Polymer Stabilized Fe3O4-Graphene as an Amphiphilic Drug Carrier for Thermo-Chemotherapy of Cancer

Bioinspired graphene-based metal oxide nanocomposites for photocatalytic and electrochemical performances: an updated review

Considering the rapidly increasing population, the development of new resources, skills, and devices that can provide safe potable water and clean energy remains one of the vital research topics for the scientific community. Owing to this, scientific community discovered such material for tackle this issue of environment benign, the new materials with graphene functionalized derivatives show significant advantages for application in multifunctional catalysis and energy storage systems. Herein, we highlight the recent methods reported for the preparation of graphene-based materials by focusing on the following aspects: (i) transformation of graphite/graphite oxide into graphene/graphene oxide via exfoliation and reduction; (ii) bioinspired fabrication or modification of graphene with various metal oxides and its applications in photocatalysis and storage systems. The kinetics of photocatalysis and the effects of different parameters (such as photocatalyst dose and charge-carrier scavengers) for the optimization of the degradation efficiency of organic dyes, phenol compounds, antibiotics, and pharmaceutical drugs are discussed. Further, we present a brief introduction on different graphene-based metal oxides and a systematic survey of the recently published research literature on electrode materials for lithium-ion batteries (LIBs), supercapacitors, and fuel cells. Subsequently, the power density, stability, pseudocapacitance charge/discharge process, capacity and electrochemical reaction mechanisms of intercalation, and conversion- and alloying-type anode materials are summarized in detail. Furthermore, we thoroughly distinguish the intrinsic differences among underpotential deposition, intercalation, and conventional pseudocapacitance of electrode materials. This review offers a meaningful reference for the construction and fabrication of graphene-based metal oxides as effective photocatalysts for photodegradation study and high-performance optimization of anode materials for LIBs, supercapacitors, and fuel cells.

Magnetic two-dimensional nanocomposites for multimodal antitumor therapy: a recent review

Magnetic two-dimensional nanocomposites (M2D NCs) that synergistically combine magnetic nanomedicine and 2D nanomaterials have emerged in multimodal antitumor therapy, attracting great interest in materials science and biomedical engineering. This review provides a summary of the recent advances of M2D NCs and their multimodal antitumor applications. We first introduce the design and fabrication of M2D NCs, followed by discussing new types of M2D NCs that have been recently reported. Then, a detailed analysis and discussions about the different types of M2D NCs are presented based on the structural categories of 2D NMs, including 2D graphene, transition metal dichalcogenides (TMDs), transition metal carbides/nitrides/carbonitrides (MXenes), black phosphorus (BP), layered double hydroxides (LDHs), metal organic frameworks (MOFs), covalent organic frameworks (COFs) and other 2D nanomaterials. In particular, we focus on the synthesis strategies, magnetic or optical responsive performance, and the versatile antitumor applications, which include magnetic hyperthermia therapy (MHT), photothermal therapy (PTT), photodynamic therapy (PDT), drug delivery, immunotherapy and multimodal imaging. We conclude the review by proposing future developments with an emphasis on the mass production and biodegradation mechanism of the M2D NCs. This work is expected to provide a comprehensive overview to researchers and engineers who are interested in such a research field and promote the clinical translation of M2D NCs in practical applications.

Effect of the Graphene- Ni/NiFe2O4 Composite on Bacterial Inhibition Mediated by Protein Degradation

Recent investigations have demonstrated that nickel ferrite nanoparticles and their derivatives have toxicity effects on bacterial cells. In this study, we have prepared nickel ferrite nanoparticles (Ni/NiFe₂O₄) and nickel/nickel ferrite graphene oxide (Ni/NiFe₂O₄-GO) nanocomposite and evaluated their toxic effects on E. coli cells ATCC 25922. The prepared nanomaterials were characterized using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and vibrating sample magnetometry techniques. The toxicity was evaluated using variations in cell viability, cell morphology, protein degradation, and oxidative stress. Ni/NiFe₂O₄-GO nanocomposites likewise prompt oxidative stress proved by the age of reactive oxygen species (ROS) and exhaustion of antioxidant glutathione. This is the first report indicating that Ni/NiFe₂O₄-GO nanocomposite-initiated cell death in E. coli through ROS age and oxidative stress.

