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Background: Alendronate (AL), a drug for inhibiting osteoclast-mediated bone-resorption, was intercalated into an inorganic drug delivery nanovehicle, layered double hydroxide (LDH), to form a new nanohybrid, AL-LDH, with 1:1 heterostructure along the crystallographic C-axis. Based on the intercalation reaction strategy, the present AL-LDH drug delivery system (DDS) was realized with an enhanced drug efficacy of AL, which was confirmed by the improved proliferation and osteogenic differentiation of osteoblast-like cells (MG63)., Methods: The AL-LDH nanohybrid was synthesized by conventional ion-exchange reaction and characterized by powder X-ray diffraction (PXRD), high-resolution transmission electron microscopy (HR-TEM), and Fourier transform infrared (FT-IR) spectroscopy. Additionally, in vitro efficacy tests, such as cell proliferation and alkaline phosphatase (ALP) activity, were analyzed., Results: The AL was successfully intercalated into LDH via ion-exchange reaction, and thus prepared AL-LDH DDS was X-ray single phasic and chemically well defined. The accumulated AL content in MG63 cells treated with the AL-LDH DDS nanoparticles was determined to be 10.6-fold higher than that within those treated with the intact AL after incubation for 1 hour, suggesting that intercellular permeation of AL was facilitated thanks to the hybridization with drug delivery vehicle, LDH. Furthermore, both in vitro proliferation level and ALP activity of MG63 treated with the present hybrid drug, AL-LDH, were found to be much more enhanced than those treated with the intact AL. This is surely due to the fact that LDH could deliver AL drug very efficiently, although LDH itself does not show any effect on proliferation and osteogenic differentiation of MG63 cells., Conclusion: The present AL-LDH could be considered as a promising DDS for improving efficacy of AL., Competing Interests: Disclosure: The authors have no potential conflicts of interest to disclose.

The biodegradable inorganic nanovector based on a layered double hydroxide (LDH) holds great promise for gene and drug delivery systems. However, in vivo targeted delivery of genes through LDH still remains a key challenge in the development of RNA interference therapeutics. Here, we describe in vivo and in vitro delivery system for Survivin siRNA (siSurvivin) assembled with passive LDH with a particle size of 100 nm or active LDH conjugated with a cancer overexpressing receptor targeting ligand, folic acid (LDHFA), conferring them an ability to target the tumor by either EPR-based clathrin-mediated or folate receptor-mediated endocytosis. When not only transfected into KB cells but also injected into xenograft mice, LDHFA/siSurvivin induced potent gene silencing at mRNA and protein levels in vitro, and consequently achieved a 3.0-fold higher suppression of tumor volume than LDH/siSurvivin in vivo. This anti-tumor effect was attributed to a selectively 1.2-fold higher accumulation of siSurvivin in tumor tissue compared with other organs. Targeting to the tumor with inorganic nanovector can guide and accelerate an evolution of next-generation theranosis system., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A universal technology for the encapsulative protection of unstable anionic species by highly stable layered metal oxide has been developed via the surface modification of a metal oxide nanosheet. The surface anchoring of (3-aminopropyl)triethoxysilane (APTES) on exfoliated titanate nanosheet yields a novel cationic metal oxide nanosheet, which can be universally used for the hybridization with various biological and inorganic anions. The encapsulation of deoxyribonucleic acid (DNA) in the cationic APTES-anchored titanate lattice makes possible the reliable long-term protection of DNA against enzymatic, chemical, and UV-vis light corrosions. The encapsulated DNA can be easily released from the titanate lattice via sonication, underscoring the functionality of the cationic APTES-anchored titanate nanosheet as a stable nanocontainer for DNA. The APTES-anchored titanate nanosheet can be also used as an efficient CO2 adsorbent and a versatile host material for various inorganic anions like polyoxometalates, leading to the synthesis of novel intercalative nanohybrids with unexplored properties and useful functionalities.

