Prussian Blue Nanocomposite Research Articles

Cooperative amplification of Prussian blue as a signal indicator and functionalized metal-organic framework-based electrochemical biosensor for an ultrasensitive HE4 assay

Human epididymis protein 4 (HE4), a diagnostic biomarker of ovarian cancer, is crucial for monitoring the early stage of the disease. Hence, it is highly important to develop simple, inexpensive, and user-friendly biosensors for sensitive and quantitative HE4 assays. Herein, a new sandwich-type electrochemical immunosensor based on Prussian blue (PB) as a signal indicator and functionalized metal-organic framework nanocompositesas efficient signal amplifiers was fabricated for quantitative analysis of HE4. In principle, ketjen black (KB) and AuNPs modified on TiMOF (TiMOF-KB@AuNPs) could accelerate electron transfer on the electrode surface and act as a matrix for the immobilization of antibodies via cross-linking to improve the determination sensitivity. The PB that covalently binds to labeled antibodies endows the biosensors with intense electrochemical signals. Furthermore, the concentration of HE4 could be indirectly detected by monitoring the electroactivity of PB. Benefiting from the high signal amplification ability of the PB and MOF nanocomposites, this strategy displayed a wide linear range (0.1–80 ng mL−1) and a lower detection limit (0.02 ng mL−1). Hence, this study demonstrated great promise for application in clinical ovarian cancer diagnosis and treatment, and provided a new platform for detecting other cancer biomarkers.

Colorimetric and Photothermal Dual-Modal Switching Lateral Flow Immunoassay Based on a Forced Dispersion Prussian Blue Nanocomposite for the Sensitive Detection of Prostate-Specific Antigen.

Prostate-specific antigen (PSA) is a key marker for a prostate cancer diagnosis. The low sensitivity of traditional lateral flow immunoassay (LFIA) methods makes them unsuitable for point-of-care testing. Herein, we designed a nanozyme by in situ growth of Prussian blue (PB) within the pores of dendritic mesoporous silica (DMSN). The PB was forcibly dispersed into the pores of DMSN, leading to an increase in exposed active sites. Consequently, the atom utilization is enhanced, resulting in superior peroxidase (POD)-like activity compared to that of cubic PB. Antibody-modified DMSN@PB nanozymes serve as immunological probes in an enzymatic-enhanced colorimetric and photothermal dual-signal LFIA for PSA detection. After systematic optimization, the LFIA based on DMSN@PB successfully achieves a 4-fold amplification of the colorimetric signal within 7 min through catalytic oxidation of the chromogenic substrate by POD-like activity. Moreover, DMSN@PB exhibits an excellent photothermal conversion ability under 808 nm laser irradiation. Accordingly, photothermal signals are introduced to improve the anti-interference ability and sensitivity of LFIA, exhibiting a wide linear range (1-40 ng mL-1) and a low PSA detection limit (0.202 ng mL-1), which satisfies the early detection level of prostate cancer. This research provides a more accurate and reliable visualization analysis methodology for the early diagnosis of prostate cancer.

Near-infrared light-controlled kartogenin delivery of multifunctional Prussian blue nanocomposites for cartilage defect repair.

Articular cartilage injury repair remains a challenge for clinicians and researchers. Mesenchymal stem cells (MSCs) have multiple differentiation potentials and can be induced to differentiate into the chondrogenic lineage for cartilage defect repair; however, the insufficient capacity of chondrogenic differentiation and excess reactive oxygen species (ROS)-mediated oxidative stress, which always lead to differentiation into hypertrophic chondrocytes, still need to be resolved. Accordingly, kartogenin (KGN), which can promote chondrogenic differentiation of MSCs, has shown promise in promoting infected cartilage repair. However, realizing controllable release to prolong its action time and avoid hypertrophic differentiation is critical. We herein developed a mesoporous Prussian blue nanoparticle (mPB)-based near-infrared (NIR) light-responsive controlled nanosystem. KGN was encapsulated in temperature-stimulated responsive phase change materials (PCMs), which were used as excellent gating materials (KGN-PCM@mPBs). In addition, the mPBs could efficiently scavenge ROS by their enzyme-like antioxidative activities. Our study demonstrates that the nanocomposites could efficiently promote chondrogenic differentiation and successfully inhibit the hypertrophic differentiation of MSCs. By intra-articular injection of KGN-PCM@mPBs and NIR-triggered precisely controlled release, satisfactory cartilage repair effects can be achieved in a rat chondral defect model. Thus, this constructed NIR-mediated KGN-PCM@mPB nanoplatform may represent an effective cartilage repair strategy with satisfactory biosafety in clinical applications.