Thermo- and Light-Responsive Polymer-Coated Magnetic Nanoparticles as Potential Drug Carriers

A series of thermo- and light-responsive copolymers of poly (N-isopropylacrylamide) (PNIPAM) and 6-[4-(4-methoxy phenyl azo)-phenoxyl-hexyl methacrylate) (AzoMA) (PNIPAM-b-PAzoMA) were synthesized via reversible addition–fragmentation chain transfer (RAFT) radical polymerization. The resulting copolymers had a narrow molecular weight distribution range of 1.06–1.24, in which Mn changed regularly with the monomer concentration. Subsequently, the diblock copolymers were successfully modified on the surface of iron oxide nanoparticles through the interaction between the chemical bonds to prepare Fe3O4@(PNIPAM-b-PAzoMA) nanoparticles. The size of fabricated nanoparticles with excellent thermo-sensitivity and photo-sensitivity was controlled at about 40–50 nm. Cell viability assays suggested that the nanoparticles showed no significant cytotoxicity and potential drug delivery in the tumor microenvironment.

The Fine-Tuned Release of Antioxidant from Superparamagnetic Nanocarriers under the Combination of Stationary and Alternating Magnetic Fields

Superparamagnetic magnetite nanoparticles (MNPs) with excellent biocompatibility and negligible toxicity were prepared by solvothermal method and stabilized by widely used and biocompatible polymer poly(ethylene glycol) PEG-4000 Da. The unique properties of the synthesized MNPs enable them to host the unstable and water-insoluble quercetin as well as deliver and localize quercetin directly to the desired site. The chemical and physical properties were validated by X-ray powder diffraction (XRPD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), superconducting quantum interference device (SQUID) magnetometer, FTIR spectroscopy and dynamic light scattering (DLS). The kinetics of in vitro quercetin release from MNPs followed by UV/VIS spectroscopy was controlled by employing combined stationary and alternating magnetic fields. The obtained results have shown an increased response of quercetin from superparamagnetic MNPs under a lower stationary magnetic field and s higher frequency of alternating magnetic field. The achieved findings suggested that we designed promising targeted quercetin delivery with fine-tuning drug release from magnetic MNPs.

Novel multi-stimuli responsive functionalized PEG-based co-delivery nanovehicles toward sustainable treatments of multidrug resistant tumor

The efficacy of ongoing anticancer treatment is often compromised by some barriers, such as low drug content, nonspecific release of drug delivery system, and multidrug resistance (MDR) effect of tumors. Herein, in the research a novel functionalized PEG-based polymer cystine-(polyethylene glycol)2-b-(poly(2-methacryloyloxyethyl ferrocenecarboxylate)2) (Cys-(PEG45)2-b-(PMAOEFC)2) with multi-stimuli sensitive mechanism was constructed, in which doxorubicin (DOX) was chemical bonded through Schiff base structure to provide acid labile DOX prodrug (DOX)2-Cys-(PEG45)2-b-(PMAOEFC)2. Afterwards, paclitaxel (PTX) and its diselenide bond linked PTX dimer were encapsulated into the prodrug through physical loading, to achieve pH and triple redox responsive (DOX)2-Cys-(PEG45)2-b-(PMAOEFC)2@PTX and (DOX)2-Cys-(PEG45)2-b-(PMAOEFC)2@PTX dimer with ultrahigh drugs content. The obtained nanovehicles could self-assemble into globular micelles with good stability based on fluorescence spectra and TEM observation. Moreover, there was a remarkable "reassembly-disassembly" behavior caused by phase transition of micelles under the mimic cancerous physiological environment. DOX and PTX could be on-demand released in acid and redox stress mode, respectively. Meanwhile, in vivo anticancer studies revealed the significant tumor inhibition of nanoformulas. This work offered facile strategies to fabricate drug nanaovehicles with tunable drug content and types, it has a profound significance in overcoming MDR effect, which provided more options for sustainable cancer treatment according to the desired drug dosage and the stage of tumor growth.

Fabrication of thermoresponsive magnetic micelles from amphiphilic poly(phenyl isocyanide) and Fe3O4 nanoparticles for controlled drug release and synergistic thermochemotherapy

The drug-loaded micelles self-assembled from co-poly(phenyl isocyanide), Fe₃O₄ and DOX demonstrated thermoresponsiveness and magnetic hyperthermia for synergistic thermochemotherapy.

Applications of Graphene and Graphene Oxide in Smart Drug/Gene Delivery: Is the World Still Flat?

