Magnetic particle anchored reduction and pH responsive nanogel for enhanced intracellular drug delivery

Mussel-inspired surface-engineering of 3D printed scaffolds employing bedecked transition metal for accelerated bone tissue regeneration

In modern civilization with fast work culture and uncontrolled lifestyles increase bone-related problems, moreover, lack of auto-regeneration of bone, indulge to formulate a suitable methodology to get rid of this problem. In this article, nanohydroxyapatite (nHA) decorated hierarchical titanium phosphate (TP) was synthesized by solvothermal process and incorporated into newly synthesized tartaric acid-based polyurethane (PU) through in situ technique. The porous 3D scaffold was fabricated by most advanced 3D printing technique with desired porous structure in a controlled manner. The biochemical properties of scaffold's surface were improved via immobilizing polydopamine (PDA) at ambient temperature. Elemental analysis indicated that TP-doped nanohybrid scaffolds experienced higher amount of PDA immobilization as compared to pristine and nHA-doped scaffolds. The unoccupied 'd' orbital of introduced Ti can form a coordinate bond with catechol groups of dopamine (DA) which augments PDA deposition on the scaffold's surface. Furthermore, the higher effective nuclear charge (Z⁎) of tetravalent Ti ion generates an effective dative bond with the urethane groups of PU chain which improves hardness and tensile strength (TS) of produced nanocomposites (PU/TP-nHA) remarkably by 71.3 % and 126 % compared to pristine PU. Ti-doped nanohybrid scaffolds, containing calcium and phosphate components with higher amounts of deposited PDA exhibited improved in vitro osteogenic bioactivity. Moreover, in vivo study expressed superior bone regeneration efficacy of the TP-doped nHA-integrated PU scaffold without showing any organ toxicity. Thus, the optimum level of TP-doped nHA with higher amount of PDA-immobilized PU nanohybrid scaffold would be a suitable bone graft substitute in bone regeneration applications.

Intelligent responsive nanogels: New Horizons in cancer therapy

Biologically engineered nanogels formed through sophisticated intramolecular crosslinking processes represent the forefront of next-generation drug delivery systems. These innovative systems offer many advantages, like adjustable size, satisfactory biocompatibility, and minimal toxicity. Their unique attributes facilitate deep penetration and long-term retention of drugs in tumors, effectively enhancing the anti-tumor effects. Nonetheless, the rapid disintegration of nanogels and the subsequent triggering of drug release at the tumor site pose significant challenges in achieving more effective and precise tumor treatments. Therefore, increasing research has been dedicated to exploring stimulus-responsive nanogels for enhancing tumor therapy. This review aims to encapsulate the research advancements in emerging stimulus-responsive antitumor nanogels. Firstly, a detailed exposition is provided on various endogenous stimulus-responsive nanogels, encompassing factors such as pH, hypoxia, enzymes, reactive oxygen species (ROS), and glutathione (GSH). Secondly, various nanogels triggered by exogenous stimuli such as light, ultrasound, temperature, and magnetic fields are elaborately presented. Furthermore, nanogels with multifaceted stimulus-responsive properties are also skillfully designed. Finally, the future directions, application prospects, and challenges of intelligent responsive nanogels in cancer treatment are highlighted.

Current Non-Metal Nanoparticle-Based Therapeutic Approaches for Glioblastoma Treatment

The increase in the variety of nano-based tools offers new possibilities to approach the therapy of poorly treatable tumors, which includes glioblastoma multiforme (GBM; a primary brain tumor). The available nanocomplexes exhibit great potential as vehicles for the targeted delivery of anti-GBM compounds, including chemotherapeutics, nucleic acids, and inhibitors. The main advantages of nanoparticles (NPs) include improved drug stability, increased penetration of the blood-brain barrier, and better precision of tumor targeting. Importantly, alongside their drug-delivery ability, NPs may also present theranostic properties, including applications for targeted imaging or photothermal therapy of malignant brain cells. The available NPs can be classified into two categories according to their core, which can be metal or non-metal based. Among non-metal NPs, the most studied in regard to GBM treatment are exosomes, liposomes, cubosomes, polymeric NPs, micelles, dendrimers, nanogels, carbon nanotubes, and silica- and selenium-based NPs. They are characterized by satisfactory stability and biocompatibility, limited toxicity, and high accumulation in the targeted tumor tissue. Moreover, they can be easily functionalized for the improved delivery of their cargo to GBM cells. Therefore, the non-metal NPs discussed here, offer a promising approach to improving the treatment outcomes of aggressive GBM tumors.

