Glutamic acid-coated Fe3O4 nanoparticles for tumor-targeted imaging and therapeutics

Amino acid coating of Fe3O4 surfaces under dry and hydrated conditions

This study explores the adsorption behavior of two amino acids (glycine - gly and glutamic acid - glu) as coating molecules for Fe3O4 nanoparticles to improve their biocompatibility for medical applications. Amino acid adsorption on the dry and hydrated reconstructed Fe3O4 (001) surface was investigated by means of quantum mechanical methods. According to Density Functional Theory (DFT) calculations (HSE06), the deprotonated form is favored over the zwitterion for both amino acids on the dry surface (by -0.14 and -0.59 eV for gly and glu, respectively), whereas the order is reversed under hydrated conditions (by +0.07 and +0.35 eV, for gly and glu, respectively). Given the small energy difference in the case of gly, deprotonated and zwitterionic adsorption modes are expected to compete and, probably, to coexist on the magnetite surface both under dry and hydrated conditions. Density Functional Tight-Binding (DFTB) method can only provide a qualitative energy order for amino acids adsorption on the dry magnetite surface due to excessive stabilization of the deprotonated adsorbed form (-0.54 and -1.24 eV for gly and glu, respectively). This overestimation favors the deprotonated form even under hydrated conditions (by -0.41 and -0.18 eV for gly and glu, respectively), which contradicts the more accurate DFT results. The approximate DFTB method presents limitations in correctly capturing the relative stability of different protonation states.

Molecular insight into the role of benzotriazole nanocapsule to deliver anticancer drug in smart drug delivery system

The use of nanomaterials as drug delivery systems is an area of interest for various anticancer drugs, aiming to minimize their side effects while ensuring they reach the target site effectively. In the current study, Benzotriazole capsule as drug delivery system for cyclophosphamide (CP) and gemcitabine (GB) drugs adsorption is explored. Various electronic and structural parameters shows that both drugs have good interaction with nanocapsule and can be carried to the target site easily. The calculated binding energies of drug@Capsule complexes are in the range of -43.34 and - 56.64 kcal/mol, which shows stronger interaction of drug molecules with nanocapsule. The noncovalent interactions between CP, GB and capsule are confirmed through QTAIM and NCI analyses. NBO analysis is used to understand the shifting of electron density, which shifts from drug to surface. FMO analysis is performed to estimate the perturbations in the electronic parameters upon complexation, which reveals reduction in the EH-L gap. Moreover, pH effect and dipole moment analysis are performed to get insight into the drug release mechanism. Dipole moment values indicate that nanocapsule can effectively release CP drug on a target site. The findings suggest that benzotriazole capsule surface is highly selective toward CP and GB.

Different conjugates of Fe3O4 nanoparticles, drug, and dye: optical and magnetic properties for in vivo bimodal imaging

Bioimaging is very important in medicine, especially in cancer diagnosis and treatment. In this study, we determined the impact of different components on the optical and magnetic properties of various conjugates. The three components, i.e., Fe3O4 nanoparticles (NPs), drug (doxorubicin - Dox), and dye (Cyanine 5.5 - Cy 5.5), were incorporated to form the four conjugates of A1 (Fe3O4-Cy 5.5), A2 (Fe3O4-Dox), A3 (Fe3O4-Cy 5.5-Dox), and A4 (Cy 5.5-Dox). The conjugates were characterized by DLS, UV-Vis spectra, fluorescence spectra, VSM, XRD, and TEM methods. After that, in vitro near-infrared (NIR) fluorescence imaging and magnetic resonance imaging (MRI) experiments were carried out to determine the conjugate suitable for bimodal imaging. The results show that A3 exhibits the highest quantum yield and radiance ratio and also has the highest ratio of r 2/r 1. The in vivo MRI and NIR fluorescent imaging results of CT26-bearing mice injected with A3 conjugates prove that the conjugate has potential in bimodal cancer imaging applications.

Upcycling hazardous waste into high-performance Ni/η-Al2O3 catalysts for CO2 methanation

Transforming hazardous and difficult-to-process waste materials, like spent Ni-MH batteries and aluminium foil, into nanocatalysts (NCts) provides a sustainable solution for resource management and reducing environmental impact. This study demonstrates a novel approach by extracting nickel sulfate (NiSO4·xH2O) from battery waste and subsequently converting it into Ni(OH)2 hydrogel precursors using l-glutamic acid. Waste aluminium foil was processed into alumina (Al2O3), and combined with Ni(OH)2 to synthesize Ni/η-Al2O3 NCts with 4% and 8% Ni loading. Characterization through XRD/SAED, STEM/EFTEM, and EELS revealed a disordered cubic structure of η-Al2O3, with well-dispersed Ni particles, making it effective for CO2 hydrogenation. The 8-Ni/η-Al2O3 exhibited the best catalytic performance, with CH4 selectivity of 99.8% and space time yield (STY) of 80.3 mmolCH4 gcat -1 h-1 at 400 °C. The CO2 methanation mechanism over Ni/η-Al2O3 NCts was further explored using operando DRIFTS aligned with GC + MS. The operando investigation suggested a preferential associative CO2 methanation pathway, involving sequential adsorption and hydrogenation of CO2 to hydrogen carbonates on Ni/η-Al2O3, and their transformation into formate and methoxy intermediates leading to methane. Finally, to complete the upcycling/recycling loop, the spent Ni/η-Al2O3 NCts were recycled into Ni and Al precursors. These findings underscore the potential of upcycling waste materials for synthesizing sustainable, high-performance NCts, and offer insights into the CO2 methanation mechanism.

