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Boron neutron capture therapy (BNCT) is a binary therapeutic technique employing a boron agent to be delivered to the tumor site followed by the irradiation of neutrons. Biofunctional molecules/nanoparticles labeled with F-18 can provide an initial pharmacokinetic profile of patients to guide the subsequent treatment planning procedure of BNCT. Borono phenylalanine (BPA), recognized by the l-type amino acid transporter, can cross the blood-brain barrier and be accumulated in gliomas. The radiofluoro BNCT agents are reviewed by considering (1) less cytotoxicity, (2) diagnosing and therapeutic purposes, (3) aqueous solubility and extraction route, as well as (4), the trifluoroborate effect. A trifluoroborate-containing amino acid such as fluoroboronotyrosine (FBY) represents an example with both functionalities of imaging and therapeutics. Comparing with the insignificant cytotoxicity of clinical BPA with IC50 > 500 μM, FBY also shows minute toxicity with IC50 > 500 μM. [18F]FBY is a potential diagnostic agent for its tumor to normal accumulation (T/N) ratio, which ranges from 2.3 to 24.5 from positron emission tomography, whereas the T/N ratio of FBPA is greater than 2.5. Additionally, in serving as a BNCT therapeutic agent, the boron concentration of FBY accumulated in gliomas remains uncertain. The solubility of 3-BPA is better than that of BPA, as evidenced by the cerebral dose of 3.4%ID/g vs. 2.2%ID/g, respectively. While the extraction route of d-BPA differs from that of BPA, an impressive T/N ratio of 6.9 vs. 1.5 is noted. [18F]FBPA, the most common clinical boron agent, facilitates the application of BPA in clinical BNCT. In addition to [18F]FBY, [18F] trifluoroborated nucleoside analog obtained through 1,3-dipolar cycloaddition shows marked tumoral uptake of 1.5%ID/g. Other examples using electrophilic and nucleophilic fluorination on the boron compounds are also reviewed, including diboronopinacolone phenylalanine and nonsteroidal anti-inflammatory agents. [ABSTRACT FROM AUTHOR]

Recently, the development of anti-cancer approaches using different physical or chemical pathways has shifted from monotherapy to synergistic therapy, which can enhance therapeutic effects. As a result, enormous efforts have been devoted to developing various delivery systems encapsulated with dual agents for synergistic effects and to combat cancer cells acquired drug resistance. In this study, we show how to make Institute of Bioengineering and Nanotechnology (IBN)-1-based mesoporous silica nanoparticles (MSNs) for multifunctional drug delivery to overcome drug resistance cancer therapy. Initially, curcumin (Cur)-embedded IBN-1 nanocomposites (IBN-1-Cur) are synthesized in a simple one-pot co-condensation and then immobilized with the prodrug of Cisplatin (CP) on the carboxylate-modified surface (IBN-1-Cur-CP) to achieve photodynamic therapy (PDT) and chemotherapy in one platform, respectively, in the fight against multidrug resistance (MDR) of MES-SA/DX5 cancer cells. The Pluronic F127 triblock copolymer, as the structure-directing agent, in nanoparticles acts as a p-glycoprotein (p-gp) inhibitor. These designed hybrid nanocomposites with excellent structural properties are efficiently internalized by the endocytosis and successfully deliver Cur and CP molecules into the cytosol. Furthermore, the presence of Cur photosensitizer in the nanochannels of MSNs resulted in increased levels of cellular reactive oxygen species (ROS) under light irradiation. Thus, IBN-1-Cur-CP showed excellent anti-cancer therapy in the face of MES-SA/DX5 resistance cancer cells, owing to the synergistic effects of chemo- and photodynamic treatment. [ABSTRACT FROM AUTHOR]

The adsorption property of small toxic gaseous molecules (SO2, SO3, H2S, and N2O) with metal/hexa‐vacancy defective graphene (denoted as HDG‐M, M: Fe2+, Co2+, Ni2+, Cu2+, and Zn2+) was determined by density functional theory. The results of these calculations show that the Fe2+ ion has the best and Cu2+ the worst absorption ability to capture all of the above toxic gases with selected adsorption orientation. These results can provide useful information for the application of the designed HDG‐M adsorbents in food science and ecosystem monitoring. [ABSTRACT FROM AUTHOR]

The surface of gold nanorods is chemically charged by ascorbic acid; the charging effect results in not only the blue shift on their surface plasmon bands, but also the change of the deposition rate of silver on their surfaces. The rate was prominently accelerated at room temperature, but slightly slowed down at higher temperature. The shape of gold‐silver core‐shell nanoparticles could not be obviously affected. The Fermi level of gold nanorods begins to increase under the action of charging and alters the electrical double‐layer structure of gold nanorods, resulting in the different deposition rate of silver on gold. [ABSTRACT FROM AUTHOR]

