Stabilized magnetic cerasomes for drug delivery

Adsorption of Organic Dyes on Magnetic Iron Oxide Nanoparticles. Part II: Field-Induced Nanoparticle Agglomeration and Magnetic Separation

This paper (part II) is devoted to the effect of molecular adsorption on the surface of magnetic iron oxide nanoparticles (IONP) on the enhancement of their (secondary) field-induced agglomeration and magnetic separation. Experimentally, we use Methylene Blue (MB) cationic dye adsorption on citrate-coated maghemite nanoparticles to provoke primary agglomeration of IONP in the absence of the field. The secondary agglomeration is manifested through the appearance of needlelike micron-sized agglomerates in the presence of an applied magnetic field. With the increasing amount of adsorbed MB molecules, the size of the field-induced agglomerates increases and the magnetic separation on a magnetized micropillar becomes more efficient. These effects are mainly governed by the ratio of magnetic-to-thermal energy α, suspension supersaturation Δ₀, and Brownian diffusivity D_eff of primary agglomerates. The three parameters (α, Δ₀, and D_eff) are implicitly related to the surface coverage θ of IONP by MB molecules through the hydrodynamic size of primary agglomerates exponentially increasing with θ. Experiments and developed theoretical models allow quantitative evaluation of the θ effect on the efficiency of the secondary agglomeration and magnetic separation.

Raman spectroscopy to unravel the magnetic properties of iron oxide nanocrystals for bio-related applications

Iron oxide nanocrystals have become a versatile tool in biomedicine because of their low cytotoxicity while offering a wide range of tuneable magnetic properties that may be implemented in magnetic separation, drug and heat delivery and bioimaging. These capabilities rely on the unique magnetic features obtained when combining different iron oxide phases, so that an important portfolio of magnetic properties can be attained by the rational design of multicomponent nanocrystals. In this context, Raman spectroscopy is an invaluable and fast-performance tool to gain insight into the different phases forming part of the nanocrystals to be used, allowing correlation of the magnetic properties with the envisaged bio-related applications.

A perspective on magnetic core-shell carriers for responsive and targeted drug delivery systems

Magnetic core-shell nanocarriers have been attracting growing interest owing to their physicochemical and structural properties. The main principles of magnetic nanoparticles (MNPs) are localized treatment and stability under the effect of external magnetic fields. Furthermore, these MNPs can be coated or functionalized to gain a responsive property to a specific trigger, such as pH, heat, or even enzymes. Current investigations have been focused on the employment of this concept in cancer therapies. The evaluation of magnetic core-shell materials includes their magnetization properties, toxicity, and efficacy in drug uptake and release. This review discusses some categories of magnetic core-shell drug carriers based on Fe2O3 and Fe3O4 as the core, and different shells such as poly(lactic-co-glycolic acid), poly(vinylpyrrolidone), chitosan, silica, calcium silicate, metal, and lipids. In addition, the review addresses their recent potential applications for cancer treatment.

Development of Zwitterionic Polypeptide Nanoformulation with High Doxorubicin Loading Content for Targeted Drug Delivery

Much attention has been drawn to targeted nanodrug delivery systems due to their high therapeutic efficacy in cancer treatment. In this work, doxorubicin (DOX) was incorporated into a zwitterionic arginyl-glycyl-aspartic acid (RGD)-conjugated polypeptide by an emulsion solvent evaporation technique with high drug loading content (45%) and high drug loading efficiency (95%). This zwitterionic nanoformulation showed excellent colloidal stability at high dilution and in serum. The pH-induced disintegration and enzyme-induced degradation of the nanoformulation were confirmed by dynamic light scattering and gel permeation chromatography. Efficient internalization of DOX in the cells and high antitumor activity in vitro was observed. Compared with the free drug, this nanoformulation showed higher accumulation in tumor and lower systemic toxicity in vivo. The DOX-loaded zwitterionic RGD-conjugated polypeptide vesicles show potential application for targeted drug delivery in the clinic.

Advancing the Pharmaceutical Potential of Bioinorganic Hybrid Lipid-Based Assemblies

Bioinspired lipid assemblies that mimic the elaborate architecture of natural membranes have fascinated researchers for a long time. These lipid assemblies have gone from being just an imperative platform for biophysical research to a pharmaceutical delivery system for biomedical applications. Despite success, these organized nanosystems are often subject to the mechanical instability and limited theranostic capability without adding any inconvenient modifications. To reach their advanced pharmaceutical potential, various bioinorganic hybrid lipid-based assembles, which provide new opportunities to synergistically complement and improve therapeutic/diagnostic potential of existing lipid-based nanomedicine with distinct mechanisms containing inorganic embedded surfactants, have recently been developed.