Fluorescence tunable carbon dots for in vitro nuclear dynamics and gastrointestinal imaging in live zebrafish and their in vivo toxicity evaluation by cardio-craniofacial disfunction assessment

Sub-cellular organelle anomalies are frequently observed in diseases such as cancer. Early and precise diagnosis of these alterations can be crucial for patient outcomes. However, current diagnostic tools using conventional organic dyes or metal quantum dots face limitations, including poor biocompatibility, stringent storage conditions, limited solubility in aqueous media, and slow staining speeds. These challenges underscore the need for safer, more effective diagnostic and therapeutic solutions. In these aspects, we have developed highly photostable, biocompatible, water-dispersible carbon dots (TNCDs) with an average size of 5.5 nm using tartaric acid and ethylenediamine via a hydrothermal route. The synthesized TNCDs have shown bright blue fluorescence under the irradiation of UV-light at an excitation wavelength of 365 nm. They exhibit a quantum yield (QY) of 25.1% with maximum emission at 390 nm. A nice tri-exponential fitting of the decay curve with characteristic lifetimes of 1.52 ns, 3.05 ns and 6.11 ns for TNCDs was obtained. In vitro studies demonstrated that TNCDs have high biocompatibility (20 μg ml-1) with almost 100% cell viability and excellent nucleus targeting and staining capabilities with low background interference (with 10-12 times enhancement in fluorescence intensity). Additionally, if tagged with photosensitizers or radionuclides, TNCDs can serve as therapeutic agents in photodynamic therapy against cancer cells. Importantly, TNCDs exhibited negligible toxicity in developing zebrafish even at high concentrations (up to 400 mg L-1) as investigated by cardio and craniofacial disfunction assessment. Live organism imaging revealed that TNCDs produced aggregation-induced strong and specific green fluorescence in the gut of zebrafish larvae even at low concentrations, indicating their potential for nucleus staining and gut-specific optical imaging (at 50 mg L-1). Thus, our TNCDs represent a robust nanoplatform for cellular and whole-organism fluorescence imaging, offering both diagnostic and therapeutic potential.

Synthesis of platinum nanoparticles functionalized with glutamine and conjugated with thiosemicarbazone and their cytotoxic effects on MDA-MB-231 breast cancer cell line and evaluation of CASP-8 gene expression

Breast cancer (BC) is the most prevalent form of cancer among women and is a major contributor to cancer-related fatalities. Nanotechnology has provided novel approaches to drug delivery to cancer cells. In this work, we synthesized platinum (Pt) nanoparticles, functionalized them with glutamine, conjugated them with thiosemicarbazone (TSC), and characterized their anticancer effects on the MDA-MB-231 breast cancer cell line. Characteristics of the nanoparticles were assessed by FT-IR, XRD, EDS mapping, SEM, TEM, DLS, and zeta potential measurement. Cell viability was characterized by MTT assay, and cell necrosis/apoptosis levels were determined by flow cytometry. The expression level of the CASP-8 gene was investigated by real-time PCR. Pt@Gln-TSC nanoparticles are spherical, 20-70 nm in diameter in dry form, 662 nm after hydration, and their zeta potential was - 6.6 mV. The 50% inhibitory concentration (IC50) for MDA-MB-231 (breast cancer) and HDF (normal) cell lines was 170 and 348µg/ml, respectively. Also, the IC50 of oxaliplatin drug and TSC on MDA-MB-231 cells was 184 µg/ml and 307 µg/ml, respectively. Treatment with Pt@Gln-TSC nanoparticles caused an increase in cell necrosis and primary apoptosis and elevated the expression of the CASP-8 gene by 2.54 folds. This study shows that Pt@Gln-TSC nanoparticles are significantly more toxic to breast cancer cells than to normal cells and can inhibit MDA-MB-231 cells by activating extrinsic apoptosis.

Aluminum phthalocyanine tetrasulfonate conjugated to surface-modified Iron oxide nanoparticles as a magnetic targeting platform for photodynamic therapy of Ehrlich tumor-bearing mice

BACKGROUND

Photodynamic therapy (PDT) is a targeted treatment option for cancers that are non-responding to ordinary anticancer therapies. It involves activating a photosensitizer with a light source of a specific wavelength to destroy targeted cells and their surrounding vasculature. Aluminum phthalocyanine tetra sulfonate (AlPcS4) has gained attention as a second-generation photosensitizer for its strong absorption in the red-light region. AlPcS4 can be conjugated to magnetic iron oxide nanoparticles (IONs) to provide targeted drug delivery to the tumor cells while reducing its undesired effect on healthy tissues in other body parts.

METHODS

Magnetic glutamine functionalized iron oxide nanocomposites loaded with AlPcS4 (IONs-NH2-AlPcS4) were synthesized via the co-precipitation method. The conjugate (IONs-NH2-AlPcS4) was characterized by TEM, Zeta potential, DLS, FTIR, and UV-VIS absorption spectroscopy. Furthermore, its photodynamic activity was investigated using albino mice with induced Ehrlich solid tumors.

RESULTS

AlPcS4 was successfully conjugated to IONs-NH2 with a high loading efficiency of 54±2%. The synthesized conjugate exhibited a spherical shape, with 7 ± 2 nm particle size. The In vivo experiment revealed that the albino mice with induced Ehrlich solid tumor that were treated by combined PDT and magnetic targeting conjugate exhibited significant tumor regression and notably higher levels of necrotic tissue compared to the animals in other groups.

CONCLUSION

PDT mediated by magnetic targeting significantly inhibited tumor growth with minimal adverse effects, indicating its great potential as a promising strategy for solid cancer treatment.

