Synthesis of thermosensitive magnetic nanocarrier for controlled sorafenib delivery

Conjugation of hydrazine to PEGylated silica-coated magnetite nanoparticles as pH-responsive magnetic nanocarriers for covalent loading and controlled release of doxorubicin

Breast cancer is a major health issue among women, and doxorubicin (DOX) is a commonly used treatment. However, its clinical application is limited by its considerable toxicity. This study introduces an acidity-responsive magnetite nanoparticle-based nanocarrier for effective breast cancer treatment. The magnetite nanoparticles were initially coated with [3-(2,3-epoxypropoxy)-propyl]-trimethoxysilane, an epoxysilane cross-linker, to enhance their stability and functional properties. Subsequently, NH2-PEG-COOH was conjugated to epoxy-functionalized silica-coated magnetite nanoparticles to improve biocompatibility and introduce reactive carboxyl groups. These carboxyl groups were further modified with hydrazine via carbodiimide-mediated amidation to construct magnetic nanocarriers (MNC). DOX was loaded into the system via acid-sensitive hydrazone bonds, resulting in the final MNC-DOX formulation. The DOX loading process followed the Ho-McKay model, demonstrating chemical adsorption kinetics with a high loading capacity of 433.147 mg/g. The acid-sensitive hydrazone bond facilitated rapid DOX release in response to the acidic tumor microenvironment, with release kinetics following the Korsmeyer-Peppas model, indicative of Fickian diffusion. In vitro cytotoxicity assays revealed that MNC-DOX exhibited significant cytotoxicity against MCF-7 breast cancer cells. This novel MNC-DOX formulation holds great potential for enhancing cancer therapy, highlighting its responsiveness to subtle pH changes and its ability to improve the targeted delivery and controlled release of chemotherapeutic agents.

Evaluation of a temperature-responsive magnetotocosome as a magnetic targeting drug delivery system for sorafenib tosylate anticancer drug

In this investigation, a polymeric fusion of chitosan (CS) and thermosensitive poly (N-isopropyl acrylamide) - PNIPAAm - encapsulated a magnetotocosome, biocompatible nanocarrier. This encapsulation strategy demonstrated improved drug entrapment efficiency, achieving up to 98.8 %. Additionally, it exhibited extended stability, optimal particle dimensions, and the potential for industrial scaling, thus facilitating controlled drug delivery of sorafenib tosylate to cancerous tissue. Reversible Addition-Fragmentation Chain Transfer (RAFT) techniques were employed to synthesize PNIPAAm. The effects of polymer molecular weight and polydispersity index on the lower critical solution temperature (LCST) were evaluated. The resulting polymeric amalgamation, involving the thermosensitive PNIPAAm synthesized using RAFT techniques and CS that coated the magnetotocosome (CS-Raft PNIPAAm-magnetotocosome) with an LCST approximately at 45 °C, holds the potential to enhance drug bioavailability and enable applications in hyperthermia treatment, controlled release, and targeted drug delivery.

Sorafenib-Based Drug Delivery Systems: Applications and Perspectives

As a Food and Drug Administration (FDA)-approved molecular-targeted chemotherapeutic drug, sorafenib (SF) can inhibit angiogenesis and tumor cell proliferation, leading to improved patient overall survival of hepatocellular carcinoma (HCC). In addition, SF is an oral multikinase inhibitor as a single-agent therapy in renal cell carcinoma. However, the poor aqueous solubility, low bioavailability, unfavorable pharmacokinetic properties and undesirable side effects (anorexia, gastrointestinal bleeding, and severe skin toxicity, etc.) seriously limit its clinical application. To overcome these drawbacks, the entrapment of SF into nanocarriers by nanoformulations is an effective strategy, which delivers SF in a target tumor with decreased adverse effects and improved treatment efficacy. In this review, significant advances and design strategies of SF nanodelivery systems from 2012 to 2023 are summarized. The review is organized by type of carriers including natural biomacromolecule (lipid, chitosan, cyclodextrin, etc.); synthetic polymer (poly(lactic-co-glycolic acid), polyethyleneimine, brush copolymer, etc.); mesoporous silica; gold nanoparticles; and others. Co-delivery of SF and other active agents (glypican-3, hyaluronic acid, apolipoprotein peptide, folate, and superparamagnetic iron oxide nanoparticles) for targeted SF nanosystems and synergistic drug combinations are also highlighted. All these studies showed promising results for targeted treatment of HCC and other cancers by SF-based nanomedicines. The outlook, challenges and future opportunities for the development of SF-based drug delivery are presented.