Record‐High Responsivity and High Detectivity Broadband Photodetectors Based on Upconversion/Gold/Prussian‐Blue Nanocomposite

AbstractThe development of high‐quality and strongly Au conjugated upconversion nanoparticles (UCNPs) is time‐consuming and requires specific chemicals. Therefore, a one‐pot hydrothermal method is adopted for novel in situ preparation of UCNP@Au composites using a binary functional ethylenediaminetetraacetic salt, which is employed as a surfactant and reducing agent. The composites are electrostatically conjugated with metal‐coordinated Prussian blue (PB) to yield UCNP@Au+PB nanocomposites (NCs), which demonstrate 21‐fold upconversion emission quenching by fluorescence resonance energy transfer compared to UCNPs. Additionally, the PB, UCNP@Au, and NCs demonstrate a synergistically reduced trap (α ≈ 0.85) and enhance ultrasensitive broadband (432–980 nm) photodetection. The NCs‐based gate‐free epitaxial graphene device demonstrates excellent high photoresponsivity (5.9 × 105 A W–1), detectivity (2.17 × 1014 ), and normalized gain (2.06 × 10−4 m2 V–1) at 318 nW cm–2 (532 nm) and a bias voltage of 1 V. The Au plasmons enhance the one‐photon‐enabled visible absorption of Er3+ ions, and PB exhibits broad absorption and enhances the carrier density of the device, resulting in an ultrahigh photoresponse. The obtained device performance is the highest to date among their class of nanohybrids. Also, these NCs can readily detect polychromatic light and signals from daily‐use appliances, indicating their potential for applications in consumer electronics.

Enzyme-catalyzed deposition of polydopamine for amplifying the signal inhibition to a novel Prussian blue-nanocomposite and ultrasensitive electrochemical immunosensing

The uncontrollable synthesis of Prussian blue (PB) and its weak stability toward OH– are great challenges affecting its electrochemical biosensing application. Herein we utilize the unique properties of chitosan (CS) to realize the facile and controllable synthesis of a CS-PB nanocomposite and combine it with the urease-catalyzed deposition of polydopamine (PDA) for amplifying the electrochemical signal inhibition of PB to develop a novel immunosensing method for protein detection. The immunosensor was constructed on a CS-PB modified electrode, and a urease-functionalized silica nanoprobe was prepared for tracing its sandwich immunoassay toward the model analyte of carcinoembryonic antigen. Besides the electrochemical impedance effect of the quantitatively captured nanoprobes, their enzymatic reaction can release numerous OH– to destroy the PB crystals and also induce the PDA deposition onto the immunosensor. These caused drastic electrochemical signal inhibition to PB. Based on the above multi-signal amplification mechanism, the method exhibits a very low detection limit of 0.042 pg mL–1 along with a very wide linear range of six-order of magnitude. In addition, the CS-PB based immunosensor has excellent specificity, repeatability, stability and reliability. Thus this PB nanocomposite and the proposed electrochemical immunosensing method reveal a promising potential for future applications.

Near-Infrared Radiation-Assisted Drug Delivery Nanoplatform to Realize Blood-Brain Barrier Crossing and Protection for Parkinsonian Therapy.