Recent progress and current status of surface engineered magnetic nanostructures in cancer theranostics

Cancer theranostic is the combination of diagnosis and therapeutic modalities for cancer treatment. It realizes a more flexible, precise and non-invasive treatment of patients. In this aspect, magnetic nanostructures (MNSs) have gained paramount importance and revolutionized the cancer management due to their unique physicochemical properties and inherent magnetic characteristics. MNSs have amazing theranostic ability starting from drug delivery to magnetic hyperthermia and magnetic resonance imaging to multimodal imaging in association with radioisotopes or fluorescent probes. Precise regulation over the synthetic process and their consequent surface functionalization makes them even more fascinating. The ultimate goal is to develop a platform that combines multiple diagnostic and therapeutic functionalities based on MNSs. This perspective has provided an overview of the state-of-art of theranostic applications of MNSs. Special emphasis has been dedicated towards the importance of synthetic approaches of MNSs as well as their subsequent surface engineering and integration with biological/therapeutic molecules that decide the final outcomes of the efficacy of MNSs in theranostic applications. Moreover, the recent advancements, opportunities and allied challenges towards clinical applications of MNSs in cancer management have been demonstrated.

pH-Responsive magnetic nanocarriers for chelator-free bimodal (MRI/SPECT-CT) image-guided chemo-hyperthermia therapy in human breast carcinoma

Although chemotherapy with magnetic nanocarriers has witnessed significant advancement in the field of cancer treatment, multimodal diagnosis and combinatorial therapy using a single nanoplatform will have much better efficacy in achieving superior results. Herein, we constructed a smart theranostic system by combining pH-sensitive tartaric acid-stabilized Fe3O4 magnetic nanocarriers (TMNCs) with SPECT imaging and a chemotherapeutic agent for image-guided chemo-hyperthermia therapy. The carboxyl-enriched exteriors of TMNCs provided sites for the conjugation of a chemotherapeutic drug (doxorubicin hydrochloride, DOX) and radiolabeling (141Ce). The usage of 145.4 keV gamma rays made this platform an ideal choice for in vivo SPECT-CT imaging, showing the retention of the nanoformulation in the tumor site even after 28 days. Further, TMNCs showed a very high transverse relaxation rate (r2) of 171 mM-1 s-1, which is higher than that of clinically approved magnetic resonance imaging (MRI) contrast agents such as ferumoxtran (65 mM-1 s-1) and ferumoxides (120 mM-1 s-1). Further, the developed drug-loaded hybrid platform showed significantly higher cytotoxicity towards breast cancer cells, which was augmented by in vitro magnetic hyperthermia. Bright-field microscopy and cell cycle analysis suggested that cell death occurred through induction of G2-M arrest and subsequent apoptosis. These findings clearly suggest the potential of the developed hybrid nanoplatform for image-guided combination therapy.

Improving enzyme immobilization: A new carrier-based magnetic polymer for enhanced covalent binding of laccase enzyme

In the quest for effective enzyme immobilization methods, this study focuses on synthesizing carrier-based magnetic polymer to enhance the covalent binding of T. versicolor laccase. Utilizing chitosan (CS) and alginate (ALG) composites, modified with Fe3O4 magnetic nanoparticles (MNPs), we aimed to improve the enzyme's stability, reusability, and performance under varying conditions. The ionic gelation method was employed to prepare CS-ALG and CS-ALG-Fe3O4 MNPs composites, resulting in an 84% and 91% immobilization efficiency. The immobilized enzyme demonstrated superior thermal stability, retaining 48 % activity for CS-ALG-laccase and 67 % for CS-ALG-Fe3O4 MNPs-laccase at 70 °C, compared to 29 % for the free enzyme. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy were used to characterize the composites, revealing significant morphological changes and successful enzyme integration. Kinetic studies indicated that immobilization increased the Vmax to 141 μmol/min for CS-ALG-laccase and 111 μmol/min for CS-ALG-Fe3O4 MNPs-laccase, while slightly reducing substrate affinity (Km) to 1.42 mM-1 and 1.32 mM-1, respectively. The immobilized laccase retained higher activity after ten reaction cycles (81 % activity for CS-ALG-Fe3O4 MNPs-laccase) and during prolonged storage (75 % activity retention), showcasing its potential for industrial applications. Additionally, the enzyme exhibited increased resistance to various organic solvents, enhancing its practical utility.

pH-mediated potentiation of gallium nitrate against Pseudomonas aeruginosa

The emergence of multidrug-resistant Pseudomonas aeruginosa isolates is a growing concern for public health, necessitating new therapeutic strategies. Gallium nitrate [Ga(NO3)3], a medication for cancer-related hypercalcemia, has attracted great attention due to its ability to inhibit P. aeruginosa growth and biofilm formation by disrupting iron metabolism. However, the antibacterial efficacy of Ga(NO3)3 is not always satisfactory. It is imperative to investigate the factors that affect the bactericidal effects of Ga(NO3)3 and to identify new ways to enhance its efficacy. This study focused on the impact of pH on P. aeruginosa resistance to Ga(NO3)3, along with the underlying mechanism. The results indicate that acidic conditions could increase the effectiveness of Ga(NO3)3 against P. aeruginosa by promoting the production of pyochelin and gallium uptake. Subsequently, using glutamic acid, a clinically compatible acidic amino acid, the pH was significantly lowered and enhanced the bactericidal and inhibitory efficacy of Ga(NO3)3 against biofilm formation by P. aeruginosa, including a reference strain PA14 and several multidrug-resistant clinical isolates. Furthermore, we used an abscess mouse model to evaluate this combination in vivo; the results show that the combination of glutamic acid and Ga(NO3)3 significantly improved P. aeruginosa clearance. Overall, the present study demonstrates that acidic conditions can increase the sensitivity of P. aeruginosa to Ga(NO3)3. Combining glutamic acid and Ga(NO3)3 is a potential strategy for the treatment of P. aeruginosa infections.

