A dual-targeting Fe3O4@C/ZnO-DOX-FA nanoplatform with pH-responsive drug release and synergetic chemo-photothermal antitumor in vitro and in vivo

Metal-organic frameworks as nanoplatforms for combination therapy in cancer treatment

The integration of nanotechnology into cancer treatment has revolutionized chemotherapy, boosted its effectiveness while reduced side effects. Among the various nanotherapeutic approaches, metal-organic frameworks (MOFs) stand out as promising carriers for targeted chemotherapy, with the added benefit of enabling combination therapies. MOFs, composed of metal ions or clusters linked by coordination bonds, tackle critical issues in traditional cancer treatments, such as poor stability, limited efficacy, and severe side effects. Their key advantages include customizable size and shape, diverse compositions, controlled porosity, large surface areas, ease of modification, and biocompatibility. This review highlights recent advancements in the use of MOFs for cancer therapy, showcasing their role in both monotherapies and combination strategies. Additionally, it explores the future potential and challenges of MOF-based platforms in tumor treatment.

3D printed gelatin/PTMC core/shell scaffolds with NIR laser-tuned drug/biomolecule release for cancer therapy and uterine regeneration

Surgical resection is an efficient treatment for cancerous tissues and uterine fibroids in the women uterus. However, the insufficiency of clinical interventions could result in tumor recurrence, and the defective tissues remained would cause intrauterine adhesions (IUAs) and further affect reproduction capacity. In this study, 3D printed hydrogel/poly(l-lactide-co-trimethylene carbonate) (PLLA-co-TMC, "PTMC" in short) core/shell scaffolds with NIR-tuned doxorubicin hydrochloride (DOX) and estradiol (E2) dual release were designed and fabricated for cancer therapy and uterine regeneration. Gelatin (Gel) and DOX were homogeneously mixed and then 3D printed to form Gel-DOX scaffolds. Gel-DOX scaffolds were then immersed in PTMC-PDA@E2 solution to fabricate Gel-DOX/PTMC-PDA@E2 core/shell scaffolds. Consequently, Gel-DOX/PTMC-PDA@E2 scaffolds could release DOX and E2 in a chronological manner, firstly delivering DOX assisted by phototherapy (PTT) to effectively kill Hela cells and then sustainably releasing E2 to promote uterine tissue regeneration. In vitro experiments showed that core/shell scaffolds exhibited excellent anticancer efficiency through the synergy of DOX release and hyperthermia ablation. Moreover, E2 could be sustainably released for over 28 days in vitro to promote the proliferation of bone marrow-derived mesenchymal stem cells (BMSCs). The novel Gel-DOX/PTMC-PDA@E2 core/shell scaffolds have therefore exhibited potential promise for the treatment of cancer therapy and uterine regeneration.

Magnetic targeting and pH-microwave dual responsive Janus mesoporous silica nanoparticles for drug encapsulation and delivery

In this paper, a new Janus-structured nano drug delivery carrier Fe3O4@TiO2&mSiO2was designed and synthesized, which consisted of a spherical head and a closely connected rod. The head was a nanocomposite of core/shell structure with magnetic spinel ferric tetraoxide core and anatase titanium dioxide shell (Fe3O4@TiO2), and the rod was ordered mesoporous silica (mSiO2). The nanocarriers showed excellent magnetic targeting capability (saturation magnetization, 25.18 emu g-1). The core/shell heads endowed the carriers with fine microwave responsiveness. The pore volume of mesoporous nanocarriers was 0.101 cm3g-1, and the specific surface area was 489.0 m2g-1. Anticancer drug doxorubicin could be loaded in the mesoporous of the carriers to form Fe3O4@TiO2&mSiO2-DOX. The drug loading capacity was 10.4%. Fe3O4@TiO2&mSiO2-DOX exhibited acid-sensitive and microwave-sensitive release properties along with good bio-compatibility. Fe3O4@TiO2&mSiO2Janus nanoparticles are expected to be ideal drug carriers.