Mitochondrial dysfunction, which is directly involved in Parkinson's disease (PD), is characterized by the production of reactive oxygen species (ROS) and aberrant energy metabolism. Thus, regulating mitochondrial function might be an effective strategy to treat PD. However, the blood-brain barrier (BBB) presents a significant challenge for the intracerebral delivery of drugs. Here, we synthesized a zeolitic imidazolate framework 8-coated Prussian blue nanocomposite (ZIF-8@PB), which was encapsulated with quercetin (QCT), a natural antioxidant, to treat PD. ZIF-8@PB-QCT exhibited superior near-infrared radiation (NIR) response and penetrated through the BBB to the site of mitochondrial damage guided by the photothermal effect. In the mice model of PD, the QCT released from ZIF-8@PB-QCT significantly increased the adenosine triphosphate levels, reduced the oxidative stress levels, and reversed dopaminergic neuronal damage as well as PD-related behavioral deficits without any damage to the normal tissues. Furthermore, we explored the underlying neuroprotective mechanism of ZIF-8@PB-QCT that was mediated by activating the PI3K/Akt signaling pathway. Thus, combined with noninvasive NIR radiation, the biocompatible ZIF-8@PB-QCT nanocomposite could be used to treat neurodegenerative diseases.

Stable Solid-State Microfabricated Potentiometric Sensor Based on Chitosan- Prussian Blue Nanocomposite Film for Amlodipine Selective Detection

Solid state ion-selective electrodes have a grown importance in advanced detection techniques especially with exploiting different solid contact transducing substances. Nowadays, various approaches focus on producing simple, sensitive, durable and significantly stable electrodes. Lower cost of production could be achieved by employing simple, economical and efficient materials in their fabrication. Herein, a solid state microfabricated copper electrode was firstly designed from a reasonably priced and easily fabricated copper printed circuit boards followed by applying chitosan-Prussian blue nanocomposite layer. Finally, amlodipine sensing membrane was added resulting in construction of an amlodipine sensing microfabricated solid-state electrode. The designed electrode was characterized by being miniaturized, durable, portable, easily fabricated, affordable and highly stable over 60 d with a potential drift value of 600 μV h−1. The microfabricated electrode revealed promising results upon the direct analysis of amlodipine besylate and the responses showed a good linear Nernstian pattern in the dynamic range of 1.0 ×10−5.5 to 1.0 ×10−3 mol l−1 with a slope of 55.1 mV/decade. The detection limit was found to be 2.0 ×10−6 mol l−1. Selective determination of the drug was successfully achieved in presence of its degradation product without any sample preparation steps.

Broad-spectrum electrochemical immunosensor based on one-step electrodeposition of AuNP-Abs and Prussian blue nanocomposite for organophosphorus pesticide detection.

Broad-spectrum antibodies can effectively recognize substances with similar structures and have broad application prospects in field rapid detection. In this study, broad-spectrum antibodies (Abs) against organophosphorus pesticides (OPs) were used as sensitive recognition elements, which could effectively recognize most OPs. Gold nanoparticles (AuNPs) have good biocompatibility. It combined with Abs to form a gold-labeled probe (AuNPs-Abs), which enhances the effective binding of antibodies to nanomaterials. Prussian blue (PB) was added to electrodeposition solution to enhance the conductivity, resulting in superior electrochemical performance. The AuNP-Abs-PB composite film was prepared by electrodeposition on the electrode surface to improve the anti-interference ability and stability of the immunosensor. Under the optimal experimental conditions, the immunosensor had a wide detection range (IC20-IC80: 1.82 × 10-3-3.29 × 104ng/mL) and high sensitivity. Most importantly, it was simple to be prepared and could be used to detect multiple OPs.

Amperometric detection of glucose and H2O2 using peroxide selective electrode based on carboxymethylcellulose/polypyrrole and Prussian Blue nanocomposite