Density functional theory was applied to calculate the adsorption property of metal/hexa-vacancy defective graphene (denoted as HDG-M, M: Fe 2+ , Co 2+ , Ni 2+ , Cu 2+ and Zn 2+ ) with O- and N-dopants. We investigate the adsorption properties of these complexes between gaseous molecules and HDG-M. Our results show that HDG-Cu has a high selectivity for O 2 , but HDG-Fe has a good ability to capture many gases such as CO, NO and O 2 . Our calculations could provide useful information for designing new graphene-based adsorbents to remove undesired gases, which may poison the metal catalysts in reaction processes. [ABSTRACT FROM AUTHOR]

Highlights: [•] We report a simple and effective method to synthesize gold nanodumbbells (NDs). [•] Gold NDs are used to synthesize gold–silver core–shell nanoparticles (Au@Ag NPs). [•] Au@Ag NPs with bar and triangular bipyramid shapes were obtained at high temperature. [•] Gold NDs in Au@Ag nanobars are in the center position of bar NPs. [•] The longer end of Au ND is parallel to the shorter edge of triangular bipyramid NP. [ABSTRACT FROM AUTHOR]

The surface modification of two-dimensional (2D) nanocontainers with versatile chemical functionalities offers enormous advantages in medicine owing to their altered physicochemical properties. In this study, we demonstrate the fabrication of surface-functionalized layered double hydroxides (LDHs) towards their use as effective intestinal bile acid sequestrants. To demonstrate these aspects, the LDHs are initially modified with an amino silane, N1-(3-trimethoxysilylpropyl) diethylenetriamine (LDHs-N3), which, on the one hand, subsequently used for the fabrication of the dendrimer by repetitive immobilization of ethylene diamine using methyl acrylate as a spacer. On the other hand, these surface-functionalized LDHs are wrapped with an anionic enteric co-polymer to not only prevent the degradation but also increase the stability of these 2D nanoplates in an acidic environment of the stomach to explore the in vivo efficacy. In vitro cholic acid adsorption results showed that these surface-functionalized LDHs displayed tremendous adsorption ability of bile salt. Consequently, the bile salt adsorption results in vivo in mice confirmed that the enteric polymer-coated diethylenetriamine silane-modified LDHs, resulting in the reduced cholesterol by 8.2% in the high fat diet-fed mice compared to that of the oil treatment group with augmented 28% of cholesterol, which gained weight by 6.7% in 4 weeks. Notably, the relative organ (liver and kidney) weight analysis and the tissue section of histology results indicated that the modified LDHs showed high biocompatibility in vivo. Together, our findings validate that these surface-functionalized 2D nanoplates have great potential as effective intestinal bile acid sequestrants. [ABSTRACT FROM AUTHOR]

The benefits of increasing the number of surface hydroxyls on TiO₂ nanoparticles (NPs) are known for environmental and energy applications; however, the roles of the hydroxyl groups have not been characterized and distinguished. Herein, TiO₂ NPs with abundant surface hydroxyl groups were prepared using commercial titanium dioxide (ST-01) powder pretreated with alkaline hydrogen peroxide. Through this simple treatment, the pure anatase phase was retained with an average crystallite size of 5 nm and the surface hydroxyl group density was enhanced to 12.0 OH/nm², estimated by thermogravimetric analysis, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Especially, this treatment increased the amounts of terminal hydroxyls five- to six-fold, which could raise the isoelectric point and the positive charges on the TiO₂ surface in water. The photocatalytic efficiency of the obtained TiO₂ NPs was investigated by the photodegradation of sulforhodamine B under visible light irradiation as a function of TiO₂ content, pH of solution, and initial dye concentration. The high surface hydroxyl group density of TiO₂ NPs can not only enhance water-dispersibility but also promote dye sensitization by generating more hydroxyl radicals., Competing Interests: The authors declare no conflict of interest.

To develop a carrier for use in enzyme prodrug therapy, Horseradish peroxidase (HRP) was immobilized onto mesoporous silica nanoparticles (IBN-4: Institute of Bioengineering and Nanotechnology), where the nanoparticle surfaces were functionalized with 3-aminopropyltrimethoxysilane and further conjugated with glutaraldehyde. Consequently, the enzymes could be stabilized in nanochannels through the formation of covalent imine bonds. This strategy was used to protect HRP from immune exclusion, degradation and denaturation under biological conditions. Furthermore, immobilization of HRP in the nanochannels of IBN-4 nanomaterials exhibited good functional stability upon repetitive use and long-term storage (60 days) at 4 °C. The generation of functionalized and HRP-immobilized nanomaterials was further verified using various characterization techniques. The possibility of using HRP-encapsulated IBN-4 materials in prodrug cancer therapy was also demonstrated by evaluating their ability to convert a prodrug (indole-3- acetic acid (IAA)) into cytotoxic radicals, which triggered tumor cell apoptosis in human colon carcinoma (HT-29 cell line) cells. A lactate dehydrogenase (LDH) assay revealed that cells could be exposed to the IBN-4 nanocomposites without damaging their membranes, confirming apoptotic cell death. In summary, we demonstrated the potential of utilizing large porous mesoporous silica nanomaterials (IBN-4) as enzyme carriers for prodrug therapy.