Ordered porous carbon films with tunable pore diameters, immobilized with glucose oxidase (GOD) have been fabricated and employed for the construction of a biosensor for glucose molecules. The as-prepared porous films have large specific surface areas and highly ordered porous structure with uniform pore sizes, which are critical for the immobilization of large amounts of GOD and support the promotion of heterogeneous electron transfer. The developed biosensors give enough room for the encapsulation of a high amount of GOD molecules and show excellent biosensing performance with a linear response to glucose concentration ranging from 0.5 to 9 mM and a detection limit of 1.5 μM. It is also demonstrated that the sensitivity of the biosensor can be easily tuned by modulating the pore size of carbon film as it dictates the amount of immobilization of GOD in the porous channels. The fabricated carbon-film-based biosensor has a good stability and a high reproducibility, which opens the gateway for the commercialization of this excellent technology., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Recently, graphitic carbon nitride (g-C3N4) materials have received a great attention from many researchers due to their various roles as a visible light harvesting photocatalyst, metal-free catalyst, reactive template, nitrogen source of nitridation reaction, etc. g-C3N4 could be prepared by temperature-induced polymerization of cyanamide or melamine. In this study, we report a preparation of mesoporous graphitic carbon nitrides with tailored porous texture including pore size, and specific surface area from cyanamide and colloidal silica nanoparticles (Ludox). At first, cyanamide-silica nanocomposites were prepared by mixing colloidal silica with different size in the range of 7-22 nm and cyanamide, followed by evaporating the solvent in the resulting mixture. Mesoporous g-C3N4 samples were prepared by calcining cyanamide-silica nanocomposite at 550 degrees C for 4 hrs and removing the silica nanoparticles by using ammonium hydrogen fluoride. The formation of g-C3N4 was confirmed by the sharp (002) peak (d = 3.25 A) of graphitic interlayer stacking, and the broad (100) peak (d = 6.86 A) of in-plane repeating unit in the X-ray diffraction patterns. According to N2 adsorption-desorption analysis, the pore size of mesoporous carbon nitrides was similar to the size of colloidal silica used as hard template (7-22 nm). The specific surface area of mesoporous g-C3N4 could be tailored in the range of 189 m2/g-288 m2/g.

In this review, we are going to demonstrate the recent progresses in inorganic nanomaterial-based nanomedicines and their labeling for effective biological imaging. Nanomaterials which are classified according to their dimensionality, from zero- to three-dimensions can be utilized as nanomedicines including drug delivery, therapy and diagnosis. In the following section, the labeling of nanomaterials with various contrasting agents are introduced. Various labeling agents like fluorescence, quantum dots, upconversion nanoparticles, magnetic particles and radioisotopes can be tagged on nanomaterials for effective imaging such as optical, magnetic resonance, computed tomography, positron emission tomography and etc. The labeling of contrasting agent on nanomedicine can be summarized into intercalation, surface modification, embedment and combination depending on how and where the label is tagged. Through these approaches, multimodal biological imaging and multifunctional nanomedicine could be suggested.

Sepiocite, a synthetic sepiolite-like nanoclay, was derived from hydrotalcite-like Mg2Al(CO3)0.5-layered double hydroxide (LDH) under phase transformation at 270 +/- 3 degrees C. The crystal structure of sepiocite is conceptually very similar to that of sepiolite derived from montmorillonite clay because sepiocite is formed through the alternation of the blocks and tunnels along the crystallographic c-axis, with a partial dehydroxylation of the octahedral Mg-(OH)-Al configuration into tetrahedral ones. Three important findings regarding sepiocite were arrived at: (i) its high specific surface area of 128.25 m2/g with an average particle size of 200 nm, which is approimately equal to 3.5 times larger than the specific surface area of the pristine LDH (34.21 m2/g); (ii) its non-swelling property; and (iii) its strongly reduced anion-exchange capacity.