Folate-mediated magnetic and pH/GSH dual-responsive metal-polymer-coordinated nanocomplexes for joint chemo/chemodynamic anti-breast cancer therapy

It is of great significance to develop a drug carrier that effectively targets chemotherapeutic drugs to the tumor site, improves therapeutic efficacy and reduces side effects associated with high-dose medicines. In the present study, an intelligent drug carrier system, FA-β-CD/DOX@Cu2+@GA@Fe3O4, was synthesized by skillfully introducing metal ions as a bridge base. The performance of the prepared FA-β-CD@Cu2+@GA@Fe3O4 metal-polymer-coordinated nanocomplexes were determined by UV-visible spectroscopy, NMR, FT-IR, XPS, VSM, DLS, and TEM analysis. The data showed that these nanocomplexes had good pH/GSH-responsive drug release behavior, and enabled enhanced magnetic and folic acid-mediated tumor cell targeting. Moreover, the toxicity effects of the FA-β-CD/DOX@Cu2+@GA@Fe3O4 on 3T3 cells and 4T1 cells were measured by the MTT method, and it was found that it displayed low cytotoxicity against 3T3 cells and had a stronger effect on killing 4T1 cells than DOX alone. The results also showed that the Cu2+-based coordination polymers had a significant ability to deplete GSH and generate ROS. It could be concluded that the introduction of Cu2+ not only facilitated the assembly of nanocomplexes, but also successfully enhanced the anti-tumor effect, making FA-β-CD@Cu2+@GA@Fe3O4 a potential nanoplatform for effectively mediating combined chemotherapy and chemokinetic therapy for tumors. All these characteristics verified the great potential of FA-β-CD/DOX@Cu2+@GA@Fe3O4 in multipurpose smart drug delivery systems, accelerating the application range of metal-polymer-coordinated nanocomplexes in biomedical fields.

Study on Doxorubicin Loading on Differently Functionalized Iron Oxide Nanoparticles: Implications for Controlled Drug-Delivery Application

Nanoplatforms applied for the loading of anticancer drugs is a cutting-edge approach for drug delivery to tumors and reduction of toxic effects on healthy cells. In this study, we describe the synthesis and compare the sorption properties of four types of potential doxorubicin-carriers, in which iron oxide nanoparticles (IONs) are functionalized with cationic (polyethylenimine, PEI), anionic (polystyrenesulfonate, PSS), and nonionic (dextran) polymers, as well as with porous carbon. The IONs are thoroughly characterized by X-ray diffraction, IR spectroscopy, high resolution TEM (HRTEM), SEM, magnetic susceptibility, and the zeta-potential measurements in the pH range of 3-10. The degree of doxorubicin loading at pH 7.4, as well as the degree of desorption at pH 5.0, distinctive to cancerous tumor environment, are measured. Particles modified with PEI were shown to exhibit the highest loading capacity, while the greatest release at pH 5 (up to 30%) occurs from the surface of magnetite decorated with PSS. Such a slow release of the drug would imply a prolonged tumor-inhibiting action on the affected tissue or organ. Assessment of the toxicity (using Neuro2A cell line) for PEI- and PSS-modified IONs showed no negative effect. In conclusion, the preliminary evaluation of the effects of IONs coated with PSS and PEI on the rate of blood clotting was carried out. The results obtained can be taken into account when developing new drug delivery platforms.

Magnetite and bismuth sulfide Janus heterostructures as radiosensitizers for in vivo enhanced radiotherapy in breast cancer

Janus heterostructures based on bimetallic nanoparticles have emerged as effective radiosensitizers owing to their radiosensitization capabilities in cancer cells. In this context, this study aims at developing a novel bimetallic nanoradiosensitizer, Bi₂S₃-Fe₃O₄, to enhance tumor accumulation and promote radiation-induced DNA damage while reducing adverse effects. Due to the presence of both iron oxide and bismuth sulfide metallic nanoparticles in these newly developed nanoparticle, strong radiosensitizing capacity is anticipated through the generation of reactive oxygen species (ROS) to induce DNA damage under X-Ray irradiation. To improve blood circulation time, biocompatibility, colloidal stability, and tuning surface functionalization, the surface of Bi₂S₃-Fe₃O₄ bimetallic nanoparticles was coated with bovine serum albumin (BSA). Moreover, to achieve higher cellular uptake and efficient tumor site specificity, folic acid (FA) as a targeting moiety was conjugated onto the bimetallic nanoparticles, termed Bi₂S₃@BSA-Fe₃O₄-FA. Biocompatibility, safety, radiation-induced DNA damage by ROS activation and generation, and radiosensitizing ability were confirmed via in vitro and in vivo assays. The administration of Bi₂S₃@BSA-Fe₃O₄-FA in 4T1 breast cancer murine model upon X-ray radiation revealed highly effective tumor eradication without causing any mortality or severe toxicity in healthy tissues. These findings offer compelling evidence for the potential capability of Bi₂S₃@BSA-Fe₃O₄-FA as an ideal nanoparticle for radiation-induced cancer therapy and open interesting avenues of future research in this area.