Graphene, a wonder material, has made far-reaching developments in many different fields such as materials science, electronics, condensed physics, quantum physics, energy systems, etc. Since its discovery in 2004, extensive studies have been done for understanding its physical and chemical properties. Owing to its unique characteristics, it has rapidly became a potential candidate for nano-bio researchers to explore its usage in biomedical applications. In the last decade, remarkable efforts have been devoted to investigating the biomedical utilization of graphene and graphene-based materials, especially in smart drug and gene delivery as well as cancer therapy. Inspired by a great number of successful graphene-based materials integrations into the biomedical area, here we summarize the most recent developments made about graphene applications in biomedicine. In this paper, we review the up-to-date advances of graphene-based materials in drug delivery applications, specifically targeted drug/ gene delivery, delivery of antitumor drugs, controlled and stimuli-responsive drug release, photodynamic therapy applications and optical imaging and theranostics, as well as investigating the future trends and succeeding challenges in this topic to provide an outlook for future researches.

When polymers meet carbon nanostructures: expanding horizons in cancer therapy

The development of hybrid materials, which combine inorganic with organic materials, is receiving increasing attention by researchers. As a consequence of carbon nanostructures high chemical versatility, they exhibit enormous potential for new highly engineered multifunctional nanotherapeutic agents for cancer therapy. Whereas many groups are working on drug delivery systems for chemotherapy, the use of carbon nanohybrids for radiotherapy is rarely applied. Thus, nanotechnology offers a wide range of solutions to overcome the current obstacles of conventional chemo- and/or radiotherapies. Within this review, the structure and properties of carbon nanostructures (carbon nanotubes, nanographene oxide) functionalized preferentially with different types of polymers (synthetic, natural) are discussed. In short, synthesis approaches, toxicity investigations and anticancer efficacy of different carbon nanohybrids are described.

Drug-loaded dual targeting graphene oxide-based molecularly imprinted composite and recognition of carcino-embryonic antigen

Despite extensive research on functional graphene oxide for anticancer drug delivery, the sensitivity of traditional protein targeting ligands to the environment limits the practical applications of targeted drug delivery. A unique molecularly imprinted magnetic graphene oxide was used as a novel drug delivery system for the treatment of tumors. Molecularly imprinted polymers (MIPs) synthesized by molecular imprinting technology have the advantages of good stability against chemical and enzymatic attacks, high specificity for a target template, and resistance to harsh environments. In our work, the MIP was used for specificity to tumor cells with carcino-embryonic (CEA) tumor markers as the template, and dopamine as the functional monomer was grafted on boronic acid-functionalized magnetic graphene oxide. The structure of the nanoparticles was optimized and characterized in detail by vibrating sample magnetometry, X-ray diffraction analysis, UV-vis spectroscopy, and flow cytometry. The prepared polymer has magnetic properties, specific recognition to CEA, biocompatibility and pH sensitivity for drug delivery. Cell culture research was carried out on the tumor cells and normal cells. The composites exhibited dual targeting properties that not only magnetically target but also specifically increase the drug cytotoxicity to the tumor cells by selectively binding to CEA. On the basis of these results, this study developed a novel approach for targeting tumor cells for drug delivery without needing to modify the protein ligand.

In the research we designed a CEA-molecularly imprinted polymers using molecular imprinting technique with CEA tumor marker as template, boronic acid functionalized MGO as substrate for dual targeted delivery of drug to tumor cells.

Functionalization of Carbon Nanomaterials for Biomedical Applications

Over the past decade, carbon nanostructures (CNSs) have been widely used in a variety of biomedical applications. Examples are the use of CNSs for drug and protein delivery or in tools to locally dispense nucleic acids to fight tumor affections. CNSs were successfully utilized in diagnostics and in noninvasive and highly sensitive imaging devices thanks to their optical properties in the near infrared region. However, biomedical applications require a complete biocompatibility to avoid adverse reactions of the immune system and CNSs potentials for biodegradability. Water is one of the main constituents of the living matter. Unfortunately, one of the disadvantages of CNSs is their poor solubility. Surface functionalization of CNSs is commonly utilized as an efficient solution to both tune the surface wettability of CNSs and impart biocompatible properties. Grafting functional groups onto the CNSs surface consists in bonding the desired chemical species on the carbon nanoparticles via wet or dry processes leading to the formation of a stable interaction. This latter may be of different nature as the van Der Waals, the electrostatic or the covalent, the π-π interaction, the hydrogen bond etc. depending on the process and on the functional molecule at play. Grafting is utilized for multiple purposes including bonding mimetic agents such as polyethylene glycol, drug/protein adsorption, attaching nanostructures to increase the CNSs opacity to selected wavelengths or provide magnetic properties. This makes the CNSs a very versatile tool for a broad selection of applications as medicinal biochips, new high-performance platforms for magnetic resonance (MR), photothermal therapy, molecular imaging, tissue engineering, and neuroscience. The scope of this work is to highlight up-to-date using of the functionalized carbon materials such as graphene, carbon fibers, carbon nanotubes, fullerene and nanodiamonds in biomedical applications.