The exfoliation of layered Li[Mn(1/3)Co(1/3)Ni(1/3)]O(2) into individual monolayers could be achieved through the intercalation of quaternary tetramethylammonium (TMA(+)) ions into protonated metal oxide. An effective exfoliation occurred when the TMA(+)/H(+) ratio was 0.5-50. Reactions outside this range produced no colloidal suspension, but all the manganese cobalt nickel oxides precipitated. Atomic force microscopy and transmission electron microscopy clearly demonstrated that exfoliated manganese cobalt nickel oxide nanosheets have a nanometer-level thickness, underscoring the formation of unilamellar nanosheets. The maintenance of the hexagonal atomic arrangement of the manganese cobalt nickel oxide layer upon the exfoliation was confirmed by selected area electron diffraction analysis. According to diffuse reflectance ultraviolet--visible spectroscopy, the exfoliated manganese cobalt nickel oxides displayed distinct absorption peaks at approximately 354 and approximately 480 nm corresponding to the d-d transitions of octahedral metal ions, which contrasted with the featureless spectrum of the pristine metal oxide. In the light of zeta potential data showing the negative surface charge of manganese cobalt nickel oxide nanosheets, a heterolayered film of manganese cobalt nickel oxide and conductive polymers could be prepared through the successive coating process with colloidal suspension and polycations. The UV--vis and X-ray diffraction studies verified the layer-by-layer ordered structure of the obtained heterolayered film, respectively.

New porous heterostructure of TiO(2)-MoO(3) nanohybrids have been successfully synthesized via an exfoliation and reassembling method: the hybridization between TiO(2) and MoO(3) gives rise to a remarkable enhancement of the reversible capacity of 420 mAhg(-1).

We have developed a direct nonhydrothermal route to nanostructured chalcogen-doped manganese oxides; K(x)MnO(2)Q(y) (Q = S, Se, and Te). According to combinative diffraction and microscopic analyses, the S- and Se-doped manganese oxides exhibit 1D nanowire-type morphology with layered delta-MnO(2)- and alpha-MnO(2)-structures, respectively, whereas the Te-doped compound consists of 3D nanospheres that are amorphous according to X-ray diffraction. X-ray absorption and X-ray photoelectron spectroscopy analyses clearly demonstrate that the doped chalcogen ions exist in the form of hexavalent chalcogenate clusters mainly on the sample surface or grain boundary. According to electrochemical and ex situ X-ray absorption spectroscopy investigations, the Se-doped manganate nanowires show higher structural stability and better electrode performance with excellent rate characteristics compared to the S-/Te-doped and undoped manganate nanostructures. This is attributed to the presence of chemically stable SeO4(2-) species, leading to enhanced stability of the manganate lattice through the prevention of structural deformation during cycling and/or to the improvement of Li(+) ion transport through the maintenance of intercrystallite voids. Based on the present experimental findings, we are able to conclude that the present one-pot soft-chemical route with chalcogen dopants can provide a simple method not only to economically synthesize 1D nanostructured manganese oxides but also to finely control their electrode performance, crystal structure and morphology, and lattice stability.

We have tried to control the aspect ratio and physicochemical properties of 1D nanostructured manganese oxides through copper doping. Copper-doped manganese oxide nanostructures have been synthesized by one-pot hydrothermal treatment for the mixed solution of permanganate anions and copper cations. According to powder X-ray diffraction and electron microscopic analyses, all the present materials commonly crystallize with alpha-MnO2-type structure but their aspect ratio decreases significantly with increasing the content of copper. Such a variation of crystallite dimension is attributable to the limitation of crystal growth by the incorporation of copper ions. X-ray absorption spectroscopic studies at Mn K- and Cu K-edges clearly demonstrate that the average oxidation state of manganese ions is increased by the substitution of divalent copper ions. Electrochemical measurements reveal the improvement of the electrode performance of nanostructured manganate upon copper doping, which can be interpreted as a result of the decrease of aspect ratio and the increase of Mn valence state. From the present experimental findings, it becomes certain that the present Cu doping method can provide an effective way of controlling the crystal dimension and electrochemical property of 1D nanostructured manganese oxide.

Nanostructured Mn(1-x-y)Co(x)Ni(y)O2 metal oxides are synthesized by one-pot hydrothermal reaction at low temperature. From powder X-ray diffraction and field emission-scanning electron microscopic analyses, it is found that the crystal structure and crystal morphology of the present materials are tunable by the control of the composition of precursor. 1D nanowires with alpha-MnO2-type structure are prepared with low substitution rate of Co and Ni, while the increase of substituent contents leads to the formation of delta-MnO2-structured 3D nanospheres consisting of 2D nanoplates. According to X-ray absorption near edge spectroscopy and chemical analyses, mixed valent Co(III)/Co(IV) and divalent Ni(II) ions are stabilized in the octahedral Mn sites of alpha-MnO2- and delta-MnO2-structures. The electrochemical measurements clearly demonstrate that the present nanostructured materials show promising electrode performances for lithium secondary batteries.