Dual-targeting liposomes for enhanced anticancer effect in somatostatin receptor II-positive tumor model

Aim: We developed octreotide-modified magnetic liposomes (OMlips) as dual-targeting drug carriers to enhance the drug accumulation in tumor site. Materials & methods: Octreotide acts as a modified ligand for receptor-mediated targeting and the coated Fe3O4 nanoparticles offer the magnetic targeting property. SSTR2 overexpressed A549 cells and S180 cells were chosen to explore the targeting ability and antitumor effect of the oleanolic acid (OA)-loaded OMlips in vitro and in vivo. Results: The OMlips platform significantly improves the targeting, penetrating and accumulation of OA at the SSTR2 overexpressed cells and SSTR2-positive tumor-bearing mice. Conclusion: The OA-loaded OMlips have better antitumor effect and lower systemic toxicity. Such a receptor-mediated and magnetically-orienting dual-targeting drug nanocarriers may have great potentials in clinical practice.

Synthesis, structural and in-vitro characterization of β-cyclodextrin grafted L-phenylalanine functionalized graphene oxide nanocomposite: A versatile nanocarrier for pH-sensitive doxorubicin delivery

To enhance graphene stability, drug loading capacity and biocompatibility, β-cyclodextrin (β-CD) was grafted onto graphene oxide (GO) using L-plenylalanine (Phe) as a linker. The doxorubicin (DOX) loading efficiency and capacity of GO-Phe-CD were 78.7% and 85.2%, respectively. The cone shaped cavity of CD acts as a host for DOX loading through inclusion complex formation. The GO-Phe-CD nanocarrier showed higher release ratio of DOX in acidic milieu of cancer cells. In addition, general cytotoxicity of the nanocarriers was examined by MTT assay and trypan blue dye exclusion in MCF-7 cell lines. It was established that the MTT assay was not an appropriate technique for predicting the cytotoxicity of graphene based nanocarriers due to the spontaneous formation of MTT formazan by these materials; leading to a false high biocompatibility. According to the trypan blue experiment, the GO-Phe-CD had significant cytocompatibility, and the DOX-loaded GO-Phe-CD had outstanding killing capability to MCF-7 cells.

Folate-molecular encapsulator-tethered biocompatible polymer grafted with magnetic nanoparticles for augmented drug delivery

Magnetic ferrite nanoparticles (MNPs) coated with biocompatible polymers capable of drug loading and release are fascinating nanostructures for delivering anti-cancer drugs. Herein, we report the synthesis and characterization of a novel β-cyclodextrin-folate-tethered dextran polymer. Nickel-zinc ferrite nanoparticles are prepared and coated with the polymer to form a biocompatible hybrid magnetic nanocarrier. To establish the significance of folate unit of the polymer in anticancer activity, a similar derivatized polymer, i.e. β-cyclodextrin-dextran conjugate without folate tether is used for comparison. The size of the hybrid MNPs is ∼20 nm, which is a size suitable for cancer drug targeting. The polymer-coated magnetic nanocarriers are soft ferromagnets as suggested by their narrow magnetic hysteresis loops. The anticancer drug camptothecin (CPT) is loaded on the magnetic nanocarriers. The drug loading efficiency is observed to be above 92%. The nanocarriers show sustained in vitro drug release for above 45 h. The in vitro cytotoxicity studies reveal that the loaded CPT retains its potency in the nanocarrier and the folate-tethered nanocarrier shows better anticancer activity than the one which does not carry a folate unit. The magnetic nanocarrier is suitable for magnetic field-guided drug transport, enhanced drug loading and release and folate receptor-mediated endocytotic uptake of drugs by cancer cells.

