeutic outcomes. Furthermore, we have also investigated the mechanistic action of this drug delivery system, aiming to establish a novel therapeutic platform for 5-FU treatment.

An acid-activatable fluorouracil prodrug for colorectal cancer synergistic therapy.

5-Fluorouracil has demonstrated certain efficiency in patients with colorectal cancer. However, significant side effects of use by injection are common. To address this issue defects, a reengineered 5'-deoxy-5-fluorocytidine (DFCR) based drug delivery system (POACa) is developed as a prominent tumor-selective nano-activator. Investigations demonstrate that the constructed nano-activator exhibits good biocompatibility and high therapeutic efficiency in mice with subcutaneous and orthotopic SW-480 colorectal tumors, as its activity is strictly dependent on the tumor-associated acid environment and thymidine phosphorylase. These strategies diminish the off-target toxicity and improve the specificity and sensitivity of human colorectal cancer cells to 5-Fu, obtaining potent efficiency by the combination of H2O2 mediated oxidative stress, calcium overload and 5-Fu-induced chemotherapy (the combination index is 0.11). Overall, the engineered nano-activator exhibits a high therapeutic index in vitro and in vivo. STATEMENT OF SIGNIFICANCE: In this study, we designed and prepared a pH-responsive polymer to synchronously deliver DFCR (5'-deoxy-5-fluorocytidine, a prodrug of 5-Fu), Ca2+ and H2O2. The constructed nano-activator was denoted as POACa. (1) To address the problem of premature leakage of cargo by physical embedding, our research modified the inactive prodrug DFCR through chemical bonding. (2) The activation of the prepared nano-activator was strictly dependent on the tumor-associated acid environment and thymidine phosphorylase, providing the drug delivery system with inherent safety. (3) A distinctly low combination index value (0.11) of CaO2 and DFCR indicated that POACa has a prominent tumor suppression effect by tumor calcium overload sensitized chemotherapy and H2O2 mediated cytotoxicity.

PEG-modified Fe2O3 coated agarose hydrogel: A synthesized nanocomposite for regulated 5-fluorouracil delivery.

An innovative pH-responsive nanocomposite, comprising agarose (AGA) modified with polyethylene glycol (PEG) hydrogel and coated with ferric oxide (Fe2O3), has been formulated to facilitate the precise administration of 5-fluorouracil (5-Fu) to breast cancer cells. By utilizing a double emulsion technique, the size of the nanocomposites was significantly reduced through the application of almond oil; the inclusion of span 80 further improved their uniformity. The physiochemical properties of the nanocomposite were thoroughly examined by Fourier Transformed Infrared (FT-IR), X-ray diffraction (XRD), Field Emission-Scanning Electron Microscope (FE-SEM), Vibrating Sample Magnetometer (VSM), dynamic light scattering (DLS), and zeta potential tests. The verification of the uniform particle distribution was achieved by employing FE-SEM and VSM analyses. The average diameter of the particles was 223 nm, and their zeta potential was -47.6 mV. In addition, the nanocomposite exhibited a regulated release of 5-Fu at pH 5.4 and pH 7.4, as indicated by an in vitro drug release profile. PEG-AGA- Fe2O3@5-Fu exhibited biocompatibility, as indicated by the lack of deleterious effects observed in tumor cells. This revolutionary nanocomposite demonstrates exceptional promise for breast cancer treatment, underscoring its significance as a major advancement in the pursuit of novel nanotechnologies for cancer therapy.

Fluoro-Crown Ether Phosphate as Efficient Cell-Permeable Drug Carrier by Disrupting Hydration Layer.

Fast and direct permeation of drug molecules is crucial for effective biotherapeutics. Inspired by a recent finding that fluorous compounds disrupt the hydrogen-bonded network of water, we developed fluoro-crown ether phosphate CyclicFP-X. This compound acts as a fast cell-permeating agent, enabling direct delivery of various bioactive cargos (X) into cancer cells without endocytic entrapment. In contrast, its nonfluorinated cyclic analog (CyclicP-X) failed to achieve cellular internalization. Although the acyclic fluorous analog AcyclicFP-X was internalized, this process occurred slowly owing to the involvement of an endocytic trapping pathway. Designed with a high fluorine density, CyclicFP-X exhibits compactness, polarity, and high-water solubility, facilitating lipid vesicle fusion by disrupting their hydration layers. Raman spectroscopy confirmed the generation of dangling -OH bonds upon addition of CyclicFP-OH to water. Furthermore, conjugating CyclicFP-X with fluorouracil (FU, an anticancer drug) via a reductively cleavable disulfide linker (CyclicFP-SS-FU) demonstrated the general utility of fluoro-crown ether phosphate as a potent carrier for biotherapeutics.

Nanofibers Embedded with Nanoparticles as Carriers for the Controlled Release of Anticancer Drug: Promoting the Apoptosis of Breast Cancer Cell Line and Growth Inhibition of Microbial Strains.