Synthesis and Characterization of a pH- and Temperature-Sensitive Fe3O4-SiO2-Poly(NVCL-co-MAA) Nanocomposite for Controlled Delivery of Doxorubicin Anticancer Drug

This work reports the synthesis, characterization, and in vitro release studies of pH- and temperature-sensitive Fe₃O₄-SiO₂-poly(NVCL-co-MAA) nanocomposite. Fe₃O₄ nanoparticles were prepared by chemical coprecipitation, coated with SiO₂ by the Stöber method, and functionalized with vinyl groups. The copolymer poly(N-vinylcaprolactam-co-methacrylic acid) (poly(NVCL-co-MAA)) was grafted onto the functionalized Fe₃O₄-SiO₂ nanoparticles by free radical polymerization. XRD, FTIR, TGA, VSM, and TEM techniques were performed to characterize the nanocomposite. The release behavior of Doxorubicin (DOX) loaded in the nanocomposite at pH 5.8 and 7.4, and two temperatures, 25 and 37 °C, was studied. According to the release studies, approximately 55% of DOX is released in 72 h at pH 7.4, regardless of temperature. At pH 5.8, 78% of DOX was released in 48 h at 25 °C, and when increasing the temperature to 37 °C, more than 95 % of DOX was released in 24 h. The DOX release data treated with Zero-order, first-order, Higuchi, and Korsmeyer-Peppas models showed that Higuchi's model best fits the data, indicating that the DOX is released by diffusion. The findings suggest that the synthesized nanocomposite may be useful as a DOX carrier in biomedical applications.

Synthesis of Magneto-Controllable Polymer Nanocarrier Based on Poly(N-isopropylacrylamide-co-acrylic Acid) for Doxorubicin Immobilization

In this work, the preparation procedure and properties of anionic magnetic microgels loaded with antitumor drug doxorubicin are described. The functional microgels were produced via the in situ formation of iron nanoparticles in an aqueous dispersion of polymer microgels based on poly(N-isopropylacrylamide-co-acrylic acid) (PNIPAM-PAA). The composition and morphology of the resulting composite microgels were studied by means of X-ray diffraction, Mössbauer spectroscopy, IR spectroscopy, scanning electron microscopy, atomic-force microscopy, laser microelectrophoresis, and static and dynamic light scattering. The forming nanoparticles were found to be β-FeO(OH). In physiological pH and ionic strength, the obtained composite microgels were shown to possess high colloid stability. The average size of the composites was 200 nm, while the zeta-potential was -27.5 mV. An optical tweezers study has demonstrated the possibility of manipulation with microgel using external magnetic fields. Loading of the composite microgel with doxorubicin did not lead to any change in particle size and colloidal stability. Magnetic-driven interaction of the drug-loaded microgel with model cell membranes was demonstrated by fluorescence microscopy. The described magnetic microgels demonstrate the potential for the controlled delivery of biologically active substances.

Redox-Responsive Drug Delivery Systems: A Chemical Perspective

With the widespread global impact of cancer on humans and the extensive side effects associated with current cancer treatments, a novel, effective, and safe treatment is needed. Redox-responsive drug delivery systems (DDSs) have emerged as a potential cancer treatment with minimal side effects and enhanced site-specific targeted delivery. This paper explores the physiological and biochemical nature of tumors that allow for redox-responsive drug delivery systems and reviews recent advances in the chemical composition and design of such systems. The five main redox-responsive chemical entities that are the focus of this paper are disulfide bonds, diselenide bonds, succinimide-thioether linkages, tetrasulfide bonds, and platin conjugates. Moreover, as disulfide bonds are the most commonly used entities, the review explored disulfide-containing liposomes, polymeric micelles, and nanogels. While various systems have been devised, further research is needed to advance redox-responsive drug delivery systems for cancer treatment clinical applications.

Tea Polyphenol Liposomes Overcome Gastric Mucus to Treat Helicobacter Pylori Infection and Enhance the Intestinal Microenvironment

Infection with Helicobacter pylori (Hp) is one of the leading causes of stomach cancer. The ability to treat Hp infection is hampered by a lack of stomach gastric acid environment. This work introduces a nanoliposome that can rapidly adjust the gastric acid environment to ensure a drug's optimal efficacy. We introduce CaCO₃@Fe-TP@EggPC nanoliposomes (CTE NLs) that are composed of Fe³⁺ and tea polyphenols (TPs) forming complexes on the surface of internal CaCO₃ and then with lecithin producing a phospholipid bilayer on the polyphenols' outer surface. Through the action of iron-TP chelate, the phospholipid layer can fuse with the bacterial membrane to eliminate Hp. Furthermore, CaCO₃ can promptly consume the excessive gastric acid, ensuring an ideal operating environment for the chelate. TPs, on the other hand, can improve the inflammation and gut microbes in the body. The experimental results show that CTE NLs can quickly consume protons in the stomach and reduce the bacterial burden by 1.2 orders of magnitude while reducing the inflammatory factors in the body. The biosafety evaluation revealed that nanoliposomes have good biocompatibility and provide a new strategy for treating Hp infection.

Progress in drug-delivery systems in cardiovascular applications: stents, balloons and nanoencapsulation

Drug-delivery systems in cardiovascular applications regularly include the use of drug-eluting stents and drug-coated balloons to ensure sufficient drug transfer and efficacy in the treatment of cardiovascular diseases. In addition to the delivery of antiproliferative drugs, the use of growth factors, genetic materials, hormones and signaling molecules has led to the development of different nanoencapsulation techniques for targeted drug delivery. The review will cover drug delivery and coating mechanisms in current drug-eluting stents and drug-coated balloons, novel innovations in drug-eluting stent technologies and drug encapsulation in nanocarriers for delivery in vascular diseases. Newer technologies and advances in nanoencapsulation techniques, such as the use of liposomes, nanogels and layer-by-layer coating to deliver therapeutics in the cardiovascular space, will be highlighted.