pH-responsive glycodendrimer as a new active targeting agent for doxorubicin delivery

The present study synthesized a new kind of pH-responsive active targeting glycodendrimer (ATGD) for doxorubicin delivery to cancerous cells. First, the glycodendrimer was synthesized based on the cultivation of chitosan dendrons on amine-functionalized, silica-grafted cellulose nanocrystals. Afterward, glycodendrimer was conjugated with folic acid to provide a folate receptor-targeting agent. The response surface method was employed to obtain the optimum conditions for the preparation of doxorubicin-loaded ATGD. The effect of doxorubicin/ATGD ratio, temperature, and pH on doxorubicin loading capacity was evaluated, and high loading capacity was achieved under optimized conditions. After determining doxorubicin release pattern at acidic and physiological pH, ATGD cytotoxicity was surveyed by MTT assay. Based on the results, the loading behavior of doxorubicin onto ATGD was in good agreement with monolayer-physisorption, and drug release was Fickian diffusion-controlled. ATGD could release the doxorubicin much more at acidic pH than physiological pH, corresponding to pH-responsive release behavior. Results of MTT assay confirmed the cytotoxicity of doxorubicin-loaded ATGD in cancer cells, while ATGD (without drug) was biocompatible with no tangible toxicity. These results suggested that ATGD has the potential for the treatment of cancer.

Investigation of temperature-responsive tocosomal nanocarriers as the efficient and robust drug delivery system for Sunitinib malate anti-cancer drug: Effects of MW and chain length of PNIPAAm on LCST and dissolution rate

In this study, for the first time, the coated tocosome by blend of chitosan, CS, and poly(N-isopropylacrylamide), PNIPAAm, was developed as the efficient and robust drug delivery system with improved drug encapsulation efficiency, extended stability, proper particle size and industrial upscaling for Sunitinib malate anti-cancer drug. Tocosome was synthesized by using Mozafari method as a scalable and robust method and without the need for organic solvents. The effects of tocosome composition and drug concentration on the stability, particle size of tocosome, zeta potential, encapsulation efficacy and loading of drug into it were investigated by Taguchi method, and optimum composition was selected for combining with the polymeric blend. Homopolymer of PNIPAAm was synthesized by two different polymerization methods, including free radical and reversible addition-fragmentation chain transfer (RAFT). Effects of molecular weight (MW) and chain length of the polymers on lower critical solution temperature (LCST) were examined. The developed nanocarrier in this research, CS-Raft-PNIPAAm-tocosome, indicated LCST value beyond 37°C (about 45°C) and this is suitable for hyperthermia and spatio-temporal release of drug particles.

Chitosan as a matrix of nanocomposites: A review on nanostructures, processes, properties, and applications

Chitosan is a biopolymer that is natural, biodegradable, and relatively low price. Chitosan has been attracting interest as a matrix of nanocomposites due to new properties for various applications. This study presents a comprehensive overview of common and recent advances using chitosan as a nanocomposite matrix. The focus is to present alternative processes to produce embedded or coated nanoparticles, and the shaping techniques that have been employed (3D printing, electrospinning), as well as the nanocomposites emerging applications in medicine, tissue engineering, wastewater treatment, corrosion inhibition, among others. There are several reviews about single chitosan material and derivatives for diverse applications. However, there is not a study that focuses on chitosan as a nanocomposite matrix, explaining the possibility of nanomaterial additions, the interaction of the attached species, and the applications possibility following the techniques to combine chitosan with nanostructures. Finally, future directions are presented for expanding the applications of chitosan nanocomposites.