Surface Engineering of Magnetic Iron Oxide Nanoparticles for Breast Cancer Diagnostics and Drug Delivery

Data published in 2020 by the International Agency for Research on Cancer (IARC) of the World Health Organization show that breast cancer (BC) has become the most common cancer globally, affecting more than 2 million women each year. The complex tumor microenvironment, drug resistance, metastasis, and poor prognosis constitute the primary challenges in the current diagnosis and treatment of BC. Magnetic iron oxide nanoparticles (MIONPs) have emerged as a promising nanoplatform for diagnostic tumor imaging as well as therapeutic drug-targeted delivery due to their unique physicochemical properties. The extensive surface engineering has given rise to multifunctionalized MIONPs. In this review, the latest advancements in surface modification strategies of MIONPs over the past five years are summarized and categorized as constrast agents and drug delivery platforms. Additionally, the remaining challenges and future prospects of MIONPs-based targeted delivery are discussed.

Efficient delivery of anticancer drugs using functionalized-Ag-decorated Fe3O4@SiO2 nanocarrier with folic acid and β-cyclodextrin

Nanocarrier surface functionalization has been widely regarded as a promising approach for achieving precise and targeted drug delivery systems. In this work, the fabrication of functionalized-Ag-decorated Fe3O4@SiO2 (Fe3O4@SiO2-Ag) nanocarriers with folic acid (FA) and β-cyclodextrin (BCD) exhibit a remarkable capacity for delivering two types of anticancer drugs, i.e., doxorubicin (DOX) and epirubicin (EPI), into cancer cells. The effective functionalization of Fe3O4@SiO2-Ag nanoparticles has been achieved through the use of cysteine (Cys) as an anchor for attaching FA and BCD via EDC-NHS coupling and Steglich esterification methods, respectively. The findings indicate that surface functionalization had no significant impact on the physicochemical characteristics of the nanoparticles. However, it notably affected DOX and EPI loading and release efficiency. The electrostatic conjugation of DOX/EPI onto the surface of Fe3O4@SiO2-Ag/Cys/FA and Fe3O4@SiO2-Ag/Cys/BCD exhibited maximum loading efficiency of 50-60% at concentration ratio of DOX/EPI to nanoparticles of 1:14. These nanocarriers also achieved an 40-47% DOX/EPI release over 36 days. Furthermore, the drug-loaded functionalized-nanocarrier showed cytotoxic effects on SK-MEL-2 cells, as demonstrated by an in vitro MTT assay. This suggests that the as-prepared functionalized-nanoparticles have promise as a carrier for the efficient anticancer drugs.

Recent advances in nanomedicine for metabolism-targeted cancer therapy

Metabolism denotes the sum of biochemical reactions that maintain cellular function. Different from most normal differentiated cells, cancer cells adopt altered metabolic pathways to support malignant properties. Typically, almost all cancer cells need a large number of proteins, lipids, nucleotides, and energy in the form of ATP to support rapid division. Therefore, targeting tumour metabolism has been suggested as a generic and effective therapy strategy. With the rapid development of nanotechnology, nanomedicine promises to have a revolutionary impact on clinical cancer therapy due to many merits such as targeting, improved bioavailability, controllable drug release, and potentially personalized treatment compared to conventional drugs. This review comprehensively elucidates recent advances of nanomedicine in targeting important metabolites such as glucose, glutamine, lactate, cholesterol, and nucleotide for effective cancer therapy. Furthermore, the challenges and future development in this area are also discussed.

Targeted drug delivery systems for matrix metalloproteinase-responsive anoparticles in tumor cells: A review

Nanodrug delivery systems based on tumor microenvironment responses have shown excellent performance in tumor-targeted therapy, given their unique targeting and drug-release characteristics. Matrix metalloproteinases (MMPs) have been widely explored owing to their high specificity and expression in various tumor microenvironments. The design of an enzyme-sensitive nanodelivery system using MMPs as targeted receptors could markedly improve the performance of drug targeting. The current review focuses on the development and application of MMP-responsive drug carriers, and summarizes the classification of single- and multi-target nanocarriers based on their MMP responsiveness. The potential applications and challenges of this nanodrug delivery system are discussed to provide a reference for designing high-performance nanodrug delivery systems.

Synergistic effects of multidrug/material combination deliver system for anti-mutidrug-resistant tumor

Multidrug resistance (MDR) is a public health issue of particular concern, for which nanotechnology-based multidrug delivery systems are considered among the most effective suppressive strategies for such resistance in tumors. However, for such strategies to be viable, the notable shortcomings of reduced loading efficiency and uncontrollable drug release ratio need to be addressed. To this end, we developed a novel "multidrug/material" co-delivery system, using d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS, P-gp efflux pump inhibitor) and poly(amidoamine) (PAMAM) to fabricate a precursor material with the properties of reversing MDR and having a long-cycle. Further, to facilitate multidrug co-delivery, we loaded doxorubicin(Dox) and curcumin(Cur, cardiotoxicity modifier and P-gp inhibitor) into PAMAM-TPGS nano-micelles respectively, and mixed in appropriate proportions. The multidrug/material co-delivery system thus obtained was characterized by high drug loading and a controllable drug release ratio in the physiological environment. More importantly, in vitro and in vivo pharmacodynamic studies indicated that the multidrug/material co-delivery system facilitated the reversal of MDR. Moreover, the system has increased anti-tumor activity and is biologically safe. We accordingly propose that the "multidrug/material" co-delivery system developed in this study could serve as a potential platform for reversing MDR and achieving safe and effective clinical treatment.