Cerasomes and Bicelles: Hybrid Bilayered Nanostructures With Silica-Like Surface in Cancer Theranostics

Over years, theranostic nanoplatforms have provided a new avenue for the diagnosis and treatment of various cancer types. To this end, a myriad of nanocarriers such as polymeric micelles, liposomes, and inorganic nanoparticles (NPs) with distinct physiochemical and biological properties are routinely investigated for preclinical and clinical studies. So far, liposomes have received great attention for various biomedical applications, however, it still suffers from insufficient morphological stability. On the other hand, inorganic NPs depicting excellent therapeutic ability have failed to address biocompatibility issues. This has raised a serious concern about the clinical approval of multifunctional organic or inorganic-based theranostic agents. Recently, partially silica coated nanohybrids such as cerasomes and bicelles demonstrating both diagnostic and therapeutic ability in a single system, have drawn profound attention as a fascinating novel drug delivery system. Compared with traditional liposomal or inorganic-based nanoformulations, this new and highly stable nanocarriers integrates the functional attributes of biomimetic liposomes and silica NPs, therefore, synergize strengths and functions, or even surpass weaknesses of individual components. This review at its best enlightens the emerging concept of such partially silica coated nanohybrids, fabrication strategies, and theranostic opportunities to combat cancer and related diseases.

Localized delivery of curcumin into brain with polysorbate 80-modified cerasomes by ultrasound-targeted microbubble destruction for improved Parkinson's disease therapy

Rationale: Treatment for Parkinson's disease (PD) is challenged by the presence of the blood-brain barrier (BBB) that significantly limits the effective drug concentration in a patient's brain for therapeutic response throughout various stages of PD. Curcumin holds the potential for α-synuclein clearance to treat PD; however, its applications are still limited due to its low bioavailability and poor permeability through the BBB in a free form.

Methods: Herein, this paper fabricated curcumin-loaded polysorbate 80-modified cerasome (CPC) nanoparticles (NPs) with a mean diameter of ~110 nm for enhancing the localized curcumin delivery into the targeted brain nuclei via effective BBB opening in combination with ultrasound-targeted microbubble destruction (UTMD).

Results: The liposomal nanohybrid cerasome exhibited superior stability towards PS 80 surfactant solubilization and longer circulation lifetime (t_1/2 = 6.22 h), much longer than free curcumin (t_1/2 = 0.76 h). The permeation was found to be 1.7-fold higher than that of CPC treatment only at 6 h after the systemic administration of CPC NPs. Notably, motor behaviors, dopamine (DA) level and tyrosine hydroxylase (TH) expression all returned to normal, thanks to α-synuclein (AS) removal mediated by efficient curcumin delivery to the striatum. Most importantly, the animal experiment demonstrated that the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice had notably improved behavior disorder and dopamine depletion during two-week post-observation after treatment with CPC NPs (15 mg curcumin/kg) coupled with UTMD.

Conclusion: This novel CPC-UTMD formulation approach could be an effective, safe and amenable choice with higher therapeutic relevance and fewer unwanted complications than conventional chemotherapeutics delivery systems for PD treatment in the near future.

Elegant pH-Responsive Nanovehicle for Drug Delivery Based on Triazine Dendrimer Modified Magnetic Nanoparticles

Owing to properties of magnetic nanoparticles and elegant three-dimensional macromolecule architectural features, dendrimeric structures have been investigated as nanoscale drug delivery systems. In this work, a novel magnetic nanocarrier, generation two (G2) triazine dendrimer modified Fe₃O₄@SiO₂ magnetic nanoparticles (MNP-G2), was designed, fabricated, and characterized by Fourier transform infrared (FT-IR), thermal gravimetric analysis (TGA), vibrating sample magnetometer (VSM), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and dynamic light scattering (DLS). The prepared MNP-G2 nanosystem offers a new formulation that combines the unique properties of MNPs and triazine dendrimer as a biocompatible material for biomedical applications. To demonstrate the potential of MNP-G2, the nanoparticles were loaded with methotrexate (MTX), a proven chemotherapy drug. The MTX-loaded MNP-G2 (MNP-G2/MTX) exhibited a high drug-loading capacity of MTX and the excellent ability for controlled drug release. The cytotoxicity of MNP-G2/MTX using an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide based assay and MCF-7, HeLa, and Caov-4 cell lines revealed that MNP-G2/MTX was more active against the tumor cells than the free drug in a mildly acidic environment. The results of hemolysis, hemagglutination, and coagulation assays confirmed the good blood safety of MNP-G2/MTX. Moreover, the cell uptake and intracellular distribution of MNP-G2/MTX were studied by flow cytometry analysis and confocal laser scanning microscopy (CLSM). This research suggests that MNP-G2/MTX with good biocompatibility and degradability can be selected as an ideal and effective drug carrier in targeted biomedicine studies especially anticancer applications.