Sorafenib for hepatocellular carcinoma: potential molecular targets and resistance mechanisms

Hepatocellular carcinoma (HCC) is the most widespread typical therapy-resistant, unresectable type of malignant solid tumour with a high death rate constituting huge medical concern. Sorafenib is a small molecule oral multi-target kinase potent inhibitor that acts by suppressing/blocking the multiplication of the tumour cells, angiogenesis, and encouraging apoptosis of the tumour cells. Though, the precise mechanism of tumour cell death induction by sorafenib is yet under exploration. Furthermore, genetic heterogeneity plays a critical role in developing sorafenib resistance, which leads the way to identify the need for predictive biomarkers responsible for drug resistance. Therefore, it is essential to find out the fundamental resistance mechanisms to expand therapeutic plans. The authors summarize the molecular concepts of resistance, progression, potential molecular targets, HCC management therapies, and discussion on the advancements expected in the coming future, inclusive of biomarker-driven treatment strategies, which may provide the prospects to design innovative therapeutically targeted strategies for the HCC treatment and the clinical implementation of emerging targeted agents.

pH-triggered intracellular release of doxorubicin by a poly(glycidyl methacrylate)-based double-shell magnetic nanocarrier

Two core-double-shell pH-sensitive nanocarriers were fabricated using Fe₃O₄ as magnetic core, poly(glycidyl methacrylate-PEG) and salep dialdehyde as the first and the second shell, and doxorubicin as the hydrophobic anticancer drug. Two nanocarriers were different in the drug loading steps. The interaction between the first and the second shell assumed to be pH-sensitive via acetal cross linkages. The structure of nanocarriers, organic shell loading, magnetic responsibility, morphology, size, dispersibility, and drug loading content were investigated by IR, NMR, TG, VSM, XRD, DLS, HRTEM and UV-Vis analyses. The long-term drug release profiles of both nanocarriers showed that the drug loading before cross-linking between the first and second shell led to a more pH-sensitive nanocarrier exhibiting higher control on DOX release. Cellular toxicity assay (MTT) showed that DOX-free nanocarrier is biocompatible having cell viability greater than 80% for HEK-293 and MCF-7 cell lines. Besides, high cytotoxic effect observed for drug-loaded nanocarrier on MCF-7 cancer cells. Cellular uptake analysis showed that the nanocarrier is able to transport DOX into the cytoplasm and perinuclear regions of MCF-7 cells. In vitro hemolysis and coagulation assays demonstrated high blood compatibility of nanocarrier. The results also suggested that low concentration of nanocarrier have a great potential as a contrast agent in magnetic resonance imaging (MRI).

Microfluidic fabrication and characterization of Sorafenib-loaded lipid-polymer hybrid nanoparticles for controlled drug delivery

Lipid polymer hybrid nanoparticles (LPHNPs) have been merged as potential nanocarriers for treatment of cancer. In the present study, LPHNPs loaded with Sorafenib (SFN) were prepared with PLGA, Lecithin and DSPE-PEG 2000 by using the bulk nanoprecipitation and microfluidic (MF) co-flow nanoprecipitation techniques. Herein, a glass capillary microfluidic device was primed to optimize the LPHNPs and compared to the bulk nanoprecipitation method. The morphological analysis of prepared LPHNPs revealed the well-defined spherical nano-sized particles in bulk nanoprecipitation method. Whereas, core shell morphology was observed in the MF method. The formulation prepared by the MF method (MF1-MF3) indicated relatively higher % EE (95.0%, 93.8% and 88.7%) and controlled release of the SFN from the particles as compared to the LPHNPs obtained by the bulk nanoprecipitation method. However, the release of SFN from all LPHNP formulation followed Higuchi model (R² = 0.9901-0.9389) with Fickian diffusion mechanism. Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC) and powder X-rays diffraction (pXRD) studies depicted the compatibility of SFN with all the structural components. In addition, the colloidal stability, in vitro cytotoxicity and cell growth inhibition studies of LPHNPs also demonstrated stability in biological media, biocompatibility and safety with enhanced anti-proliferative effects than the free SFN in breast cancer and prostate cancer cells. In conclusion, LPHNPs provided a prospective platform for the cancer chemotherapy and substantially improved the knowledge of fabrication and optimization of the hybrid nanoparticles.