Nano-phototherapy: Favorable prospects for cancer treatment

Nanotechnology-based phototherapies have drawn interest in the fight against cancer because of its noninvasiveness, high flexibility, and precision in terms of cancer targeting and drug delivery based on its surface properties and size. Phototherapy has made remarkable development in recent decades. Approaches to phototherapy, which utilize nanomaterials or nanotechnology have emerged to contribute to advances around nanotechnologies in medicine, particularly for cancers. A brief overviews of the development of photodynamic therapy as well as its mechanism in cancer treatment is provided. We emphasize the design of novel nanoparticles utilized in photodynamic therapy while summarizing the representative progress during the recent years. Finally, to forecast important future research in this area, we examine the viability and promise of photodynamic therapy systems based on nanoparticles in clinical anticancer treatment applications and briefly make mention of the elimination of all reactive metabolites pertaining to nano formulations inside living organisms providing insight into clinical mechanistic processes. Future developments and therapeutic prospects for photodynamic treatments are anticipated. Our viewpoints might encourage scientists to create more potent phototherapy-based cancer therapeutic modalities. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

The Application of Nanotechnological Therapeutic Platforms against Gynecological Cancers

Gynecological cancers (GCs), ovarian, cervical, and endometrial/uterine cancers, are often associated with poor outcomes. Despite the development of several therapeutic modalities against GCs, the effectiveness of the current therapeutic approaches is limited due to their side effects, low therapeutic index, short halflife, and resistance to therapy. To overcome these limitations, nano delivery-based approaches have been introduced with the potential of targeted delivery, reduced toxicity, controlled release, and improved bioavailability of various cargos. This review summarizes the application of different nanoplatforms, such as lipid-based, metal- based, and polymeric nanoparticles, to improve the chemo/radio treatments of GC. In the following work, the use of nanoformulated agents to fight GCs has been mentioned in various clinical trials. Although nanosystems have their own challenges, the knowledge highlighted in this article could provide deep insight into translations of NPs approaches to overcome GCs.

Smart Magnetic Nanocarriers for Codelivery of Nitric Oxide and Doxorubicin for Enhanced Apoptosis in Cancer Cells

Extremely short half-life therapeutic molecule nitric oxide (NO) plays significant roles in the functioning of various physiological and pathological processes in the human body, whereas doxorubicin hydrochloride (DOX) is a clinically important anticancer drug widely used in cancer chemotherapy. Thus, the intracellular delivery of these therapeutic molecules is tremendously important to achieve their full potential. Herein, we report a novel approach for the development of highly water-dispersible magnetic nanocarriers for codelivery of NO and DOX. Primarily, bifunctional magnetic nanoparticles enriched with carboxyl and thiol groups were prepared by introducing cysteine onto the surface of citrate-functionalized Fe3O4 nanoparticles. DOX was electrostatically conjugated onto the surface of bifunctional nanoparticles via carboxyl moieties, whereas the thiol group was further nitrosated to provide NO-releasing molecules. The developed magnetic nanocarrier exhibited good aqueous colloidal stability, protein resistance behavior, and high encapsulation efficacy for NO (65.5%) and DOX (85%), as well as sustained release characteristics. Moreover, they showed superior cytotoxicity toward cancer (A549 and MCF-7) cells via apoptosis induction over normal (WI26VA4) cells. Specifically, we have developed magnetic nanocarriers having the capability of dual delivery of NO and DOX, which holds great potential for combinatorial cancer treatment.

Recent development of pH-responsive theranostic nanoplatforms for magnetic resonance imaging-guided cancer therapy

The acidic characteristic of the tumor site is one of the most well-known features and provides a series of opportunities for cancer-specific theranostic strategies. In this regard, pH-responsive theranostic nanoplatforms that integrate diagnostic and therapeutic capabilities are highly developed. The fluidity of the tumor microenvironment (TME), with its temporal and spatial heterogeneities, makes noninvasive molecular magnetic resonance imaging (MRI) technology very desirable for imaging TME constituents and developing MRI-guided theranostic nanoplatforms for tumor-specific treatments. Therefore, various MRI-based theranostic strategies which employ assorted therapeutic modes have been drawn up for more efficient cancer therapy through the raised local concentration of therapeutic agents in pathological tissues. In this review, we summarize the pH-responsive mechanisms of organic components (including polymers, biological molecules, and organosilicas) as well as inorganic components (including metal coordination compounds, metal oxides, and metal salts) of theranostic nanoplatforms. Furthermore, we review the designs and applications of pH-responsive theranostic nanoplatforms for the diagnosis and treatment of cancer. In addition, the challenges and prospects in developing theranostic nanoplatforms with pH-responsiveness for cancer diagnosis and therapy are discussed.

Hyaluronic acid mediated Fe3O4 nanocubes reversing the EMT through targeted cancer stem cell

Hepatocellular carcinoma (HCC) is one of the deadliest tumors in the world with a high rate of recurrence and metastasis. Therefore, the most pressing issue today is the development of new drugs, diagnostic and therapeutic approaches for effective cancer treatment. Cancer stem cells (CSCs) play a pivotal role in tumor recurrence, tumor resistance, and tumor metastasis, which provides a new perspective on the development of liver cancer. In the study, a high-temperature thermal breakdown approach was used to create composite magnetic nanocubes modified by polyethyleneimine (PEI) and hyaluronic acid (HA). The Fe₃O₄ nanocubes can recognize HCC stem cells via receptor-ligand binding of HA and CD44 (HA receptor). While loading a small molecule LDN193189 inhibited the expression of stemness-related genes OCT4 and Nanog. More crucially, the Fe₃O₄ nanocubes significantly suppressed HCC cell proliferation and migration by regulating the expression of epithelial-mesenchymal transition (EMT) process markers E-cadherin, Vimentin, and N-cadherin. Dual targeting using magnetic and receptor-mediated targeting improved the uptake of the drug delivery system. Our findings imply that the medication delivery method might be a potential therapeutic strategy for HCC.