The polymeric nanofiber mats were produced from polylactic acid, methylcellulose, and polyethylene glycol with 5-fluorouracil (5Fu) drug and iron oxide (Fe3O4) nanoparticles. Spectral and crystallographic studies clearly elucidated the ionic interactions, structure and nature of the mats. Fe3O4 nanoparticles <10 nm in size, along with methyl cellulose and polyethylene glycol, have significantly reduced the size of nanofiber mats. The mechanical properties for the mats was found to be challenging; however, surface wettability, swelling capacity, and drug encapsulation efficiency results were promising. A controlled drug release pattern was observed from in vitro drug release study, zero-order kinetics, and a Higuchi model. Nanofiber mats showed higher anticancer activity (78%) against MDA-MB 231 cancer cells, which reveals that a small amount of 5Fu drug (15.86%) with high levels of O2••, H2O2, and OH• radicals generated from Fe3O4 have catalyzed the Fenton's reaction to eradicate the cancer cells, in a shorter span of 24 h, itself. In addition, the apoptosis assay by dual AO/PI staining method clearly exhibited the apoptotic cancer cells by fluorescence microscopy. Incorporation of Fe3O4 nanoparticles enhanced the anticancer activity of the mats, compared to the commercially available standard 5Fu drug. Nanofiber mats significantly controlled the growth of selected pathogenic microbial strains by the action of the 5Fu drug and Fe3+ ions. The degradation of mats was investigated by an in vitro mass loss study for a period of 360 days. In a nutshell, promising nanofiber mats were produced as targeted drug delivery devices for chemotherapy.

Echogenic Gold Nanorod Incorporated Hybrid Poly(2-oxazoline) Nanocapsules for Real-Time Ultrasound/Fluorescent Imaging and Targeted Cancer Theranostics.

In recent years, various nanocarrier systems have been explored to enhance the targeting of cancer cells by improving the ligand-receptor interactions between the nanocarrier and cancer cells for selective cancer cell imaging and targeted delivery of anticancer drugs. Herein, we report multifunctional hydrogen-bonded multilayer nanocapsules functionalized with both folic acid-derived quantum dots (FAQDs) and gold nanorods (AuNRs) for targeted cancer therapy and cancer cell imaging using fluorescence microscopy and medical-range ultrasound imaging systems. The encapsulation efficiency of nanocapsules was found to be 49% for 5-fluorouracil (5-FU). The release percentage reached a plateau at 37% after 1 h at pH 7.4 and increased to 57% after 3 h when the release pH was decreased to pH 5.5 (i.e., the pH of the tumor environment). Under ultrasound irradiation, the release was significantly accelerated, with a total release of 52% and 68% after only 6 min at pH 7.4 and pH 5.5, respectively. While the sonoporation process plays an important role in anticancer activity experiments under ultrasound exposure by generating temporary pores, the targeting ability of FAQDs brings the capsules closer to the cell membrane and improves the cellular uptake of the released drug, thereby increasing local drug concentration. In vitro cytotoxicity experiments with HCT-116 and HEp-2 cells demonstrated anticancer activities of 96% and 98%, respectively. The nanocapsules showed enhanced ultrasound scattering signal intensity and bright spots under ultrasound exposure, most likely caused by high scattering ability and internal reflections of preloaded AuNRs in the interior structure of the nanocapsules. Hence, the demonstrated nanocapsule system not only has the potential to be used as an integrated system for early- stage detection and treatment of cancer cells but also has the ability for live tracking and imaging of cancer cells while undergoing treatment with chemotherapy and radiation therapy.

Different Drug Mobilities in Hydrophobic Cavities of Host-Guest Complexes between ß-Cyclodextrin and 5-Fluorouracil at Different Stoichiometries: A Molecular Dynamics Study in Water.

Cyclodextrins (CDs) are cyclic oligosaccharides able to form noncovalent water-soluble complexes useful in many different applications for the solubilization, delivery, and greater bioavailability of hydrophobic drugs. The complexation of 5-fluorouracil (5-FU) with natural or synthetic cyclodextrins permits the solubilization of this poorly soluble anticancer drug. In this theoretical work, the complexes between ß-CD and 5-FU are investigated using molecular mechanics (MM) and molecular dynamics (MD) simulations in water. The inclusion complexes are formed thanks to the favorable intermolecular interactions between ß-CD and 5-FU. Both 1:1 and 1:2 ß-CD/5-FU stoichiometries are investigated, providing insight into their interaction geometries and stability over time in water. In the 1:2 ß-CD/5-FU complexes, the intermolecular interactions affect the drug's mobility, suggesting a two-step release mechanism: a fast release for the more exposed and hydrated drug molecule, with greater freedom of movement near the ß-CD rims, and a slow one for the less-hydrated and well-encapsulated and confined drug. MD simulations study the intermolecular interactions between drugs and specific carriers at the atomistic level, suggesting a possible release mechanism and highlighting the role of the impact of the drug concentration on the kinetics process in water. A comparison with experimental data in the literature provides further insights.