Carboxymethylcellulose (CMC), which is obtained from one of the most abundant biomass materials in the world, could have a major role in many practical applications thanks to its promising properties. In this work, electrochemical synthesis of polypyrrole (PPy) with simultaneous incorporation of CMC as dopant/plasticizing agent and Prussian Blue nanoparticles (PBNPs) as a peroxidase mimetic catalyst have been performed to design biocompatible sensor platform. CMC displays an effective mission in every stage of sensor platform formation. It increases the dispersibility of pyrrole (Py) in water with its template effect, and it enhances the conductivity of polypyrrole chains after electropolymerization by acting as a dopant and a plasticizer. Moreover, CMC in the composite structure increases the hydrophilicity of the sensor platform that may cause a significant improvement in the operational stability of the sensor. Such a 3D interwoven structure produced on the indium tin oxide electrode by a smart combination of materials used exhibited high-performance sensor responses to hydrogen peroxide (H2O2) and glucose. Sensor optimization resulted in a limit of detection (LOD) of 0.59 μM, a linear range from 5 to 470 μM and a sensitivity of 456.8 μA mM−1 cm-2 for H2O2 detection. When the same sensor platform used in glucose detection after GOx immobilization resulted in 5.23 μM LOD with a linear range from 20 and 1100 μM and a sensitivity of 456.8 μA mM−1 cm-2. Moreover, the interference of the most common interfering compounds would exist in real samples was also featured to set the ground for further sensor studies based on CMC, PPy, and PBNPs.

Sunlight assisted degradation of toxic phenols by zinc oxide doped prussian blue nanocomposite

Abstract Aromatic phenols, found in various industrial effluents, are categorized as priority pollutants and seeking attention owing to their life threatening effects. In present study, nanocomposite of zinc oxide coupled with prussian blue (ZnO@FeHCF) was synthesized by green method using Azadirachta indica leaf extract. Nanocomposite was characterized by relevant techniques and found crystalline as well as nanosized. Fabricated nanocomposite was employed for the eradication of various phenols under Sunlight. Photocatalytic degradation of phenol, 3-aminophenol (3-AP) and 2,4-dinitrophenol (2,4-DNP) was performed at different parameters of pollutant-concentration, catalyst-amount, pH, contact-time and exposure of Sunlight. Obtained results showed the maximum removal of 3-AP (97%) followed by phenol (95%) and 2,4-DNP (93%) that is attributed to their basicity differences. Compared to ZnO and FeHCF, the nanocomposite was found more effective in degrading the phenols and lowered the t1/2 value of 3-AP (4.04 h), phenol (4.405 h) and 2,4-DNP (4.68 h) to a greater-extent. Effect of different foreign-anions was also studied to verify nanocomposite’s efficiency under natural conditions. Better photocatalytic activity of the nanocomposite as compared to ZnO and FeHCF might be due to longer-life-span of charge-carriers as revealed by photoluminescence study. Mechanism of the photocatalysis was investigated by using radical-scavenger to understand the steps involved in removal process. It was found that OH was the main species promoting the degradation of phenols. Sunlight active nanocomposite found to show excellent catalytic reusability up to 10 cycles. Overall, green synthesized nanocomposite is cheap, reusable, high-surface-activity, low band gap with charge separation recommended for bright future of environment.

Efficient detection of ascorbic acid utilizing molybdenum Oxide@Prussian Blue/Graphite felt composite electrodes

A low cost, sensitive and efficient ascorbic acid (AA) sensor was developed using a molybdenum oxide (MoOx) and Prussian Blue (PB) nanocomposite, anchored on a graphite felt (GF) substrate (MoOx@PB/GF). MoO2 nanorods, which were fabricated by annealing of Mo-precursor, play a key role in promoting the synthesis of PB from Fe3+ and [Fe(CN)6]3-. The as-prepared electrode was characterized by scanning electronmicroscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and electrochemical methods. The modified electrode exhibited outstanding performances for the electrocatalytic oxidation of AA, with a sensitivity as high as 0.37 A/M, a good linear response in a concentration range from 0.0125 μM to 293 μM, an ultra-low detection limit of 0.0119 μM (S/N = 3), as well as a notable reproducibility and an excellent selectivity. Finally, the composite electrode gave satisfactory results for practical sample analyses, e.g. standard AA added in drinking water.