Multifunctional nanoparticle for cancer therapy

Cancer is a complex disease associated with a combination of abnormal physiological process and exhibiting dysfunctions in multiple systems. To provide effective treatment and diagnosis for cancer, current treatment strategies simultaneously focus on various tumor targets. Based on the rapid development of nanotechnology, nanocarriers have been shown to exhibit excellent potential for cancer therapy. Compared with nanoparticles with single functions, multifunctional nanoparticles are believed to be more aggressive and potent in the context of tumor targeting. However, the development of multifunctional nanoparticles is not simply an upgraded version of the original function, but involves a sophisticated system with a proper backbone, optimized modification sites, simple preparation method, and efficient function integration. Despite this, many well-designed multifunctional nanoparticles with promising therapeutic potential have emerged recently. Here, to give a detailed understanding and analyzation of the currently developed multifunctional nanoparticles, their platform structures with organic or inorganic backbones were systemically generalized. We emphasized on the functionalization and modification strategies, which provide additional functions to the nanoparticle. We also discussed the application combination strategies that were involved in the development of nanoformulations with functional crosstalk. This review thus provides an overview of the construction strategies and application advances of multifunctional nanoparticles.

Effect of the Silica-Magnetite Nanocomposite Coating Functionalization on the Doxorubicin Sorption/Desorption

A series of new composite materials based on Fe3O4 magnetic nanoparticles coated with SiO2 (or aminated SiO2) were synthesized. It has been shown that the use of N-(phosphonomethyl)iminodiacetic acid (PMIDA) to stabilize nanoparticles before silanization ensures the increased content of a SiO2 phase in the Fe3O4@SiO2 nanocomposites (NCs) in comparison with materials obtained under similar conditions, but without PMIDA. It has been demonstrated for the first time that the presence of PMIDA on the surface of NCs increases the level of Dox loading due to specific binding, while surface modification with 3-aminopropylsilane, on the contrary, significantly reduces the sorption capacity of materials. These regularities were in accordance with the results of quantum chemical calculations. It has been shown that the energies of Dox binding to the functional groups of NCs are in good agreement with the experimental data on the Dox sorption on these NCs. The mechanisms of Dox binding to the surface of NCs were proposed: simultaneous coordination of Dox on the PMIDA molecule and silanol groups at the NC surface leads to a synergistic effect in Dox binding. The synthesized NCs exhibited pH-dependent Dox release, as well as dose-dependent cytotoxicity in in vitro experiments. The cytotoxic effects of the studied materials correspond to their calculated IC50 values. NCs with a SiO2 shell obtained using PMIDA exhibited the highest effect. At the same time, the presence of PMIDA in NCs makes it possible to increase the Dox loading, as well as to reduce its desorption rate, which may be useful in the design of drug delivery vehicles with a prolonged action. We believe that the data obtained can be further used to develop stimuli-responsive materials for targeted cancer chemotherapy.

New Insight into Assembled Fe3O4@PEI@Ag Structure as Acceptable Agent with Enzymatic and Photothermal Properties

Metal-based enzyme mimics are considered to be acceptable agents in terms of their biomedical and biological properties; among them, iron oxides (Fe₃O₄) are treated as basement in fabricating heterogeneous composites through variable valency integrations. In this work, we have established a facile approach for constructing Fe₃O₄@Ag composite through assembling Fe₃O₄ and Ag together via polyethyleneimine ethylenediamine (PEI) linkages. The obtained Fe₃O₄@PEI@Ag structure conveys several hundred nanometers (~150 nm). The absorption peak at 652 nm is utilized for confirming the peroxidase-like activity of Fe₃O₄@PEI@Ag structure by catalyzing 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H₂O₂. The Michaelis–Menten parameters (K_m) of 1.192 mM and 0.302 mM show the higher catalytic activity and strong affinity toward H₂O₂ and TMB, respectively. The maximum velocity (V_max) value of 1.299 × 10⁻⁷ M∙s⁻¹ and 1.163 × 10⁻⁷ M∙s⁻¹ confirm the efficiency of Fe₃O₄@PEI@Ag structure. The biocompatibility illustrates almost 100% cell viability. Being treated as one simple colorimetric sensor, it shows relative selectivity and sensitivity toward the detection of glucose based on glucose oxidase. By using indocyanine green (ICG) molecule as an additional factor, a remarkable temperature elevation is observed in Fe₃O₄@PEI@Ag@ICG with increments of 21.6 °C, and the absorption peak is nearby 870 nm. This implies that the multifunctional Fe₃O₄@PEI@Ag structure could be an alternative substrate for formatting acceptable agents in biomedicine and biotechnology with enzymatic and photothermal properties.

Enhancing the therapeutic efficacy of nanoparticles for cancer treatment using versatile targeted strategies

Poor targeting of therapeutics leading to severe adverse effects on normal tissues is considered one of the obstacles in cancer therapy. To help overcome this, nanoscale drug delivery systems have provided an alternative avenue for improving the therapeutic potential of various agents and bioactive molecules through the enhanced permeability and retention (EPR) effect. Nanosystems with cancer-targeted ligands can achieve effective delivery to the tumor cells utilizing cell surface-specific receptors, the tumor vasculature and antigens with high accuracy and affinity. Additionally, stimuli-responsive nanoplatforms have also been considered as a promising and effective targeting strategy against tumors, as these nanoplatforms maintain their stealth feature under normal conditions, but upon homing in on cancerous lesions or their microenvironment, are responsive and release their cargoes. In this review, we comprehensively summarize the field of active targeting drug delivery systems and a number of stimuli-responsive release studies in the context of emerging nanoplatform development, and also discuss how this knowledge can contribute to further improvements in clinical practice.