Solid transchelation reaction was established for the synthesis of bis(N-oxopyridine-2-thionato) zinc (II), commonly known as zinc pyrithione (ZPT), to control particle size using zinc basic salt (ZBS) and aqueous sodium pyrithione solution. Distinguished from ZPT particles prepared by usual precipitation reaction, the obtained ZPT nanoparticles exhibited very narrow size distribution. X-ray absorption spectroscopy (XAS) at Zn K-edge was systematically examined to elucidate time-dependent local structural evolution during solid transchelation reaction. X-ray absorption near edge structure (XANES) analysis clearly revealed that local environment around zinc atoms transformed into pentahedron as reaction proceeded. Based on quantitative X-ray diffraction and XANES analysis, we made structural models. Theoretical XAS spectrum calculated with FEFF code could reproduce experimental one, suggesting that XAS analysis could be very powerful tool to probe phase transformation. Furthermore, according to extended X-ray absorption fine structure (EXAFS) fitting results, Zn-O distance in reaction products gradually increased from 1.96 to 2.07 angstroms, suggesting that zinc atoms bounded with oxygen ones in ZBS were transchelated with pyrithione ligands. This study could be a strong evidence for the usefulness of XAS to study time-dependent structural transformation of nanocrystalline materials.

Poly-(3,4-ethylenedioxythiophene) (PEDOT) is an ideal polymer for electrochromic (EC) devices due to its fast response time, high conductivity, and facile fabrication in a doped form except its demerit like an optical contrast limitation. In this study, we developed a simple way to overcome low coloration efficiency of PEDOT through fabricating a complementary PEDOT and prussian blue full cell system. Fundamental properties of EC displays, such as optical contrast, coloration efficiency, and switching speed, could be successfully optimized by controlling the deposition time and applied voltage during EDOT polymerization. In particular, UV transmittance spectra indicated that the optical contrast was enhanced up to 31 approximately 99% at the wavelength of 600 nm. Scanning electron microscopy images showed that the optimized PEDOT and prussian blue films were deposited on ITO glass substrate with an uniform thickness of approximately 180 nm and approximately 190 nm, respectively. Moreover, according to the circuit analysis, the average response time of electric current for the optimized full cell system was about 400 ms. It is, therefore, concluded that such a full cell system could have high potential applications as smart windows and/or optical devices.

Mesoporous silica materials were prepared through a novel mixed micelle-template method which was employed by alkyl polyethylene oxide (C16,E20) and C2-ceramide. X-ray diffraction patterns clearly showed the formation of mesoporous silica by contribution of mixed micelle-template up to 3/1 weight ratio (C16E20/C2-ceramide). TEM and N2 adsorption isotherms analyses indicated that the mesoporous structure was maintained even after encased C2-ceramides. However, when the weight ratio of C16E20/C2-ceramide exceeds 2/2, less ordered and irregular pore structure was observed. According to the in-vitro experiment on cancer cells such as MCF-7, HOS, and HepG2, the simultaneously encapsulated C2-ceramide shows apoptosis. Therefore, the present results could provide a new method for mesoporous material as drug delivery system.

We present the mechanism for the cellular uptake of layered double hydroxide (LDH) nanoparticles that are internalized into MNNG/HOS cells principally via clathrin-mediated endocytosis. The intracellular LDHs are highly colocalized with not only typical endocytic proteins, such as clathrin heavy chain, dynamin, and eps15, but also transferrin, a marker of the clathrin-mediated process, suggesting their specific internalization pathway. LDHs loaded with an anticancer drug (MTX-LDH) were also prepared to confirm the efficacy of LDHs as drug delivery systems. The cellular uptake of MTX was higher in MTX-LDH-treated cells than in MTX-treated cells, giving a lower IC50 value for MTX-LDH than for MTX only. The inhibition of the cell cycle was greater for MTX-LDH than for MTX only. This result clearly shows that the internalization of LDH nanoparticles via clathrin-mediated endocytosis may allow the efficient delivery of MTX-LDH in cells and thus enhance drug efficacy.