Activation of peroxymonosulfate by magnetic carbon supported Prussian blue nanocomposite for the degradation of organic contaminants with singlet oxygen and superoxide radicals

In order to develop efficient and green catalyst for organic pollutants removal, magnetic carbon supported Prussian blue nanocomposite Fe3O4@C/PB was prepared for the first time. The performance of Fe3O4@C/PB in activating peroxymonosulfate (PMS) for the degradation of 2,4-dichlorophenol (2,4-DCP) was investigated. 2,4-DCP could be effectively degraded under the “Fe3O4@C/PB + PMS” system within a broad pH range of 2–9. Without pH adjustment (pH 3), 2,4-DCP (20 mg/L) was completely degraded in 50 min along with a 70% removal of TOC; while the required time for complete degradation of 2,4-DCP was shortened to 40 min under initial solution pH at 7. Fe3O4@C/PB could also activate PMS for the degradation of phenol, Acid Orange II, Reactive brilliant red X-3B, Rhodamine B and Methylene blue. The degradation rates higher than 95% could be achieved for all these contaminants within the time scale of 15–60 min. The studies of radical-quenching and electron paramagnetic resonance demonstrated that singlet oxygen (1O2) and superoxide radicals (O2−), rather than sulfate (SO4−) and hydroxyl (OH) radicals, were the dominant species responsible for the oxidation of organic pollutants. The plausible mechanism of the catalytic degradation was proposed and the enhanced activity of Fe3O4@C/PB was assumed to be related to the increased electron transfer owing to the synergic effect between the magnetic carbon and the mixed-valence units in PB. Fe3O4@C/PB is promising in wastewater treatment owing to its high efficiency, excellent stability and reusability, environmental friendliness and magnetic separability.

In situ growth of Prussian blue nanocubes on polypyrrole nanoparticles: facile synthesis, characterization and their application as fiber optic gas sensor

Polypyrrole (PPy) and polypyrrole/Prussian blue (PPy–PB) nanocomposite-based fiber optic gas sensors are developed for gas sensing application. Prussian blue (PB) nanocubes are successfully grown on polypyrrole (PPy) nanoparticles by in situ oxidative polymerization method to obtain PPy–PB nanocomposite. PPy and PPy–PB are evaluated based on structural, morphological and electrical properties. The characteristic peaks present in the FTIR spectra of pure PPy and PB nanoparticles are also present in the FTIR spectrum of PPy–PB nanocomposite with small shifts in the absorption maximum. The XRD pattern reveals the semicrystalline structure of PPy–PB nanocomposite with an average crystallite size of 22 nm, and the morphology (FESEM) shows the formation of PB nanocubes over PPy matrix. AC conductivity measurements show slight improvement in the conductivity value of PPy–PB in comparison with PPy. Dielectric studies in the frequency range of 50 Hz–5 MHz reveal that PPy–PB nanocomposite is a high-k dielectric material. At 50 Hz, PPy–PB exhibits high dielectric constants of 1149 and 766 with low dielectric loss values of 9.9 and 4.6 at 150 and 120 °C, respectively. Further, their application as fiber optic gas sensors in sensing various gases is studied using fiber optic technique. The spectral response is studied for various concentrations (0–500 ppm) of ammonia, acetone and ethanol gases at room temperature. The study shows that the spectral intensity increases linearly with different concentrations of all gases. The clad-modified fiber optic sensor with PPy–PB nanocomposite exhibits enhanced sensitivity for ethanol than clad-modified fiber optic sensor with PPy nanoparticles. TGA studies reveal the high thermal stability of PPy–PB nanocomposite. Hence, PPy–PB-based fiber optic sensors can be used to sense toxic ethanol vapor not only at room temperature but also in a composite environment where a temperature variation is expected.

A reagent-free paper-based sensor embedded in a 3D printing device for cholinesterase activity measurement in serum