New Insights into Amino-Functionalization of Magnetic Nanoplatelets with Silanes and Phosphonates

Magnetic nanoplatelets (NPLs) based on barium hexaferrite (BaFe₁₂O₁₉) are suitable for many applications because of their uniaxial magneto-crystalline anisotropy. Novel materials, such as ferroic liquids, magneto-optic composites, and contrast agents for medical diagnostics, were developed by specific surface functionalization of the barium hexaferrite NPLs. Our aim was to amino-functionalize the NPLs’ surfaces towards new materials and applications. The amino-functionalization of oxide surfaces is challenging and has not yet been reported for barium hexaferrite NPLs. We selected two amine ligands with two different anchoring groups: an amino-silane and an amino-phosphonate. We studied the effect of the anchoring group, backbone structure, and processing conditions on the formation of the respective surface coatings. The core and coated NPLs were examined with transmission electron microscopy, and their room-temperature magnetic properties were measured. The formation of coatings was followed by electrokinetic measurements, infrared and mass spectroscopies, and thermogravimetric analysis. The most efficient amino-functionalization was enabled by (i) amino-silanization of the NPLs precoated with amorphous silica with (3-aminopropyl)triethoxysilane and (ii) slow addition of amino-phosphonate (i.e., sodium alendronate) to the acidified NPL suspension at 80 °C.

Functionalization of Fe3O4/rGO magnetic nanoparticles with resveratrol and in vitro DNA interaction

Based on the previous research, we found that the magnetic nanocomposite Fe₃O₄/rGO (reduced graphene oxide) has a good drug loading effect. Therefore, in this paper, we studied the positive role of Fe₃O₄/rGO as a drug carrier in the interaction between resveratrol (RES) and calf-thymus DNA (ct-DNA). The fluorescence experiment is used to evaluate by the Stern-Volmer equation, the quenching constant of RES - ct-DNA system with and without Fe₃O₄/rGO decreases with the increasing temperature. It was found the quenching mode of RES - ct-DNA and Fe₃O₄/rGO - RES - ct-DNA systems were all static quenching, but the binding constant of RES -ct-DNA increased from 4.14 ± 0.21 × 10⁴ L mol^-1 to 10.12 ± 0.02 × 10⁴ L mol^-1. It was found that Fe₃O₄/rGO formed a ternary complex with RES and ct-DNA by ultraviolet spectrum (UV-vis), resonance light scattering experiments (RLS) and scanning electron microscope (SEM). Meanwhile, Fourier transform infrared (FT-IR) and circular dichroism (CD) experiments show that Fe₃O₄/rGO and Fe₃O₄/rGO loaded with RES have effect on the secondary structure of ct-DNA and change the conformation of ct-DNA. On the cellular level, the comet assay shows that Fe₃O₄/rGO and Fe₃O₄/rGO - RES could not cause DNA strand break to the mouse hepatocytes after 24 co-incubation. These results confirm that Fe₃O₄/rGO nanocomposites have good application potential, which can be used as a good drug carrier in a wide range of therapeutic methods.

Amino Acid Complexes of Zirconium in a Carbon Composite for the Efficient Removal of Fluoride Ions from Water

Amino acid complexes of zirconia represent an entirely new class of materials that were synthesized and studied for the first time for the decontamination of fluoride ion containing aqueous solutions. Glutamic and aspartic acid complexes of zirconia assembled with thin carbon (stacked graphene oxide) platelets deriving from graphite oxide (GO) were synthesized by a two-step method to prepare adsorbents. The characterization of the complexes was carried out using infrared spectroscopy to determine the functional groups and the types of interaction between the composites and fluoride ions. To reveal the mechanisms and extent of adsorption, two types of batch adsorption measurements were performed: (i) varying equilibrium fluoride ion concentrations to construct adsorption isotherms at pH = 7 in the absence of added electrolytes and (ii) using fixed initial fluoride ion concentrations (10 mg/L) with a variation of either the pH or the concentration of a series of salts that potentially interfere with adsorption. The experimental adsorption isotherms were fitted by three different theoretical isotherm equations, and they are described most appropriately by the two-site Langmuir model for both adsorbents. The adsorption capacities of Zr-glutamic acid-graphite oxide and Zr-aspartic acid-graphite oxide are 105.3 and 101.0 mg/g, respectively. We found that two distinct binding modes are combined in the Zr-amino acid complexes: at low solution concentrations, F⁻ ions are preferentially adsorbed by coordinating to the surface Zr species up to a capacity of ca. 10 mg/g. At higher concentrations, however, large amounts of fluoride ions may undergo anion exchange processes and physisorption may occur on the positively charged ammonium moieties of the interfacially bound amino acid molecules. The high adsorption capacity and affinity of the studied dicarboxylate-type amino acids demonstrate that amino acid complexes of zirconia are highly variable materials for the safe and efficient capture of strong Lewis base-type ions such as fluoride.

Inspirations of Cobalt Oxide Nanoparticle Based Anticancer Therapeutics

Cobalt is essential to the metabolism of all animals due to its key role in cobalamin, also known as vitamin B12, the primary biological reservoir of cobalt as an ultra-trace element. Current cancer treatment strategies, including chemotherapy and radiotherapy, have been seriously restricted by their side effects and low efficiency for a long time, which urges us to develop new technologies for more effective and much safer anticancer therapies. Novel nanotechnologies, based on different kinds of functional nanomaterials, have been proved to act as effective and promising strategies for anticancer treatment. Based on the important biological roles of cobalt, cobalt oxide nanoparticles (NPs) have been widely developed for their attractive biomedical applications, especially their potential for anticancer treatments due to their selective inhibition of cancer cells. Thus, more and more attention has been attracted to the preparation, characterization and anticancer investigation of cobalt oxide nanoparticles in recent years, which is expected to introduce novel anticancer treatment strategies. In this review, we summarize the synthesis methods of cobalt oxide nanoparticles to discuss the advantages and restrictions for their preparation. Moreover, we emphatically discuss the anticancer functions of cobalt oxide nanoparticles as well as their underlying mechanisms to promote the development of cobalt oxide nanoparticles for anticancer treatments, which might finally benefit the current anticancer therapeutics based on functional cobalt oxide nanoparticles.