Zinc oxide-layered titanate nanohybrids with a 1 ratio 1 ordered heterostructure have been successfully synthesized by reassembling exfoliated titanate nanosheets in the sol solution of zinc acetate under hydrothermal conditions.

Ordered porous carbon films with tunable pore diameters, immobilized with glucose oxidase (GOD) have been fabricated and employed for the construction of a biosensor for glucose molecules. The as-prepared porous films have large specific surface areas and highly ordered porous structure with uniform pore sizes, which are critical for the immobilization of large amounts of GOD and support the promotion of heterogeneous electron transfer. The developed biosensors give enough room for the encapsulation of a high amount of GOD molecules and show excellent biosensing performance with a linear response to glucose concentration ranging from 0.5 to 9 m M and a detection limit of 1.5 μ M. It is also demonstrated that the sensitivity of the biosensor can be easily tuned by modulating the pore size of carbon film as it dictates the amount of immobilization of GOD in the porous channels. The fabricated carbon-film-based biosensor has a good stability and a high reproducibility, which opens the gateway for the commercialization of this excellent technology. [ABSTRACT FROM AUTHOR]

Poor aqueous solubility and the unpleasant taste of aripiprazole (APZ) have been recurring problems, owing to its low bioavailability and low patient tolerance, respectively. Herein, we prepared a nanohybrid system that was based on a bentonite clay material, montmorillonite (MMT), which could both mask the taste and enhance the solubility of APZ (i.e., APZ-MMT). To further improve the efficacy of this taste masking and drug solubility, APZ-MMT was also coated with a cationic polymer, polyvinylacetal diethylamino acetate (AEA). In vitro dissolution tests at neutral pH showed that the amount of drug that was released from the AEA-coated APZ-MMT was greatly suppressed (<1 %) for the first 3 min, thus suggesting that AEA-coated APZ-MMT has strong potential for the taste masking of APZ. Notably, in simulated gastric juice at pH 1.2, the total percentage of APZ that was released within the first 2 h increased up to 95 % for AEA-coated APZ-MMT. Furthermore, this in vitro release profile was also similar to that of Abilify®, a commercially available medication. In vivo experiments by using Sprague-Dawley rats were also performed to compare the pharmacokinetics of AEA-coated APZ-MMT and Abilify®. AEA-coated APZ-MMT exhibited about 20 % higher systemic exposure of APZ and its metabolite, dehydro-APZ, compared with Abilify®. Therefore, a new MMT-based nanovehicle, which is coated with a cationic polymer, can act as a promising delivery system for both taste masking and for enhancing the bioavailability of APZ. [ABSTRACT FROM AUTHOR]

We briefly address the recent challenges and strategies to 'infohybrids' that combines hybrid science and information technology. The aspects of the infohybrid system will be discussed in terms of materials and devices used in the design and application of infohybrid systems. Furthermore, we will describe how we have innovatively approached the design and development of a systematic diagram of the infohybrid for its potential use in barcoded molecular sensing, steganographic nanoforensics, item-level tagging identification, data storage, and even communication. [ABSTRACT FROM AUTHOR]

We have successfully synthesized inorganic–inorganic, organic–inorganic and bio-inorganic nanohybrids by applying an intercalation technique systematically to layered titanate, molybdenum disulfide (MoS2), Bi-based cuprate superconductors (Bi2Sr2Cam−1CumOy (m=1, 2, and 3; BSCCO)), and to layered double hydroxides (LDHs), those which are of high importance in terms of basic understanding of intercalation reactions and of their practical applications. The inorganic–inorganic systems such as TiO2-pillared titanate, TiO2-pillared MoS2, and CdS–MoS2 hybrids were synthesized by exfoliation–restacking method. A novel pillaring process using an osmotic swelling was developed to prepare TiO2-pillared layered titanate with a large surface area, high thermal stability, and enhanced photocatalytic activity. And the intercalation of TiO2 and/or CdS nanocluster into the two dimensional MoS2 lattice could be also realized by exfoliating and reassembling the lithiated molybdenum disulfide (LiMoS2) in the presence of cationic TiO2 and/or CdS nanocluster in an aqueous solution, respectively, to obtain the semiconductor–semiconductor hybrids. On the other hands, the organic–inorganic hybrids were achieved via intercalative complexation of iodine intercalated BSCOO with organic salt of Py–CnH2n+1I (Py=pyridine). The high-Tc superconducting intercalate with its remarkable lattice expansion can be applied as a precursor for superconducting colloids when dispersed in an appropriate solvent. This superconducting hybrid material had an unique structural feature of a superconducting-insulating-superconducting multilayer with atomically clean interfaces. Especially, this organic–inorganic nanohybrid is expected to be a promising precursor for preparing the superconducting colloidal suspension, which could be applied to the fabrication of superconducting films or wires. Recently, we were very successful in demonstrating in which the formation of bio-inorganic hybrids stabilized in the interlayer space of LDH retain their chemical and biological integrity. If necessary, LDH, as a reservoir, can be intentionally removed by dissolving it in an acidic media in such a way the interlayer biomolecules can be recovered or the intercalated biomolecules can be released from the LDH via ion-exchange reaction in electrolyte. It is, therefore, concluded that the inorganic LDH can play a role as a gene reservoir or carrier for various unstable organic or bio-molecules such as drugs and genes. [Copyright &y& Elsevier]