Near-infrared light-activatable polymeric nanoformulations for combined therapy and imaging of cancer

Near infrared (NIR) light allows deep tissue penetration and high spatial resolution due to the reduced scattering of long-wavelength photons. NIR light-activatable polymer nanoparticles are widely exploited for enhanced cancer imaging (diagnosis) and therapy owing to their superior photostability, photothermal conversion efficiency (or high emission rate), and minimal toxicity to cells and tissues. This review surveys the most recent advances in the synthesis of different NIR-absorbing and emissive polymer nanoformulations, and their applications for cancer imaging, photothermal therapy, theranostics and combination therapy by delivering multiple small molecule chemotherapeutics. Photo-responsive drug delivery systems for NIR light-triggered drug release are also discussed with particular emphasis on their molecular designs and formulations as well as photo-reaction mechanisms. Finally, outlook and challenges are presented regarding potential clinical applications of NIR light-activatable nanoformulations.

Hyaluronic Acid Conjugated Magnetic Prussian Blue@Quantum Dot Nanoparticles for Cancer Theranostics

A multifunctional nanotheranostic agent was developed by conjugating both hyaluronic acid and bovine serum albumin coated CuInS₂-ZnS quantum dots onto the surface of magnetic Prussian blue nanoparticles. The obtained nanoagent could serve as an efficient contrast agent to simultaneously enhance near infrared (NIR) fluorescence and magnetic resonance (MR) imaging greatly. The coexistence of magnetic core and CD44 ligand hyaluronic acid was found to largely improve the specific uptake of the nanoagent by CD44 overexpressed HeLa cells upon applying an external magnetic field. Both NIR fluorescence and MR imaging in vivo proved high accumulation of the nanoagent at tumor site due to its excellent CD44 receptor/magnetic dual targeting capability. After intravenous injection of the nanoagent and treatment of external magnetic field, the tumor in nude mice was efficiently ablated upon NIR laser irradiation and the tumor growth inhibition was more than 89.95%. Such nanotheranostic agent is of crucial importance for accurately identifying the size and location of the tumor before therapy, monitoring the photothermal treatment procedure in real-time during therapy, assessing the effectiveness after therapy.

Cryptotanshinone-Loaded Cerasomes Formulation: In Vitro Drug Release, in Vivo Pharmacokinetics, and in Vivo Efficacy for Topical Therapy of Acne

Cerasomes (CS), evolved from liposomes, are novel drug-delivery systems that have potential medical application as carriers for drugs or active ingredients. Although many studies have been conducted on the pharmaceutical and physicochemical properties of CS, the role of CS in influencing the in vivo plasma and topical pharmacokinetics and efficacy of topical drug delivery remain unclear. In this context, we chose cryptotanshinone (CTS) as a model drug for the preparation of CTS-CS by means of the ethanol injection method to investigate their in vitro/in vivo drug-release behavior and in vivo efficacy. (1) In in vitro studies, CTS-CS gel was proven to be capable of achieving a higher permeation rate and significant accumulation in the dermis of isolated rat skin using Franz diffusion cells. (2) In in vivo studies, microdialysis experiments used to measure the plasma and topical pharmacokinetics demonstrated that the CS had a high drug concentration, short peak time, and slow elimination. Meanwhile, the plasma area under the concentration-time curve of CTS-CS gel was less than half that for the CTS gel in 12 h, which indicates that the drug bioavailability dramatically increased in the experiments. (3) In in vivo efficacy studies, we duplicated a rat acne model and performed antiacne efficacy experiments. The CTS-CS gel improved the antiacne efficacy compared to that of ordinary CTS gel. Moreover, it inhibited the expression of interleukin-1α and androgen receptors effectively. All of these results show that CTS-CS gel has significant potential for the treatment of acne induced by inflammation and excessive secretion of androgen, suggesting that CS formulations were designed as a good therapeutic option for skin disease.

A biocompatible cerasome based platform for direct electrochemistry of cholesterol oxidase and cholesterol sensing

An electrochemical platform composed of a biocompatible cerasome and cholesterol oxidase for cholesterol sensing.

Functional magnetic Prussian blue nanoparticles for enhanced gene transfection and photothermal ablation of tumor cells

Functional magnetic Prussian blue nanoparticles as a gene carrier and photothermal agent for multi-modal cancer treatment under magnetic targeting.