Recent advances in active targeting of nanomaterials for anticancer drug delivery

One of the challenges in cancer chemotherapy is the low target to non-target ratio of therapeutic agents which incur severe adverse effect on the healthy tissues. In this regard, nanomaterials have tremendous potential for impacting cancer therapy by altering the toxicity profile of the drug. Some of the striking advantages provided by the nanocarriers mediated targeted drug delivery are relatively high build-up of drug concentration at the tumor site, improved drug content in the formulation and enhanced colloidal stability. Further, nanocarriers with tumor-specific moieties can be targeted to the cancer cell through cell surface receptors, tumor antigens and tumor vasculatures with high affinity and accuracy. Moreover, it overcomes the bottleneck of aimless drug biodistribution, undesired toxicity and heavy dosage of administration. This review discusses the recent developments in active targeting of nanomaterials for anticancer drug delivery through cancer cell surface targeting, organelle specific targeting and tumor microenvironment targeting strategies. Special emphasis has been given towards cancer cell surface and organelle specific targeting as delivery of anticancer drugs through these routes have made paradigm change in cancer management. Further, the current challenges and future prospects of nanocarriers mediated active drug targeting are also demonstrated.

Human Cancer Cell Membrane-Cloaked Fe3O4 Nanocubes for Homologous Targeting Improvement

Surface modification of nanoparticles with cellular protein components is a new biomimetic modification strategy, which utilizes the inherent affinity between homologous cells to introduce the same surface molecules into nanoparticles to improve the targeting performance. In this study, oleic acid (OA)-coated Fe₃O₄ nanocubes were prepared by a high-temperature thermal decomposition method and modified by 3, 4-dihydroxyphenylpropionic acid (DHCA); then, HeLa cell membranes were introduced onto the surface of the nanocubes through mixed coextrusion to try to endow them with the targeting function of natural cells. The results show that the prepared Fe₃O₄ nanocubes have high monodispersity, excellent water solubility, and biocompatibility. Moreover, the Fe₃O₄ nanocubes encapsulated by cellular protein show an obvious core-shell structure and the specific targeting property to HeLa cells is improved significantly, which is expected to be used in clinical targeted diagnosis and treatment of cancer.

Hierarchical drug release designed Au @PDA-PEG-MTX NPs for targeted delivery to breast cancer with combined photothermal-chemotherapy

Breast cancer (BC) is the most frequently diagnosed cancer with a low survival rate and one of the major causes of cancer-related death. Methotrexate (MTX) is an anti-tumor drug used in the treatment of BC. Poor dispersion in water and toxic side effects limit its clinical application. Gold nanoparticles (AuNPs), owing to their specific structures and unique biological and physiochemical properties, have emerged as potential vehicles for tumor targeting, bioimaging and cancer therapy. An innovative nano drug-loading system (Au @PDA-PEG-MTX NPs) was prepared for targeted treatment of BC. Au @PDA-PEG-MTX NPs under near infra-red region (NIR) irradiation showed effective photothermal therapy against MDA-MB-231 human BC cells growth in vitro by inducing apoptosis through triggering reactive oxygen species (ROS) overproduction and generating excessive heat. In vivo studies revealed deep penetration ability of Au @PDA-PEG-MTX NPs under NIR irradiation to find application in cancer-targeted fluorescence imaging, and exhibited effective photothermal therapy against BC xenograft growth by inducing apoptosis. Histopathological analysis, cellular uptake, cytotoxicity assay, and apoptosis experiments indicated that Au @PDA-PEG-MTX NPs possessed a good therapeutic effect with high biocompatibility and fewer side effects. This Au NPs drug-loading system achieved specific targeting of MTX to BC cells by surface functionalisation, fluorescence imaging under laser irradiation, combined photothermal-chemotherapy, and pH- and NIR- triggered hierarchical drug release.

Supramolecular-interaction-mediated aggregation of anticarcinogens on triformyl cholic acid-functionalized Fe3O4 nanoparticles and their dual-targeting treatment for liver cancer

Herein, triformyl cholic acid-modified Fe₃O₄ nanoparticles (TCA-MNPs) were first constructed and developed as a novel drug carrier, possessing a high loading capacity, and the synergistic targeted therapy of hepatoma cells in vitro and in vivo.

Immobilization of protein on Fe3O4 nanoparticles for magnetic hyperthermia application

We report a facile approach for the preparation of protein conjugated glutaric acid functionalized Fe₃O₄ magnetic nanoparticles (Pro-Glu-MNPs), having improved colloidal stability and heating efficacy. The Pro-Glu-MNPs were prepared by covalent conjugation of BSA protein onto the surface of glutaric acid functionalized Fe₃O₄ magnetic nanoparticles (Glu-MNPs) obtained through thermal decomposition. XRD and TEM analyses confirmed the formation of crystalline Fe₃O₄ nanoparticles of average size ~5 nm, whereas the conjugation of BSA protein to them was evident from XPS, FTIR, TGA, DLS and zeta-potential measurements. These Pro-Glu-MNPs showed good colloidal stability in different media (water, phosphate buffer saline, cell culture medium) and exhibited room temperature superparamagnetism with good magnetic field responsivity towards the external magnet. The induction heating studies revealed that the heating efficacy of these Pro-Glu-MNPs was strongly reliant on the particle concentration and their stabilizing media. In addition, they showed enhanced heating efficacy over Glu-MNPs as surface passivation by protein offers colloidal stability to them as well as prevents their aggregation under AC magnetic field. Further, Pro-Glu-MNPs are biocompatible towards normal cells and showed substantial cellular internalization in cancerous cells, suggesting their potential application in hyperthermia therapy.