Oxidized carbon nanotubes are tested as a matrix for analysis of small molecules by matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). Compared with nonoxidized carbon nanotubes, oxidized carbon nanotubes facilitate sample preparation because of their higher solubility in water. The matrix layer of oxidized carbon nanotubes is much more homogeneous and compact than that of nonoxidized carbon nanotubes. The efficiency of desorption/ionization for analytes and the reproducibility of peak intensities within and between sample spots are greatly enhanced on the surface of oxidized carbon nanotubes. The advantage of the oxidized carbon nanotubes in comparison with ␣-cyano-4-hydroxycinnamic acid (CCA) and carbon nanotubes is demonstrated by MALDI-TOF-MS analysis of an amino acid mixture. The matrix is successfully used for analysis of synthetic hydroxypropyl ␤-cyclodextrin, suggesting a great potential for monitoring reactions and for product quality control. Reliable quantitative analysis of jatrorrhizine and palmatine with a wide linear range (1-100 ng/mL) and good reproducibility of relative peak areas (RSD less than 10%) is achieved using this matrix. Concentrations of jatrorrhizine (8.65 mg/mL) and palmatine (10.4 mg/mL) in an extract of Coptis chinensis Franch are determined simultaneously using the matrix and a standard addition method. [27] developed a method for quantitative analysis of small molecules with desorption/ionization on porous silicon using electrospray deposition of analytes, and a quite good quantitative result with linear calibrations R 2 Ͼ 0.99 and values of RSD Ͻ 7% was achieved. It is believed that MALDI could be a powerful technique to provide both qualitative and quantitative determination of small compounds.Carbon nanotubes have been attracting wide interest [28,29] of scientists since they were initially discovered by Iijima et al. [30,31]. Recently, Carbon nanotubes have been developed as the matrix for MALDI-TOF-MS for analysis of small molecules [25], in which carbon nanotubes function both as the energy receptacle for laser radiation and as the energy transporter for desorption/ionization of analytes with the minimization of interference signals caused by matrix ion. The effectiveness of the method as matrix has been demonstrated by several compounds with low molecular weight. However, the low solubility of carbon nanotubes in water or organic solvent makes it hard to deposit carbon nanotubes onto the sample target and to form a homogeneous layer of matrix, leading to the relatively poor reproducibility and resolution of peaks for analytes.

There are several researches on the preparation and application of hydrazone-linked covalent organic frameworks (COFs), and all of them generally necessitate rigid aromatic amines. Herein, we report a strategy for design and synthesis of COF with flexible alkyl amine as a building block and intramolecular hydrogen bonding as a knot in the network. The proof-of-concept design was demonstrated by exploring 1,3,5-triformylphloroglucinol and oxalyldihydrazide (ODH) as precursors to synthesize a novel COF material (TpODH), in which different organic building units are combined through hydrazone bonds to form twodimensional porous frameworks. It should be pointed that irreversible enol-to-keto tautomerism and intramolecular N−H•••OC hydrogen bonding of TpODH would enhance the crystallinity and chemical stability, leading to large specific surface area of 835 m 2 g −1 . However, another COF synthesized with 1,3,5-triformylbenzene and ODH exhibited less crystallinity and low special surface area (94 m 2 g −1 ). Representatively, the resulting TpODH afforded Cu(II) and Hg(II) capacities of 324 and 1692 mg g −1 , respectively, which exceeded that of most COFs previously reported. Moreover, the Fourier-transform infrared and X-ray photoelectron spectroscopy spectra analyses were taken to demonstrate the adsorption mechanism. These results suggested that the materials could be applied to the removal of metallic ions in the future.

Perphenylcarbamoylated β-cyclodextrin-silica (Ph-β-CD-silica) hybrid monolithic columns for enantioseparation in capillary liquid chromatography (cLC) have been prepared by a "one-pot" approach via the polycondensation of alkoxysilanes and in situ copolymerization of mono (6(A)-N-allylamino-6(A)-deoxy)-Ph-β-CD and vinyl group on the precondensed siloxanes. The morphologies of the Ph-β-CD-silica hybrid monolithic columns were characterized by optical microscopy and scanning electron microscopy (SEM), showing the uniform monolithic matrixes tightly bonded onto the capillary wall. The content of Ph-β-CD incorporated in monolithic matrix by the "one-pot" approach was ca. 2.9 times higher than that by postmodification method. The permeability of the Ph-β-CD-silica chiral hybrid monolithic column was 3.63 × 10(-14) m(2), and the minimum plate height was 12 μm corresponding to 83,300 theoretical plates/meter. Enantioseparations of 13 racemates were achieved by the Ph-β-CD-silica hybrid monolithic column. In this work, since the prepolymerization system mainly consisted of organic solvent (methanol (MeOH), N,N-dimethylformamide (DMF)), the limitation and difficulty of the use of water insoluble organic monomers in the previously reported "one-pot" method was circumvented. Therefore, various β-CD derivatives as well as other hydrophobic monomers could thus be used to prepare organic-silica hybrid monolithic columns with the "one-pot" process.