Temperature-Responsive Magnetic Nanoparticles for Enabling Affinity Separation of Extracellular Vesicles

Small magnetic nanoparticles that have surfaces decorated with stimuli-responsive polymers can be reversibly aggregated via a stimulus, such as temperature, to enable efficient and rapid biomarker separation. To fully realize the potential of these particles, the synthesis needs to be highly reproducible and scalable to large quantity. We have developed a new synthesis for temperature-responsive magnetic nanoparticles via an in situ co-precipitation process of Fe2+/Fe3+ salts at room temperature with poly(acrylic acid)- block-poly( N-isopropylacrylamide) diblock co-polymer template, synthesized via the reversible addition-fragmentation chain-transfer polymerization method. These particles were 56% polymer by weight with a 6.5:1 Fe/COOH ratio and demonstrated remarkable stability over a 2 month period. The hydrodynamic diameter remained constant at ∼28 nm with a consistent transition temperature of 34 °C, and the magnetic particle separation efficiency at 40 °C was ≥95% over the 2 month span. These properties were maintained for all large-scale synthesis batches. To demonstrate the practical utility of the stimuli-responsive magnetic nanoparticles, the particles were incorporated into a temperature-responsive binary reagent system and efficiently separated a model protein biomarker (mouse IgG) as well as purified extracellular vesicles derived from a human biofluid, seminal plasma. The ease of using these particles will prove beneficial for various biomedical applications.

Smart pH responsive drug delivery system based on poly(HEMA-co-DMAEMA) nanohydrogel

The advent of smart nanohydrogel has revealed new opportunities for scientists to develop the most efficient anti-cancer vehicles with safe and biocompatible profile. In this experiment, using reversible addition-fragmentation chain transfer polymerization method as a novel, safe and smart pH responsive formulation of poly (hydroxyethyl methacrylate-co-N,N-dimethylaminoethyl methacrylate) and poly (ethylene glycol)-diacrylate as cross-linker were synthesized. The synthesized structure was confirmed by Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance methods. The pH responsive behavior of the synthesized particles was checked by size measurement in two different pH values (5.5 and 7.4) by dynamic light scattering and transmission electron microscopy. The prepared structure had nanometer sizes of 180 in medium with pH of 7.4, when it encountered acidic medium (e.g. pH 5.5), the particles swelled to about 400 nm. The efficiency of the prepared pH responsive nanohydrogels was tested as a drug delivery system. An anti-cancer drug, doxorubicin successfully interacted with this material. The release profiles of nanoparticles carrying drug molecules were checked in two different simulated pH of healthy organs (7.4) and tumor site (5.5). Despite lower release in pH of 7.4 (∼20%), an increased drug release of 80% was obtained in pH of 5.5. The in vitro toxicity assay, apoptosis evaluation and uptake experiments were performed on breast cancer cell line (MCF-7), which showed a time dependency cellular entrance, an enhanced cytotoxicity and apoptosis induction by the doxorubicin loaded nanoparticles. Hemolysis assays confirmed the safety and hemocompatibility of the developed nanohydrogel. The suitable size (<200 nm), pH responsive behavior, anti-proliferative activity and apoptosis induction in cancer cells and hemocompatibility were the noticeable features of the developed doxorubicin adsorbed nanoparticle, which introduced this formulation as an ideal vehicle in anti-cancer drug delivery.

Dual Drug Delivery of Sorafenib and Doxorubicin from PLGA and PEG-PLGA Polymeric Nanoparticles

Combinatorial drug delivery is a way of advanced cancer treatment that at present represents a challenge for researchers. Here, we report the efficient entrapment of two clinically used single-agent drugs, doxorubicin and sorafenib, against hepatocellular carcinoma. Biocompatible and biodegradable polymeric nanoparticles provide a promising approach for controlled drug release. In this study, doxorubicin and sorafenib with completely different chemical characteristics were simultaneously entrapped by the same polymeric carrier, namely poly(d,l-lactide-co-glycolide) (PLGA) and polyethylene glycol-poly(d,l-lactide-co-glycolide) (PEG-PLGA), respectively, using the double emulsion solvent evaporation method. The typical mean diameters of the nanopharmaceuticals were 142 and 177 nm, respectively. The PLGA and PEG-PLGA polymers encapsulated doxorubicin with efficiencies of 52% and 69%, respectively, while these values for sorafenib were 55% and 88%, respectively. Sustained drug delivery under biorelevant conditions was found for doxorubicin, while sorafenib was released quickly from the PLGA-doxorubicin-sorafenib and PEG-PLGA-doxorubicin-sorafenib nanotherapeutics.