Abstract Herein, we report a first example of a rapid and easy to use paper-based printed sensor embedded in a 3D printing device to measure the butyrylcholinesterase activity in serum samples. The innovative device relies on a paper-based sensor fabricated using wax printing and screen-printing technologies, combined with a printed holder made by stereolithography using 3D printing technology. To measure the butyrylcholinesterase activity, butyrylthiocholine was used as enzymatic substrate and the by-product thiocholine was detected with a paper-based electrochemical sensor modified with a Carbon Black and Prussian Blue nanocomposite. The presence of this nanocomposite allowed to perform the butyrylcholinesterase activity measurement at low applied potential (+300 mV vs. Ag/AgCl pseudoreference), since it is able to electrocatalyse the thiocholine oxidation, overcoming the fouling problem occurring at a bare electrode. To obtain a “reagent free” sensor, butyrylthiocholine was loaded on the filter paper for a reliable stand-alone measurement, requiring only the sample addition. This device, after the calibration with standard solutions, was tested in serum samples, achieving a linear range up to 12 UI/mL and a detection limit of 0.5 IU/mL. To evaluate the accuracy of the device, recovery studies were performed in serum samples, demonstrating the suitability as a point of care for screening analysis of BChE activity measurement, taking into account that the normal value range is comprised between 5.9 and 13.2 IU/mL.

Targeted Pegylated Plga-Coated Prussian Blue Nanocomposite for Dual-Modality Pa/Mr Imaging and Synergistic Chemothermal Tumor Therapy

To prepare a PEGylated poly (lactic-co-glycolic acid) (PLGA) targeting with folic acid (FA) coated Prussian blue nanoparticles (PB NPs) and paclitaxel (PTX), to construct multifunctional PLGA-PB-PTX-PEG-FA nanocomposite for both photoacoustic (PA) imaging, magnetic resonance imaging (MRI) and synergistic chemo-thermal tumor therapy. Paclitaxel (PTX)-loaded Folic acid (FA) targeted PEGylated PLGA nanoparticles encapsulating Prussian Blue (PB) (PLGA-PB-PTX-PEG-FA) nanocomposite was fabricated by a modified double emulsion (water/oil/water) evaporation process. The morphology, size, UV–vis–NIR absorbance spectra, Fourier transfer infrared (FTIR) spectrum were tested to evaluate the structural characterization of PLGA-PB-PTX-PEG-FA. Drug Loading and releasing of PLGA-PB-PTX-PEG-FA nanocomposite were assessed by high performance liquid chromatography (HPLC). Additionally, in vitro cell targeting and in vivo tumor targeting were verified by confocal laser scanning microscopy (CLSM) and vital fluorescence imaging (VFI) to assess the targeting effect of PLGA-PB-PTX-PEG-FA nanocomposite. The efficacy of the contrast agent for PA imaging and MRI was evaluated by in vitro and in vivo imaging of subcutaneous MDA-MB-231 tumor-bearing mice following tail intravenous injection of the contrast agent. Finally, to visualize the photothermal cytotoxicity of PLGA-PB-PTX-PEG-FA nanocomposite, MDA-MB-231 cells were incubated with PLGA-PB-PTX-PEG-FA nanocomposite in 96 well-plate for 2 h and were irradiated with or without NIR laser. CCK8 method was used to measure the viability of the cells. To study the photothermal effect and synergistic therapeutic efficacy, PLGA-PB-PTX-PEG-FA nanocomposite suspensions of various concentrations nanoparticle dispersions were exposed to a laser with the wavelength of 808 nm and the output power of 0.647W/cm2 for 10min in vitro or in vivo after vein intravenous injection. The highly dispersed PLGA-PB-PTX-PEG-FA nanocomposite with spherical morphology has good uniformity with an average hydrodynamic diameter of 236.6±55.04nm. Both PB and PLGA-PB-PTX-PEG-FA nanocomposite displayed a broad absorption band with a strong absorption peak at ∼702 nm. While the IR spectrum of the PLGA-PB-PTX-PEG-FA nanocomposite showed both the corresponded peaks of PLGA- PEG-FA and PB NPs. The results of drug loading efficiency and drug loading capacity tested by HPLC were 77.82% and 7.22%. The fast drug release from the nanocomposite in vitro with laser irradiation indicated the great potential as a controlled-release system for the anticancer drug. In vitro cell targeting and in vivo tumor targeting results, targeted group had obvious difference from non-targeted group and blank control group, which showed that good targeting effect to tumor cells or tumor in vivo. After the tail intravenous injection of the PLGA-PB-PTX-PEG-FA nanocomposite, the PA images and MR images of tumor of nude mice were significantly enhanced, while there were almost no distinct enhancement in non-targeted group and blank control group. The result of the photothermal cytotoxicity of PLGA-PB-PTX-PEG-FA nanocomposite showed that the viability of the cells of PLGA-PB-PTX-PEG-FA nanocomposite+Laser group was lowest. The results of photothermal conversion property of PLGA-PB-PTX-PEG-FA suggested the character of photothermal effect was positively correlated with the heating power and the nanoparticles concentration and exhibited good photostability. Upon near-infrared laser irradiation, the PLGA-PB-PTX-PEG-FA nanocomposite showed an enhanced synergistic photothermal and chemical therapeutic efficacy for breast cancer. In conclusion, we prepared highly dispersed core-shell structure PLGA-PB-PTX-PEG-FA nanocomposite by coating PB NPs with PLGA-FA shell and then modifying with PEG. The prepared PLGA-PB-PTX-PEG-FA nanocomposite has good biocompatibility, excellent photo-thermal transformation capacity, and can enhance both PA imaging and MR imaging in vitro and in vivo. Furthermore, PLGA-PB-PTX-PEG-FA nanocomposite acts as a multifunctional drug delivery system with higher drug loading capacity and excellent drug controlled release-system. Finally, our result confirmed that PLGA-PB-PTX-PEG-FA nanocomposite has the ability of the synergistic therapeutic efficacy combined photothermal and chemical therapy effect, which further enhances the therapeutic efficacy to breast cancer.