Dually Cross-Linked Core-Shell Structure Nanohydrogel with Redox-Responsive Degradability for Intracellular Delivery

A redox-responsive nanocarrier is a promising strategy for the intracellular drug release because it protects the payload, prevents its undesirable leakage during extracellular transport, and favors site-specific drug delivery. In this study, we developed a novel redox responsive core-shell structure nanohydrogel prepared by a water in oil nanoemulsion method using two biocompatible synthetic polymers: vinyl sulfonated poly(N-(2-hydroxypropyl) methacrylamide mono/dilactate)-polyethylene glycol-poly(N-(2-hydroxypropyl) methacrylamide mono/dilactate) triblock copolymer, and thiolated hyaluronic acid. The influence on the nanohydrogel particle size and distribution of formulation parameters was investigated by a three-level full factorial design to optimize the preparation conditions. The surface and core-shell morphology of the nanohydrogel were observed by scanning electron microscope, transmission electron microscopy, and further confirmed by Fourier transform infrared spectroscopy and Raman spectroscopy from the standpoint of chemical composition. The redox-responsive biodegradability of the nanohydrogel in reducing environments was determined using glutathione as reducing agent. A nanohydrogel with particle size around 250 nm and polydispersity index around 0.1 is characterized by a thermosensitive shell which jellifies at body temperature and crosslinks at the interface of a redox-responsive hyaluronic acid core via the Michael addition reaction. The nanohydrogel showed good encapsulation efficiency for model macromolecules of different molecular weight (93% for cytochrome C, 47% for horseradish peroxidase, and 90% for bovine serum albumin), capacity to retain the peroxidase-like enzymatic activity (around 90%) of cytochrome C and horseradish peroxidase, and specific redox-responsive release behavior. Additionally, the nanohydrogel exhibited excellent cytocompatibility and internalization efficiency into macrophages. Therefore, the developed core-shell structure nanohydrogel can be considered a promising tool for the potential intracellular delivery of different pharmaceutical applications, including for cancer therapy.

Strategic Design of Intelligent-Responsive Nanogel Carriers for Cancer Therapy

Owing to the distinctive constituents of tumor tissue from those healthy organs, nanomedicine strategies show significant potentials in smart drug delivery. Nowadays, stimuli-responsive nanogels are playing increasingly important roles in the application of cancer therapy because of their sensitivity to various internal or external physicochemical stimuli, which exhibit site-specific and markedly enhanced drug release. Besides, nanogels are promising as drug carriers because of their porous structures, good biocompatibility, large surface area, and excellent capability with drugs. Taking advantage of multiresponsiveness, recent years have witnessed the rapid evolution of stimulus-responsive nanogels from monoresponsive to multiresponsive systems; however, there lacks a comprehensive review summarizing these reports. In this Review, we discuss the properties, synthesis, and characterization of nanogels. Moreover, tumor microenvironment and corresponding designing strategies for stimuli-response nanogels, both exogenous (temperature, magnetic field, light) and endogenous (pH, biomolecular, redox, ROS, pressure, hypoxia) are summarized on the basis of the recent advances in multistimuli-responsive nanogel systems. Nanogel and two-dimensional material composites show excellent performance in the field of constructing multistimulus-responsive nanoparticles and precise intelligent drug release integrated system for multimodal cancer diagnosis and therapy. Finally, potential progresses and suggestions are provided for the further design of hybrid nanogels based on emerging two-dimensional materials.

MTX-Loaded Dual Thermoresponsive and pH-Responsive Magnetic Hydrogel Nanocomposite Particles for Combined Controlled Drug Delivery and Hyperthermia Therapy of Cancer

In recent years, the exploitation of magnetic nanoparticles in smart polymeric matrices have received increased attention in several fields as site-specific drug delivery systems. Here, ultrasonic-assisted emulsion copolymerization of N-isopropylacrylamide (NIPAM) and 2-(N,N-diethylaminoethyl) methacrylate (DEAEMA) in the presence of Fe₃O₄ nanoparticles was employed to prepare pH- and temperature-responsive magnetite nanocomposite particles (MNCPs). The obtained MNCPs were fully characterized by TEM, DSC, FT-IR, VSM, and XRD techniques. They had an average particle size of 70 nm with a lower critical solution temperature of 42 °C and superparamagnetic properties. In addition, MNCPs were loaded with methotrexate (MTX) as an anticancer drug, and their in vitro drug release was studied in different pH values and temperatures and in the presence of an alternating magnetic field. Noteworthy that the highest rate of MTX release was observed at pH 5.5 and 42 °C. Cell viability of the treated MCF-7 human breast cancer cell line with free MTX, MNCPs, and MTX-loaded MNCPs or in combination with magnetic hyperthermia (MHT) and water-based hyperthermia was comparatively studied. The obtained results showed about 17% higher antiproliferative activity for the MTX-loaded MNCPs accompanied by MHT relative to that of free MTX.