Biphasic Injectable Bone Cement with Fe3O4/GO Nanocomposites for the Minimally Invasive Treatment of Tumor-Induced Bone Destruction

Minimally invasive surgery will be gradually applied to the surgical treatment of bone tumors. One of the difficulties in the minimally invasive treatment of bone tumors is the lack of injectable materials that can be used to treat tumor-induced bone defects. Therefore, it is imperative to develop an injectable bone filler that can not only be injected into the defect site by minimally invasive methods to provide strong support and repair bone tissue but also inactivate residual tumor cells around the defect. To achieve this aim, in our study, for the first time, we doped Fe₃O₄/graphene oxide (GO) nanocomposites into α-tricalcium phosphate (α-TCP)/calcium sulfate (CS) biphasic bone cement to prepare an injectable magnetic bone cement (α-TCP/CS/Fe₃O₄/GO, αCFG), which can be applied in bone tumor minimally invasive surgery and fit ideally even if the area is irregular. The magnetothermal performance of the αCFG bone cement could be well adjusted by altering the content of Fe₃O₄/GO nanocomposites and the magnetic field parameters, but a 10 wt % Fe₃O₄/GO content formed the most stable bone cement with excellent magnetothermal performance. The αCFG bone cement not only promotes bone regeneration but also exhibits enhanced tumor treatment effects. Such multifunctional bone cement could provide a promising clinical strategy for the minimally invasive treatment of tumor-induced bone destruction.

Physically-triggered nanosystems based on two-dimensional materials for cancer theranostics

There is an increasing demand to develop effective methods for treating malignant diseases to improve healthcare in our society. Stimuli-responsive nanosystems, which can respond to internal or external stimuli are promising in cancer therapy and diagnosis due to their functionality and versatility. As a newly emerging class of nanomaterials, two-dimensional (2D) nanomaterials have attracted huge interest in many different fields including biomedicine due to their unique physical and chemical properties. In the past decade, stimuli-responsive nanosystems based on 2D nanomaterials have been widely studied, showing promising applications in cancer therapy and diagnosis, including phototherapies, magnetic therapy, drug and gene delivery, and non-invasive imaging. Here, we will focus our attention on the state-of-the-art of physically-triggered nanosystems based on graphene and two-dimensional nanomaterials for cancer therapy and diagnosis. The physical triggers include light, temperature, magnetic and electric fields.

Oxidized graphene nanoparticles as a delivery system for the pro-apoptotic sphingolipid C6 ceramide

Sphingolipids such as ceramide have attracted much attention as possible anticancer agents due to their potent pro-apoptotic effects. However, due to their extreme hydrophobicity, there is currently no clinically approved delivery method for in vivo use as a therapeutic agent. To this end, we have developed a novel method for loading the short-chain C₆ ceramide onto oxidized graphene nanoribbons (O-GNRs) and graphene nanoplatelets (GNPs). Mass spectrometry revealed loading efficiencies of 57% and 51.5% for C₆ ceramide onto O-GNRs and GNPs, respectively. The PrestoBlue viability assay revealed that 100 µg/mL of C₆ ceramide-loaded O-GNRs and C₆ ceramide-loaded GNPs reduced HeLa cell viability by approximately 93% and approximately 76%, respectively, compared to untreated HeLa cells, while equal concentrations of these nanoparticles without C₆ ceramide did not significantly reduce HeLa cell viability. We confirmed that this cytotoxicity was apoptotic in nature via capase-3 activity and Hoechst staining. Using live-cell confocal imaging with the fluorescent NBD-ceramide loaded on O-GNRs, we observed robust uptake into HeLa cells within 30 min while NBD-ceramide on its own was uptaken much more rapidly. Transmission electron microscopy confirmed that C₆ ceramide-loaded O-GNRs were actually entering cells. Taken together, these data show that O-GNRs are a promising delivery agent for ceramide. To our knowledge, this study is the first to use such a loading method. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 25-37, 2019.