Hyaluronic acid-conjugated methotrexate and 5-fluorouracil for targeted drug delivery.

The delivery of chemotherapeutical drugs via nanomaterials has become a focus of pharmaceutical research over several decades due to improved drug delivery to cancer cells, decreased side effects on normal tissues, and increased therapeutic efficacy. Herein, a novel hyaluronic acid-conjugated methotrexate and 5-fluorouracil nanodrug system has been developed to address the critical limitations associated with the high toxicity and side effects of methotrexate and 5-fluorouracil. Furthermore, this nanodrug system enhances the targeting capacity of drug molecules and facilitates the potential integration of multimodal drug therapies. Concomitantly, the synergistic effects of MTX with 5-fluorouracil have been shown to improve the therapeutic index of MTX while attenuating the associated toxicities of MTX. The structure and micromorphology of the novel nanodrug can be confirmed by 1HNMR, FT-IR, UV-Vis, DLS, TEM, and AFM. Due to the ability of HA to bind to CD44 receptors activated on the surface of cancer cells and its enhanced permeability and retention (EPR) effect, the novel nanodrug we designed and synthesized can effectively target cancer cells. Cell counting Kit-8 (CCK8), flow cytometry, and live-dead staining assays in vitro showed that this nanodrug system had high targeting and antitumor activity against CD44 receptors. By using drugs to act on patient-derived colorectal, liver, and breast cancer organoids, the anticancer effect of the nanodrug was identified and verified. These results showed that the nanodrug system developed in this study may have great potential as a targeted therapy for cancer.

Preparation of novel sulfated polysaccharide-carboxymethyl-5-fluorouracil-folic acid conjugates for targeted anticancer drug delivery.

GFP1, a sulfated polysaccharide extracted from Grateloupia filicina, exhibits remarkable immunomodulatory activity. To reduce the side effects of 5-fluorouracil (5-FU), GFP1 was employed as a macromolecular carrier to synthesize of GFP1-C-5-FU by reacting with carboxymethyl-5-fluorouracil (C-5-FU). Subsequently, this new compound was reacted with folic acid (FA) through an ester bond, forming novel conjugates named GFP1-C-5-FU-FA. Nuclear magnetic resonance analysis confirmed the formation of GFP1-C-5-FU-FA. In vitro drug release studies revealed that the cumulative release rate of C-5-FU reached 46.9 % in phosphate buffer (pH 7.4) after 96 h, a rate significantly higher than that of the control groups, indicating the controlled drug release behavior of GFP1-C-5-FU-FA. Additionally, in vitro anticancer assays demonstrated the potent anticancer activity of GFP1-C-5-FU-FA conjugates, as evidenced by the reduced viability of HeLa and AGS cancer cells, along with increased levels of apoptosis and cellular uptake. Western blot analysis indicated that the GFP1-C-5-FU-FA conjugate effectively enhanced phosphorylation in cancer cells through the NF-kB and MAPK pathways, thereby promoting apoptosis. These findings highlight the potential of folate-targeted conjugates in efficiently treating HeLa and AGS cancer cells in vitro and lay a robust theoretical groundwork for future in vivo anti-cancer research involving these cells.

Dextran-based nanoparticles with 5-FU-conjugated polymethacrylate segments for drug delivery: Synthesis of amphiphilic graft copolymers by mechanochemical solid-state polymerization and characterization.

Dextran (Dx) is a biodegradable and biocompatible polysaccharide, thus promising as a drug delivery carrier for tumor therapy. Herein, we applied mechanical energy to a high molecular weight Dx to control its molecular weight and simultaneously generate mechanoradicals. The solid-state polymerization of methacrylate- or methacrylamide derivatives initiated with Dx mechanoradicals showed polymer conversion of >95%, yielding Dx-based graft copolymers with molecular weights of approximately 30,000 g mol-1. The Dx-based graft copolymers with hydrophobic segments formed nanoparticles with a particle size of 25-35 nm in an aqueous solution. The anti-pancreatic tumor drug 5-fluorouracil (5-FU) was covalently conjugated onto the hydrophobic segments of the amphiphilic Dx, and the nanoparticles were also prepared. The drug release profile from 5-FU-conjugated nanoparticles corresponded well to the Korsmeyer-Peppas model applied to drug release from matrix substrates, and was also immensely predicted by the Logistic and Gompertz curves. The 5-FU-conjugated nanoparticles showed cytotoxicity against the pancreatic adenocarcinoma cell lines (BxPC-3) that were not significantly inferior to the 5-FU positive group. Furthermore, the fluorescein-labeled nanoparticles internalized into BxPC-3 within 6 h and actively migrated into the cytosol. These results suggest that Dx-based graft copolymers with hydrophobic segments might be used to enhance therapeutic activity.