Thin chitosan films containing super-paramagnetic nanoparticles with contrasting capability in magnetic resonance imaging

Magnetic nanoparticles have found application as MRI contrasting agents. Herein, chitosan thin films containing super-paramagnetic iron oxide nanoparticles (SPIONs) are evaluated in magnetic resonance imaging (MRI). To determine their contrasting capability, super-paramagnetic nanoparticles coated with citrate (SPIONs-cit) were synthesized. Then, chitosan thin films with different concentrations of SPIONs-cit were prepared and their MRI data (i.e., r ₂ and r ₂*) was evaluated in an aqueous medium. The synthesized SPIONs-cit and chitosan/SPIONs-cit films were characterized by FTIR, EDX, XRD as well as VSM with the morphology evaluated by SEM and AFM. The nanoparticle sizes and distribution confirmed well-defined nanoparticles and thin films formation along with high contrasting capability in MRI. Images revealed well-dispersed uniform nanoparticles, averaging 10 nm in size. SPIONs-cit's hydrodynamic size averaged 23 nm in diameter. The crystallinity obeyed a chitosan and SPIONs pattern. The in vitro cellular assay of thin films with a novel route was performed within Hek293 cell lines showing that thin films can be biocompatible.

Thermoresponsive Gels

Thermoresponsive gelling materials constructed from natural and synthetic polymers can be used to provide triggered action and therefore customised products such as drug delivery and regenerative medicine types as well as for other industries. Some materials give Arrhenius-type viscosity changes based on coil to globule transitions. Others produce more counterintuitive responses to temperature change because of agglomeration induced by enthalpic or entropic drivers. Extensive covalent crosslinking superimposes complexity of response and the upper and lower critical solution temperatures can translate to critical volume temperatures for these swellable but insoluble gels. Their structure and volume response confer advantages for actuation though they lack robustness. Dynamic covalent bonding has created an intermediate category where shape moulding and self-healing variants are useful for several platforms. Developing synthesis methodology-for example, Reversible Addition Fragmentation chain Transfer (RAFT) and Atomic Transfer Radical Polymerisation (ATRP)-provides an almost infinite range of materials that can be used for many of these gelling systems. For those that self-assemble into micelle systems that can gel, the upper and lower critical solution temperatures (UCST and LCST) are analogous to those for simpler dispersible polymers. However, the tuned hydrophobic-hydrophilic balance plus the introduction of additional pH-sensitivity and, for instance, thermochromic response, open the potential for coupled mechanisms to create complex drug targeting effects at the cellular level.

In vitro and in vivo assessment of EDTA-modified silica nano-spheres with supreme capacity of iron capture as a novel antidote agent

Mesoporous silica nanoparticles having structure of MCM-41 category with amine and EDTA functional groups in the pores were prepared using a co-condensation reaction. The synthetic steps eventuated in the mesoporous silica nanoparticles with spherical sizes lower than 50nm supposed to have high surface area. The nanoparticles' structure and functionality were characterized by FTIR spectroscopy and CHN analysis and the topography were examined by SEM and TEM and hydrodynamic sizes were demonstrated by DLS. The crystallinity and mesoporous pattern were figured out by XRD technique. Then the efficiency of these materials was tested in vitro and in vivo in adsorbing ferrous sulfate which is a supplement normally prescribed in treating iron deficiency and its overdose is potentially lethal, especially in young children. In vivo experiments illustrated that both nanoparticles could efficiently be administrated as an antidote agent against iron overdose, but EDTA-MSN nanoparticles were superior to NH₂-MSN nanoparticles.