Monitoring of topoisomerase (I) inhibitor camptothecin release from endogenous redox-stimulated GO-polymer hybrid carrier

We have developed endogenous redox-responsive polymer conjugated GO-based hybrid nanomaterials (GO-PEGssFol-CPT) for delivery of anticancer drug camptothecin (CPT) to the cancer cells. The synthesized intermediate (PEG_SSFol) and CPT loaded GO- PEG_SSFol were characterized using Fourier transform infrared spectroscopy (FTIR) and ¹H NMR. The morphological feature changes of TEM and AFM images have confirmed the loading of CPT on the nanocarrier and its release from the nanocarrier. The amount of CPT was loaded was found to be 14.2%. The extent of camptothecin (CPT) release from GO-BiotinPVA-CPT in the presence of different concentrations of glutathione (GSH) was monitored with the increase in the fluorescence intensity at λ_max 438 nm and UV-Vis absorbance at 366 nm. The time-dependent camptothecin (CPT) release was monitored in the presence of GSH. It was noticed that CPT was completely released from GO-PEGssFol-CPT within 45 min. This release process is free from interference by other ubiquitous analytes in the living system. The constant fluorescence intensity of GO-PEGssFol-CPT against acidic pH indicated that CPT would not be released in the extracellular region of cancer cells. Therefore, such delivery system could be used to prevent unwanted cytotoxicity to the healthy cells. The GO-PEGssFol-CPT showed higher antiproliferative activity against cervical cancer cells compared to the CPT. Thus, GO-PEGssFol-CPT can be a new material to deliver the anticancer drug to the target tumor region.

PEGylated mBPEI-rGO nanocomposites facilitate hepotocarcinoma treatment combining photothermal therapy and chemotherapy

Despite chemotherapy has been widely used for tumor therapy, the serious side effect is still a major challenge. Recently, two dimensional nanomaterial-based drug delivery systems have attracted wide concern due to their high drug loading and low side effect. In addition, some kinds of nanomaterials can directly act as a photosensitizer to induce cancer destruction. In this study, we developed a drug delivery system of mixture of high/low molecular weight branched polyethylenimine-polyethylene glycol-reduced graphene oxide (mBPEI-PEG-rGO) using reduced graphene oxide as matrix. A model drug of doxorubicin (DOX) was loaded on the nanocomposites with the efficiency of 81% and the release rate of more than 50% at acidic environment. In vitro experiments indicated that mBPEI-PEG-rGO-DOX with enhanced stability and biocompatibility efficiently delivered and released DOX into cells mainly through micropinocytosis and killed SMMC-7721 cells by inducing reactive oxygen species (ROS) and cell apoptosis. Furthermore, in vivo experiments indicated that the combination of intratumoral injection of mBPEI-PEG-rGO-DOX and local laser irradiation nearly ablated hepatocarcinoma. In conclusion, this new drug delivery system provided an alternative for combinational photothermal and chemotherapy against hepatocarcinoma.

Iron Oxide Nanoparticles for Biomedical Applications: A Perspective on Synthesis, Drugs, Antimicrobial Activity, and Toxicity

Medical applications and biotechnological advances, including magnetic resonance imaging, cell separation and detection, tissue repair, magnetic hyperthermia and drug delivery, have strongly benefited from employing iron oxide nanoparticles (IONPs) due to their remarkable properties, such as superparamagnetism, size and possibility of receiving a biocompatible coating. Ongoing research efforts focus on reducing drug concentration, toxicity, and other side effects, while increasing efficacy of IONPs-based treatments. This review highlights the methods of synthesis and presents the most recent reports in the literature regarding advances in drug delivery using IONPs-based systems, as well as their antimicrobial activity against different microorganisms. Furthermore, the toxicity of IONPs alone and constituting nanosystems is also addressed.

Advances on graphene-based nanomaterials for biomedical applications

Graphene-based nanomaterials, such as graphene oxide and reduced graphene oxide, have been attracting increasing attention in the field of biology and biomedicine over the past few years. Incorporation of these novel materials with drug, gene, photosensitizer and other cargos to construct novel delivery systems has witnessed rapid advance on the basis of their large surface area, distinct surface properties, excellent biocompatibility and pH sensitivity. Moreover, the inherent photothermal effect of these appealing materials enables them with the ability of killing targeting cells via a physical mechanism. Recently, more attentions have been attached to tissue engineering, including bone, neural, cardiac, cartilage, musculoskeletal, and skin/adipose tissue engineering, due to the outstanding mechanical strength, stiffness, electrical conductivity, various two-dimensional (2D) and three-dimensional (3D) morphologies of graphene-based nanomaterials. Herein, emerging applications of these nanomaterials in bio-imaging, drug/gene delivery, phototherapy, multimodality therapy and tissue engineering were comprehensively reviewed. Inevitably, the burgeon of this kind of novel materials leads to the endeavor to consider their safety so that this issue has been deeply discussed and summarized in our review. We hope that this review offers an overall understanding of these nanomaterials for later in-depth investigations.