Construction of antibody-like nanoparticles for selective protein sequestration in living cells

We demonstrate the successful construction of fluorescently labeled magnetic antibody-like nanoparticles (ANPs) via a facile one-step surface-initiated in situ molecular imprinting approach over silica coated magnetite (Fe3O4@SiO2) core-shell nanocomposites. The as-prepared ANPs had a highly compact structure with an overall size of 83 ± 5 nm in diameter and showed excellent aqueous dispersion stability. With the predetermined high specificity to the target protein and high biocompatibility, the ANPs enabled rapid, efficient, selective and optically trackable sequestration of target proteins within living cells. This work represents the first example of fully artificially engineered multifunctional ANPs for the intracellular protein-sequestration without disruption of the cells. The established approach may be further extended to generate ANPs for various proteins of interest and provide useful tools for related biological research and biomedical applications.

Magnetic Prussian blue nanoparticles for combined enzyme-responsive drug release and photothermal therapy

Multifunctional magnetic nanoparticles based on Fe₃O₄ nanocore and Prussian blue nanoshell for combined enzyme-responsive drug release and photothermal therapy.

β-Cyclodextrin modified graphene oxide–magnetic nanocomposite for targeted delivery and pH-sensitive release of stereoisomeric anti-cancer drugs

β-Cyclodextrin modified graphene oxide–magnetic (MGC) nanocomposite as an innovative drug carrier was the first to be developed via an effective layer-by-layer-assembly method.

Liposome supported metal oxide nanoparticles: interaction mechanism, light controlled content release, and intracellular delivery

Zwitterionic phosphotydylcholine lipo-somes stably adsorb a number of metal oxide nanoparticles via its phosphate group. This is different from physisorption and fusion with SiO2. The hybrid materials can be internalized by cancer cells and TiO2 allows light controlled liposome content release.

Efficient reduction and pH co-triggered DOX-loaded magnetic nanogel carrier using disulfide crosslinking

To reduce leakage on the drug-delivery pathway to minimize side effect of reduction or pH sensitive drug delivery systems, we designed a glutathione (GSH)/pH co-triggered magnetic nanogel drug delivery system for doxorubicin (DOX) based on the GSH concentration and pH difference between intracellular and extracellular environments. The introduction of superparamagnetic iron oxide nanoparticles (SPION) was intended for magnetic targeting. The magnetic DOX-loaded nanogel was then prepared by the oxidation of thiolated alginate with thiolated SPION in the presence of DOX. The nanogel size can be readily regulated in a range of 120-320 nm upon preparation conditions, with a negative surface charge of around -40 mV. Saturation magnetization was estimated at 27.4 emu/g Fe by VSM. In vitro release was conducted in simulated cancerous environment conditions such as a high GSH concentration and mild acidity. As a result, the nanogel expressed, upon dual stimuli of pH 5/10 mM GSH, significantly higher accumulative release than upon single stimulus of pH 5 without GSH or pH 7.4/10 mM GSH. In vitro cytotoxicity against HeLa cells clearly illustrated that the nanogel could effectively inhibit cell growth, and the IC50 was figured out to be 2.3 μg/mL of the nanogel, while the nanogel exclusive of DOX was nontoxic. Confocal laser scanning microscopy observation, combined with the result of Prussian blue staining, indicated that DOX was efficiently internalized into HeLa cells through endocytosis, released into the cytoplasm, and then principally entered the nuclei. The quantitative examination of the iron content revealed an exponential increase in the cellular uptake and an exponential decrease in the uptake efficiency with the fed nanogel. This drug-loaded nanogel could be a promising drug carrier for effective tumor-targeted chemotherapy.

Recent advances in liposomal nanohybrid cerasomes as promising drug nanocarriers

Liposomes have been extensively investigated as possible carriers for diagnostic or therapeutic agents due to their unique properties. However, liposomes still have not attained their full potential as drug and gene delivery vehicles because of their insufficient morphological stability. Recently, a super-stable and freestanding hybrid liposomal cerasome (partially ceramic- or silica-coated liposome) has drawn much attention as a novel drug delivery system because its atomic layer of polyorganosiloxane surface imparts higher morphological stability than conventional liposomes and its liposomal bilayer structure reduces the overall rigidity and density greatly compared to silica nanoparticles. Cerasomes are more biocompatible than silica nanoparticles due to the incorporation of the liposomal architecture into cerasomes. Cerasomes combine the advantages of both liposomes and silica nanoparticles but overcome their disadvantages so cerasomes are ideal drug delivery systems. The present review will first highlights some of the key advances of the past decade in the technology of cerasome production and then review current biomedical applications of cerasomes, with a view to stimulating further research in this area of study.