Facile synthesis of pectin-stabilized magnetic graphene oxide Prussian blue nanocomposites for selective cesium removal from aqueous solution

This work focused on the development of pectin-stabilized magnetic graphene oxide Prussian blue (PSMGPB) nanocomposites for removal of cesium from wastewater. The PSMGPB nanocomposite showed an improved adsorption capacity of 1.609mmol/g for cesium, compared with magnetic graphene oxide Prussian blue, magnetic pectin Prussian blue, and magnetic Prussian blue nanocomposites, which exhibited adsorption capacities of 1.230, 0.901, and 0.330mmol/g, respectively. Increased adsorption capacity of PSMGPB nanocomposites was attributed to the pectin-stabilized separation of graphene oxide sheets and enhanced distribution of magnetites on the graphene oxide surface. Scanning electron microscopy images showed the effective separation of graphene oxide sheets due to the incorporation of pectin. The optimum temperature and pH for adsorption were 30°C and 7.0, respectively. A thermodynamic study indicated the spontaneous and the exothermic nature of cesium adsorption. Based on non-linear regression, the Langmuir isotherm fitted the experimental data better than the Freundlich and Tempkin models.

Magnetic Prussian Blue Nanocomposites for Effective Cesium Removal from Aqueous Solution

Magnetic Prussian blue (PB) nanocomposites were synthesized by binding PB to a core of magnetite (Fe3O4) nanoparticles for highly efficient and rapid separation of cesium (Cs+) from aqueous solution. The average particle size of the magnetic PB nanocomposites was 13.6 nm, and they had a high surface area (322.19 m2/g), leading to efficient Cs+ adsorption capability. The nanocomposites showed a maximum sorption capacity of 280.82 mg/g at an initial Cs+ concentration of 50 mM, pH 7, and 10 °C, which is much higher than those of previously reported PB-based adsorbents for removing Cs+. The adsorption behavior followed pseudo-second-order kinetics and obeyed the Tempkin isotherm. The adsorption capacity of Cs+ on magnetic PB nanocomposites remained consistent even at high ionic competition in the simulated seawater. The obtained magnetic PB nanocomposite is a cost-effective adsorbent and can be easily retrieved from an aqueous solution by a magnet after decontamination of cesium. These results showed that the...

One-Pot Hydrothermal Synthesis of Magnetite Prussian Blue Nano-Composites and Their Application to Fabricate Glucose Biosensor.