Engineering Polyzwitterion and Polydopamine Decorated Doxorubicin-Loaded Mesoporous Silica Nanoparticles as a pH-Sensitive Drug Delivery

Multifunctional drug carriers have great applications in biomedical field. In this study, we introduced both polydopamine (PDA) and zwitterionic polymer of poly(3-(3-methacrylamidopropyl-(dimethyl)-ammonio)propane-1-sulfonate) (PSPP) onto the surface of mesoporous silica nanoparticles (MSNs) to develop a novel nanoparticle (MSNs@PDA-PSPP), which was employed as a new kind of drug carrier for the delivery of doxorubicin (DOX). The PDA coating, as a gatekeeper, could endow the drug carrier with pH-sensitive drug release performance. The outermost PSPP layer would make the drug carrier possess protein resistance performance. The chemical structure and properties were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS) and thermogravimetric analysis (TGA). MSNs@PDA-PSPP could keep good colloidal stability within 72 h in phosphate buffered saline (PBS) and protein solutions. Meanwhile, MSNs@PDA-PSPP exhibited a high drug loading for DOX. In vitro drug release experiments suggested MSNs-DOX@PDA-PSPP exhibited pH-dependent drug release behaviors. Besides, MSNs@PDA-PSPP had no cytotoxicity to human hepatocellular carcinoma cells (HepG2 cells) even at a concentration of 125 µg/mL. More importantly, cellular uptake and in vitro anticancer activity tests suggested that MSNs-DOX@PDA-PSPP could be taken up by HepG2 cells and DOX could be successfully released and delivered into the cell nuclei. Taken together, MSNs@PDA-PSPP have great potential in the biomedical field.

Combined Adsorption and Covalent Linking of Paclitaxel on Functionalized Nano-Graphene Oxide for Inhibiting Cancer Cells

Developing targeted delivery nanosystems for delivering chemotherapeutic anticancer drugs specifically to cancerous tissues with improvement in the specificity of drugs for different cancer cells can result in high therapeutic efficacy and low toxicity in healthy tissues. Herein, we proposed the synthesis of a multifunctional nanodelivery system, folic acid (FA) decorating nanographene oxide (nGO) functionalized with poly(ethylene glycol) (PEG), called pGO-FA, with good biocompatibility and good delivering performance of a hydrophobic water-insoluble anticancer drug of paclitaxel (PTX). 4-br-PEG-NH2, FA, and PTX were attached to PEG-functionalized nGO (pGO) through a combined chemical and physical force to form a nanosized complex, pGO-FA-PTX, defined as the nanodrug system. WST-8 assay in vitro illustrated that pGO-FA-PTX inhibited A2780 cells in a concentration-dependent manner. Cell viability was kept high to 60% when treated with 200 nM of free PTX. However, pGO-FA-PTX with the same dose of PTX (cell viability less than 30%) had double the cytotoxicity effect compared to free PTX. Furthermore, fluorescence observation demonstrated that pGO-FA-PTX exhibited an improved efficiency in killing A2780 cells due to the special affinity between FA and FA receptor, which has high expression in cancer cells. The strategy and method used in this study could be effective in improving both the bioavailability of PTX and therapy efficiency.

A nano-magnetic electrochemical sensor for the determination of mood disorder related substances

The simultaneous electrochemical detection of mood disorder related substances, such as amitriptyline, melatonin and tryptophan, was successfully achieved by using a novel nano-magnetic electrochemical sensor design, encompassing Fe₃O₄ nanoparticles decorated with carbon quantum dots (MagNPs/Cdots). The magnetic composite was characterized using HR-TEM microscopy, XRD and Raman spectroscopy, and was applied onto a glassy carbon electrode using a miniature neodymium magnet. The determination of amitriptyline, melatonin and tryptophan was performed by monitoring oxidation promoted by MagNPs/Cdots in BR-buffer at pH 3.0, which proceeded according to well-defined differential pulse voltammetry peaks, with detection limits of 5.9, 4.4 and 4.2 nmol L⁻¹, respectively. No significant interference was seen from biological interferents such as uric acid, ascorbic acid, dopamine, estriol and 17β-estradiol. The magnetic hybrid material was highly stable in solution, opening exciting opportunities for the development of low cost and practical electrochemical sensors for the determination of mood disorder related substances in real clinical samples.