Facile Synthesis of Fe3O4@Au/PPy-DOX Nanoplatform with Enhanced Glutathione Depletion and Controllable Drug Delivery for Enhanced Cancer Therapeutic Efficacy

The complex physiological environment and inherent self-healing function of tumors make it difficult to eliminate malignant tumors by single therapy. In order to enhance the efficacy of antitumor therapy, it is significant and challenging to realize multi-mode combination therapy by utilizing/improving the adverse factors of the tumor microenvironment (TME). In this study, a novel Fe₃O₄@Au/PPy nanoplatform loaded with a chemotherapy drug (DOX) and responsive to TME, near-infrared (NIR) laser and magnetic field was designed for the combination enhancement of eliminating the tumor. The Fe²⁺ released at the low pH in TME can react with endogenous H₂O₂ to induce toxic hydroxyl radicals (·OH) for chemodynamic therapy (CDT). At the same time, the generated Fe³⁺ could deplete overexpressed glutathione (GSH) at the tumor site to prevent reactive oxygen species (ROS) from being restored while producing Fe²⁺ for CDT. The designed Fe₃O₄@Au/PPy nanoplatform had high photothermal (PT) conversion efficiency and photodynamic therapy (PDT) performance under NIR light excitation, which can promote CDT efficiency and produce more toxic ROS. To maximize the cancer-killing efficiency, the nanoplatform can be successfully loaded with the chemotherapeutic drug DOX, which can be efficiently released under NIR excitation and induction of slight acidity at the tumor site. In addition, the nanoplatform also possessed high saturation magnetization (20 emu/g), indicating a potential magnetic targeting function. In vivo and in vitro results identified that the Fe₃O₄@Au/PPy-DOX nanoplatform had good biocompatibility and magnetic-targeted synergetic CDT/PDT/PTT/chemotherapy antitumor effects, which were much better than those of the corresponding mono/bi/tri-therapies. This work provides a new approach for designing intelligent TME-mediated nanoplatforms for synergistically enhancing tumor therapy.

Marrying luminescent Au nanoclusters to TiO2 for visible-light-driven antibacterial application

Long-lasting yet visible-light-driven bacterial inhibition is highly desired for environmental protection and public health maintenance. However, conventional semiconductors such as titanium dioxide (TiO₂) are impotent for such antibacterial application due to their low utilization rate for visible light. Herein we report the design of a long-lasting yet visible-light-driven antibacterial agent based on marrying luminescent Au nanoclusters (Au NCs for short) to TiO₂ (TiO₂-NH₂@Au NCs). The as-obtained TiO₂-NH₂@Au NC antibacterial agent not only possesses superior utilization for visible light due to the participation of Au NCs as a good photosensitizer, but also has excellent separation efficacy of photogenerated carriers, thereby efficiently enhancing the generation of reactive oxygen species (ROS) for killing bacteria. Consequently, the TiO₂-NH₂@Au NCs display excellent antibacterial activity with good durability against both Gram-positive and Gram-negative bacteria such as Staphylococcus aureus (99.37%) and Escherichia coli (99.92%) under visible-light irradiation (λ ≥ 400 nm). This study is interesting because it provides a paradigm change in the design of long-lasting yet visible-light-driven NC-based antibacterial agents for diversified bactericidal applications.