In this work, we presented a simple method to synthesize magnetite Prussian blue nano-composites (Fe3O4-PB) through one-pot hydrothermal process. Subsequently, the obtained nano-composites were used to fabricate a facile and effective glucose biosensor. The obtained nanoparticles were characterized using transmission electron microscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy, UV-vis absorbance spectroscopy, cyclic voltammetry and chronoamperometry. The resultant Fe3O4-PB nanocomposites have magnetic properties which could easily controlled by an external magnetic field and the electro-catalysis of hydrogen peroxide. Thus, a glucose biosensor based on Fe3O4-PB was successfully fabricated. The biosensor showed super-electrochemical properties toward glucose detection exhibiting fast response time within 3 to 4 s, low detection limit of 0.5 µM and wide linear range from 5 µM to 1.2 mM with sensitivity of 32 µA∙mM−1∙cm−2 and good long-term stability.

Synthesis and characterization of bimetallic noble metal nanoparticles for biomedical applications

ABSTRACTWe report herein a facile approach to synthesize processable bimetallic nanoparticles (Pd-Au/AuPd/Ag-Au/Au-Ag) decorated Prussian blue nanocomposite (PB-AgNP). The presence of cyclohexanone/formaldehyde facilitates the formation of functional bimetallic nanoparticles from 3-aminopropyltrimethoxysilane (3-APTMS) capped desired ratio of hetero noble metal ions. The use of 3-APTMS and cyclohexanone also enables the synthesis of polycrystalline Prussian blue nanoparticles (PBNPs). As synthesized PBNPs, Pd-Au/Au-Pd/Ag-Au/Au-Ag enable the formation of nano-structured composites displaying better catalytic activity than that recorded with natural enzyme. The nanomaterials have been characterized by Uv-Vis, FT-IR and Transmission Electron Microscopy (TEM) with following major findings: (1) 3-APTMS capped noble metal ions in the presence of suitable organic reducing agents i.e.; 3 glycidoxypropyltrimethoxysilane (GPTMS), cyclohexanone and formaldehyde; are converted into respective nanoparticles under ambient conditions, (2) the time course of synthesis and dispersibility of the nanoparticles are found as a function of organic reducing agents, (3) the use of formaldehyde and cyclohexanone in place of GPTMS with 3-APTMS outclasses the other two in imparting better stability of amphiphilic nanoparticles with reduced silanol content, (4) simultaneous synthesis of bimetallic nanoparticles under desired ratio of palladium/gold and silver/ gold cations are recorded, (5) the nanoparticles made from the use of 3-APTMS and cyclohexanone enable the formation of homogeneous nanocomposite with PBNP as peroxidase mimetic representing potential substitute of peroxidase enzyme. The peroxidase mimetic ability has been found to vary as a function of 3-APTMS concentration revealing the potential role of functional metal nanoparticles in bioanalytical applications.

One-pot synthesis of ternary polypyrrole⿿Prussian-blue⿿graphene-oxide hybrid composite as electrode material for high-performance supercapacitors

A ternary composite of polypyrrole (PPy), Prussian blue (PB), and graphene oxide (GO), PPy⿿PB⿿GO, was successfully prepared through spontaneous polymerization of pyrrole and formation of PB nanocubes on GO. The obtained nanocomposite was characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The results indicate that the PPy-protected PB nanocubes were well dispersed on the GO. Electrochemical testing showed a specific capacitance of 525.4Fg⿿1 at a current density of 5Ag⿿1 in the potential range from ⿿0.2 to 0.6V, obtained in an electrolyte of 1molL⿿1 KNO3 during the galvanostatic charge⿿discharge cycles, which is superior to the performance of binary cathode materials, including PPy⿿PB and PPy⿿GO nanocomposites. The as-prepared supercapacitor could retain a specific capacitance of 96% after 2000 cycles. It was confirmed that the three components⿿PPy, PB, and GO⿿led to the display of integrated electrochemical behavior and a resulting capacitor with enhanced performance. The significant enhancement in electrochemical performance of the ternary nanocomposite can be attributed to the synergistic effect of PPy-protected PB nanocubes dispersed on GO sheets with the pseudocapacitance from PB and PPy on the double-layer capacitance from GO.