The simultaneous electrochemical detection of mood disorder related substances, amitriptyline, melatonin and tryptophan, was successfully achieved by using a novel nano-magnetic electrochemical sensor decorated with carbon quantum dots (MagNPs/Cdots).

Construction of iron oxide nanoparticle-based hybrid platforms for tumor imaging and therapy

This review highlights the most recent progress in the construction of iron oxide nanoparticle-based hybrid platforms for tumor imaging and therapy.

Ligand-targeted theranostic nanomedicines against cancer

Nanomedicines have significant potential for cancer treatment. Although the majority of nanomedicines currently tested in clinical trials utilize simple, biocompatible liposome-based nanocarriers, their widespread use is limited by non-specificity and low target site concentration and thus, do not provide a substantial clinical advantage over conventional, systemic chemotherapy. In the past 20years, we have identified specific receptors expressed on the surfaces of tumor endothelial and perivascular cells, tumor cells, the extracellular matrix and stromal cells using combinatorial peptide libraries displayed on bacteriophage. These studies corroborate the notion that unique receptor proteins such as IL-11Rα, GRP78, EphA5, among others, are differentially overexpressed in tumors and present opportunities to deliver tumor-specific therapeutic drugs. By using peptides that bind to tumor-specific cell-surface receptors, therapeutic agents such as apoptotic peptides, suicide genes, imaging dyes or chemotherapeutics can be precisely and systemically delivered to reduce tumor growth in vivo, without harming healthy cells. Given the clinical applicability of peptide-based therapeutics, targeted delivery of nanocarriers loaded with therapeutic cargos seems plausible. We propose a modular design of a functionalized protocell in which a tumor-targeting moiety, such as a peptide or recombinant human antibody single chain variable fragment (scFv), is conjugated to a lipid bilayer surrounding a silica-based nanocarrier core containing a protected therapeutic cargo. The functionalized protocell can be tailored to a specific cancer subtype and treatment regimen by exchanging the tumor-targeting moiety and/or therapeutic cargo or used in combination to create unique, theranostic agents. In this review, we summarize the identification of tumor-specific receptors through combinatorial phage display technology and the use of antibody display selection to identify recombinant human scFvs against these tumor-specific receptors. We compare the characteristics of different types of simple and complex nanocarriers, and discuss potential types of therapeutic cargos and conjugation strategies. The modular design of functionalized protocells may improve the efficacy and safety of nanomedicines for future cancer therapy.

Stimuli responsive drug delivery systems based on nano-graphene for cancer therapy

Nano-graphene as a class of two-dimensional sp² carbon nanomaterial has attracted tremendous attentions in various fields in the past decade. Utilizing its unique physical and chemical properties, nano-graphene has also shown great promises in the area of biomedicine, for application in biosensing, imaging and therapy. In particular, with all atoms exposed on its surface, nano-graphene exhibits ultra-high surface area available for efficient binding/loading of various biomolecules of interests, and has been widely used as multifunctional nano-carriers for drug and gene delivery. In this review article, we will summarize the recent advances in the development of nano-graphene as stimuli-responsive nano-carriers for drug delivery, as well as the applications of these smart systems for cancer therapy.

Pharmacological evaluation of poly(3-methylthiophene) and its titanium(IV)phosphate nanocomposite: DNA interaction, molecular docking, and cytotoxic activity

Cancer and pathogenic microbial diseases have terribly affected human health over a longer period of time. In response to the increasing casualties due to cancer and microbial diseases, unique poly(3-methylthiophene) and poly(3-methylthiophene)-titanium(IV)phosphate composite were prepared via in-situ oxidative chemical polymerization in this work. The poly(3-methylthiophene) and poly(3-methylthiophene)-titanium(IV)phosphate composite were well characterized by Fourier transform infrared spectroscopy and field emission scanning electron microscopy. DNA binding studies by UV-Visible and fluorescence spectroscopic investigations indicated strong binding affinities of poly(3-methylthiophene) and poly(3-methylthiophene)-titanium(IV)phosphate nanocomposite; leading to structural damage of DNA. Poly(3-methylthiophene)-titanium(IV)phosphate nanocomposite showed stronger interactions with DNA as compared to poly(3-methylthiophene) and from dye displacement assay it was confirmed that mode of binding of both the formulations was intercalative. The antimicrobial screening revealed that polymer and its composite displayed stronger antibacterial effects than ampicillin against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhimurium. Besides, the poly(3-methylthiophene) and poly(3-methylthiophene)-titanium(IV)phosphate nanocomposite showed dose dependent effects towards estrogen receptor positive breast cancer (MCF-7) and estrogen receptor negative breast cancer (MDA-MB-231) cell lines; with poly(3-methylthiophene)-titanium(IV)phosphate nanocomposite showing better activities against both cell lines. In all in-vitro biological investigations, poly(3-methylthiophene)-titanium(IV)phosphate composite showed superior properties to that of the pure poly(3-methylthiophene), which encouraged us to suggest its potential as future therapeutic gear in drug delivery and other allied fields.