Abstract: Nanoporous inorganic materials have attracted great interest due to their potential application as nanofilters, drug delivery carriers and adsorbents. In order to control the molecular passage through nanopores, we have modified the pore channel of inorganic materials with organic moieties and investigated the diffusion pattern of small molecules. The surface was modified by octyltriethoxysilane (OTS) by refluxing in toluene for 12h. The water contact angle of OTS modified zirconia membrane was observed ∼110° showing hydrophobic surface. Contact angles to various solvents were also examined to verify the self-assembled monolayer of octyl chains on the inorganic membrane. The molecular passage patterns of both pristine and modified nanoporous membrane were evaluated by means of the diffusivity of small dye molecule, azobenzene. The diffusion coefficients of azobenzene on both membranes were measured in various solvents on the basis of Fick’s diffusion law. The diffusivities in various solvents for pristine and its modified zirconia membrane were determined. The diffusivity was observed to be influenced by surface energy of both membrane and solvent as well as the polarity of solvents. [Copyright &y& Elsevier]

• Photo-chemo-therapeutic (PCT) approaches using emerging functional nanomaterials. • Recent trends in PCT with specific attention to composite nanomaterials. • Limitations, advantages and future scope of such systems are critically evaluated. • Allow the readers to think about new modification in PCT area. Since the non-specific and non-selective modes of traditional treatments make it difficult to treat cancers, novel nano-aided technologies are necessary to fill those gaps in the current methods. Photo-Chemo Therapy (PCT) has been a cynosure as it has a great scope in the cancer management. Typically, both photo thermal (PTT) and photodynamic therapies (PDT) in combination with chemotherapy using nano-substrates have found to be beneficial. Though PCT has gained attention these days, nano assisted PCT is a budding field. This review focusses recent developments and trends in PCT approaches and implications in details which includes rise of various hybrid nanomaterials integrating PCT with imaging techniques as well as NIR (near infrared) dye based self-assembled nanostructures. Overall, this review would give readers not only an idea on new trends using different novel nano approaches in PCT, but also to help them understand its potential to improve or translate current systems for a better cancer management in near future. [ABSTRACT FROM AUTHOR]

Abstract: A new strategy was attempted to fabricate photoelectrode of dye-sensitized solar cells through a reassembly technique (exfoliation and restacking) to increase solar activity. A random hybridization between exfoliated layered titanate and TiO2 (anatase) nanoparticles resulted in a ‘house-of-cards’ structure, which might increase the mesoporosity and surface area of TiO2 film. In the XRD patterns of the present nanocomposite, no (00 l) peaks could be seen due to the random hybridization between layered titanate and TiO2 nanosol particles. According to the N2 adsorption–desorption isotherms, the resulting nanohybrids are fairly porous with a high specific surface area (S BET=∼190m2/g, mean pore size=6nm), which leads to an efficient dye adsorption. A solar energy to electricity conversion efficiency (η) of the present nanocomposite film is about 100 times higher than that of TiO2 nanoparticle one under the standard AM 1.0 irradiation condition, suggesting that the mesoporous nature of TiO2 film would play an important role for efficient photovoltaic cell performance. [Copyright &y& Elsevier]