Recent Advances in Functional Carbon Quantum Dots for Antitumour

Carbon quantum dots (CQDs) are an emerging class of quasi-zero-dimensional photoluminescent nanomaterials with particle sizes less than 10 nm. Owing to their favourable water dispersion, strong chemical inertia, stable optical performance, and good biocompatibility, CQDs have become prominent in biomedical fields. CQDs can be fabricated by “top-down” and “bottom-up” methods, both of which involve oxidation, carbonization, pyrolysis and polymerization. The functions of CQDs include biological imaging, biosensing, drug delivery, gene carrying, antimicrobial performance, photothermal ablation and so on, which enable them to be utilized in antitumour applications. The purpose of this review is to summarize the research progress of CQDs in antitumour applications from preparation and characterization to application prospects. Furthermore, the challenges and opportunities of CQDs are discussed along with future perspectives for precise individual therapy of tumours.

Self-assembled Au4Cu4/Au25 NCs@liposome tumor nanotheranostics with PT/fluorescence imaging-guided synergetic PTT/PDT

Exploring and developing a new type of nanoplatform with diagnosis and treatment to effectively cure tumors and reduce side effects has become a hot spot for researchers and is of great significance. Herein, a cancer theranostic nanoplatform with dual-imaging, dual-phototherapy and laser-responsiveness to tumor microenvironment was successfully assembled by liposome (Lip) co-loaded with oil-soluble Au₄Cu₄ nanoclusters (NCs) and water-soluble Au₂₅ NCs via a simple film hydration method and subsequent extraction process. The prepared Au₄Cu₄/Au₂₅@Lip nanoplatform with core-shell structure and about 50 nm of uniform sphere shape presented highly biocompatible, stability and passive targeting due to the enhanced permeability and retention (EPR) effect. Furthermore, the Lip composed of lecithin and cholesterol has good affinity with the cell membrane, which can realize the effective accumulation of photosensitizers at the tumor site, so that improving phototherapy effect and reducing the damage to normal tissue. The loaded oil-soluble Au₄Cu₄ NCs were firstly and pleasantly surprised to find possessed not only ideal photodynamic effect, but also preferable catalysis towards endogenous hydrogen peroxide (H₂O₂) decomposition to produce oxygen (O₂) for improving the tumor hypoxic environment besides the excellent photoluminescence ability while the water-soluble Au₂₅ NCs own outstanding photothermogenesis effect and also photoluminescence performance. The in vitro and in vivo experiment results proved that in the Au₄Cu₄/Au₂₅@Lip nanoplatform, the performances of both NCs were complementary, which presenting considerable photothermal/fluorescence imaging (PTI/FI)-guided synergistic photothermal therapy (PTT)/O₂-enhanced photodynamic therapy (PDT) effect for the tumor under the irradiation of near infrared (NIR) laser. This work provides a useful inspiration and paves a new way for the assembly of NCs or namomaterials with different properties into an integrated anti-tumor theranostic nanoplatform.

Preparation of responsive "dual-lock" nanoparticles and their application in collaborative therapy based on CuS coordination

It is difficult for drug delivery systems to release drugs as expected, often leading to undesired side effects. To solve this problem, a CuS@MSN/DOX@MnO₂@membrane (CMDMm) was reasonably designed. It was introduced to release the drug by a double response, similar to using two keys to open two locks at the same time for one door. CuS@MSN was used as a photothermal therapy (PTT) material and carrier, and then the surface of CuS@MSN/DOX was sealed by MnO₂ to prevent drug release in advance. MnO₂ could be reduced and degraded in a tumor microenvironment. It was applied in MR imaging due to the T₁ magnetism of Mn²⁺ following the reduction of MnO₂. Finally, the 4T1 cell membrane was extracted and coated onto the surface of CuS@MSN/DOX@MnO₂, which served as a target for 4T1 tumor cells. A noteworthy phenomenon was that the fluorescence of DOX was quenched by the coordination between DOX and CuS, and this greatly improved the interaction between DOX and CuS@MSN. However, the coordination was weakened when DOX was protonated in a tumor microenvironment (∼pH 5.0), leading to the release of DOX and fluorescence recovery. The drug release experiments showed that the release efficiency was higher at pH 5.0 with 10 mmol L^-1 GSH. Through in vitro laser confocal imaging, it was successfully observed that DOX was reliably released in specific tumor cells according to the fluorescence recovery, and that there was no leakage in other cells. In short, effective double response drug release was successfully confirmed.