An arsenal of magnetic nanoparticles; perspectives in the treatment of cancer

Nanomedicine is an emerging field, which constitutes a new direction in the treatment of cancer. Magnetic nanoparticles (MNPs) can circumvent vascular tissue to concentrate at the site of the tumor. Under the influence of an external, alternating magnetic field, MNPs generate high temperatures within the tumor and ablate malignant cells while inflicting minimal damage to healthy host tissue. Due to their theranostic properties, they constitute a promising candidate for the treatment of cancer. A critical review of the type, size and therapeutic effect of different MNPs is presented, following an appraisal of the literature in the last 5 years. This is a multibillion dollar industry, with a few studies moving to clinical trials within the next 5 years.

Assessing Therapeutic Potential of Magnetic Mesoporous Nanoassemblies for Chemo-Resistant Tumors

Smart drug delivery system with strategic drug distribution is the future state-of-the-art treatment for any malignancy. To investigate therapeutic potential of such nanoparticle mediated delivery system, we examined the efficacy of dual drug-loaded, pH and thermo liable lipid coated mesoporous iron oxide-based magnetic nanoassemblies (DOX:TXL-LMMNA) in mice bearing both drug sensitive (A2780(S)) and drug resistant (A2780-CisR) ovarian cancer tumor xenografts. In presence of an external AC magnetic field (ACMF), DOX:TXL-LMMNA particles disintegrate to release encapsulated drug due to hyperthermic temperatures (41-45 ºC). In vivo bio distribution study utilizing the optical and magnetic properties of DOX:TXL-LMMNA particles demonstrated minimum organ specific toxicity. Noninvasive bioluminescence imaging of mice bearing A2780(S) tumors and administered with DOX-TXL-LMMNA followed by the application of ACMF revealed 65% less luminescence signal and 80% mice showed complete tumor regression within eight days. A six months follow-up study revealed absence of relapse in 70% of the mice. Interestingly, the A2780-CisR tumors which did not respond to drug alone (DOX:TXL) showed 80% reduction in luminescence and tumor volume with DOX:TXL-LMMNA after thermo-chemotherapy within eight days. Cytotoxic effect of DOX:TXL-LMMNA particles was more pronounced in A2780-CisR cells than in their sensitive counterpart. Thus these novel stimuli sensitive nanoassemblies hold great promise for therapy resistant malignancies and future clinical applications.

Supercritical synthesis of a magnetite-reduced graphene oxide hybrid with enhanced adsorption properties toward cobalt & strontium ions

The current study presents a supercritical synthesis of magnetite-reduced graphene oxide (M-RGO) in methanol media, in which Fe₃O₄ nanoparticles are simultaneously formed, surface modified and decorated on the surface of the reduced graphene oxide.

Facile synthesis of novel hydrophilic and carboxyl-amine functionalized superparamagnetic iron oxide nanoparticles for biomedical applications

We report a one-step facile synthesis of novel water-soluble and functionalized SPIONs, which could be promising candidates for cancer theranostics.

Recent advances in superparamagnetic iron oxide nanoparticles (SPIONs) for in vitro and in vivo cancer nanotheranostics

Recently superparamagnetic iron oxide nanoparticles (SPIONs) have been extensively used in cancer therapy and diagnosis (theranostics) via magnetic targeting, magnetic resonance imaging, etc. due to their remarkable magnetic properties, chemical stability, and biocompatibility. However, the magnetic properties of SPIONs are influenced by various physicochemical and synthesis parameters. So, this review mainly focuses on the influence of spin canting effects, introduced by the variations in size, shape, and organic/inorganic surface coatings, on the magnetic properties of SPIONs. This review also describes the several predominant chemical synthesis procedures and role of the synthesis parameters for monitoring the size, shape, crystallinity and composition of the SPIONs. Moreover, this review discusses about the latest developments of the inorganic materials and organic polymers for encapsulation of the SPIONs. Finally, the most recent advancements of the SPIONs and their nanopackages in combination with other imaging/therapeutic agents have been comprehensively discussed for their effective usage as in vitro and in vivo theranostic agents in cancer treatments.