Since the discovery of a new family of mesoporous silicate materials, denoted M41S and including , by researchers at Mobil, [1] major developments have been made in this field. A great variety of mesostructures has been obtained, including mesoporous silica, metal oxides, metals, carbon, and hybrid organosilicates. [2] Up to now, the main research efforts have concentrated on the MCM-41 silica structure, which consists of a hexagonal packing of one-dimensional (1D) channels (p6mm), and fewer investigations have been reported on mesoporous MCM-48, which has a 3D bicontinuous mesostructure (Ia3d). This may result from the small domain of this cubic phase (Ia3d) of MCM-48 in phase diagrams. Several methodologies have been developed for the syntheses of mesoporous silica MCM-48 by using a cationic alkylammonium surfactant, [1, 3] mixed cationic/anionic surfactants, [4] or cationic/nonionic surfactants as templates. [5] Generally, these syntheses were carried out under the severe conditions of high-temperature (! 100 8C) hydrothermal synthesis in alkaline aqueous media. Relatively expensive ionic surfactants were employed, and the resulting mesostructures have a limited range of small pore sizes (pore diameter 1.5±4.5 nm). These restrictions may limit the potential applications of 3D bicontinuous mesoporous materials as adsorbents, separators, and catalysts.Here we report the synthesis of large-pore 3D bicontinuous mesoporous silica (designated FDU-5) at room temperature in acidic media by using a commercial nonionic triblock copolymer as template and an organosiloxane or organic compound as additive. To the best of our knowledge, this is the first preparation of Ia3d mesostructured material at room temperature under acidic conditions. The FDU-5 products have uniform large pores (4.5±9.5 nm). Such mesoporous materials with large 3D bicontinuous pores could have applications in sorption and transport, especially of large molecules.Large-pore 3D bicontinuous mesoporous FDU-5 was synthesized at room temperature in ethanol solution by a solvent-evaporation method. Triblock poly(ethylene oxide)b-poly(propylene oxide)-b-poly(ethylene oxide) copolymer (EO 20 PO 70 EO 20 , P123) was used as template, tetraethyl orthosilicate (TEOS) as silica source, and a small amount of 3-mercaptopropyltrimethoxysilane (MPTS), benzene, or a benzene derivative (methyl-, ethyl-, dimethyl-, or trimethylbenzene) as additive.Transmission electron microscopy (TEM) images and corresponding Fourier diffractograms recorded along the [100], [111], [110], and [331] directions of calcined FDU-5 silica prepared with P123 as template and MPTS as additive in acidic medium at room temperature are shown in Figure 1. These images clearly show that the products have large domains of ordered 3D bicontinuous mesostructure. The two principal directions displaying continuous pores are [100] and [111] (Figure 1 a,b), and two types of hexagonally packed dots with different sizes and darknesses (Figure 1 b) are clearly observed. The images shown in Figure 1 are be...
We present the use of conductive spray polymer ionization mass spectrometry (CPSI-MS) combined with machine learning (ML) to rapidly gain the metabolic fingerprint from 1 μl liquid extraction from the biopsied tissue of triple-negative breast cancer (TNBC) in China. The 76 discriminative metabolite markers are verified at the primary carcinoma site and can also be successfully tracked in the serum. The Lasso classifier featured with 15- and 22-metabolites detected by CPSI-MS achieve a sensitivity of 88.8% for rapid serum screening and a specificity of 91.1% for tissue diagnosis, respectively. Finally, the expression levels of their corresponding upstream enzymes and transporters have been initially confirmed. In general, CPSI-MS/ML serves as a cost-effective tool for the rapid screening, diagnosis, and precise characterization for the TNBC metabolism reprogramming in the clinical practice.
Seeded growth of crystallizable block copolymers and π-stacking molecular amphiphiles in solution using the living crystallization-driven self-assembly (CDSA) method is attracting growing interest as a route to uniform 1D and 2D core–shell micellar nanoparticles of controlled size with a range of potential applications. Although experimental evidence indicates that the process proceeds via an epitaxial growth mechanism and that the resulting crystalline core is highly ordered, direct observation of the crystal lattice has not been successful. Herein we report the results of high-resolution cryo-TEM studies that permit direct observation of both the solvated corona chains and the crystalline core from studies of frozen solution of nanofiber micelles prepared by living CDSA. Together with complementary characterization data, this provides key insight into the structure of the corona and the detailed arrangement of the polymer chains in the crystalline micellar nanofiber core.
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