Optimized geometries and electronic structures of two different hexagonal grapheme nanosheets (HGNSs), with armchair (n-A-HGNS, n = 3-11) and zigzag (n-Z-HGNS, n = 1-8) edges have been calculated by using the GGA/PBE method implemented in the SIESTA package, with the DZP basis set, where n represents the number of peripheral rings. The computed HOMO-LUMO energy gap (Eg = ELUMO - EHOMO) decreases for fully H-terminated A- and Z-HGNSs with increasing n, i.e., with increasing nanosheet size and pπ-orbitals being widely delocalized over the sheet surface. The full terminations, calculated with various functional groups, including the electron-withdrawing (F-, Cl-, and CN-) and -donating (OH-, and SH-) substitutions, were addressed. Significant lowering of EHOMO and ELUMO was obtained for CN-terminated HGNS as compared to those for H-terminated ones due to the mesomeric effect. The calculated Eg value decreases with increasing n for all terminations, whereby for the SH-termination in HGNS, the termination effect becomes less significant with increasing n. Further, the calculation results for stabilities of HGNS oxides support the tendency toward the oxidative reactivity at the edge site of the sheet, which shows most pronounced C-C bond length alternation, by chemical modification. Physical properties of HGNSs with various numbers of the core-defects, which can be obtained by strong oxidation, were also investigated. Their structures can change drastically from planar to saddle-like shapes. These conformations could be used as stationary phases with controlled interaction in the separation methods such as HPLC and the other chemical analysis techniques.

Optimized geometries and electronic structures of hydrogenated silicon nanoclusters, which include the Td and Ih symmetries, have been generated by using the semiempirical AM1 and PM3 methods, the density functional theory (DFT) B3LYP method with the 6-31G(d) and LANL2DZ basis sets from the Gaussian 03 package, and the local density functional approximation (LDA), which is implemented in the SIESTA package. The calculated diameters for these Td symmetric hydrogenated silicon nanoclusters are in the range from 6.61 A (Si5H12) to 23.24 A (Si281H172). For the Ih symmetry, we calculated Si20H20 and Si100H60 nanoclusters only. Theoretically, the energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) is size dependent. The calculated energy gap decreases (Si5H12: 7.65 eV to Si281H172: 3.06 eV) while the diameter of silicon nanocluster increases. By comparing different calculated results, we concluded that the calculated energy gap by B3LYP/6-31G(d)//LDA/SIESTA is close to that from experiment and that the LDA/SIESTA result underestimates the experimental value. On the contrary, the AM1 and PM3 results overestimate the experimental results. For investigation of the optical properties of Si nanoclusters as a function of surface passivation, we carried out a B3LYP/6-31G(d)//LDA/SIESTA calculation of the Si35 and Si47 core clusters with full alkyl-, OH-, NH2-, CH2NH2-, OCH3-, SH-, C3H6SH-, and CN- passivations. The calculated optical properties of alkyl passivated Si35 nanoclusters (Si35(CH3)36, Si35(C2H5)36, and Si35(C3H7)36) are close to one another and are higher than those of oxide, nitride, and sulfide passivated Si 35 clusters. In conclusion, the alkyl passivant affects weakly the calculated optical gaps, and the electron-withdrawing passivants generate a red-shift in the energy gap of silicon nanoclusters. A size-dependent effect is also observed for these passivated Si nanoclusters.

Gold nanoparticles prepared by chemical reduction in sodium dodecyl sulfate (SDS) solution are size-controlled with the addition of pyrene. Micellar electrokinetic capillary chromatography (MEKC) is applied to the system to examine the size and polydispersity of gold nanoparticles and to show that pyrene has the extraordinary effect in decreasing the size and narrowing the dispersity of gold nanoparticles. The MEKC electropherograms further suggest that pyrene could be oxidized by the aqueous Au(III) complexes first. All the reduced Au complexes were then solubilized in the pyrene-SDS micelles. The growth of gold nanoparticles beyond the embryonic stage was subsequently inhibited by the encapsulating SDS and electrophilic pyrene.