Adsorption of aromatic compounds by carbonaceous adsorbents: a comparative study on granular activated carbon, activated carbon fiber, and carbon nanotubes.

Adsorption of three aromatic organic compounds (AOCs) by four types of carbonaceous adsorbents [a granular activated carbon (HD4000), an activated carbon fiber (ACF10), two single-walled carbon nanotubes (SWNT, SWNT-HT), and a multiwalled carbon nanotube (MWNT)] with different structural characteristics but similar surface polarities was examined in aqueous solutions. Isotherm results demonstrated the importance of molecular sieving and micropore effects in the adsorption of AOCs by carbonaceous porous adsorbents. In the absence of the molecular sieving effect, a linear relationship was found between the adsorption capacities of AOCs and the surface areas of adsorbents, independent of the type of adsorbent. On the other hand, the pore volume occupancies of the adsorbents followed the order of ACF10 > HD4000 > SWNT > MWNT, indicating that the availability of adsorption site was related to the pore size distributions of the adsorbents. ACF10 and HD4000 with higher microporous volumes exhibited higher adsorption affinities to low molecular weight AOCs than SWNT and MWNT with higher mesopore and macropore volumes. Due to their larger pore sizes, SWNTs and MWNTs are expected to be more efficient in adsorption of large size molecules. Removal of surface oxygen-containing functional groups from the SWNT enhanced adsorption of AOCs.

Facile preparation of biocompatible sulfhydryl cotton fiber-based sorbents by "thiol-ene" click chemistry for biological analysis.

Sulfhydryl cotton fiber (SCF) has been widely used as adsorbent for a variety of metal ions since 1971. Thanks to the abundant thiols on SCF, in this study, we reported a universal method for the facile preparation of SCF-based materials using "thiol-ene" click chemistry for the first time. With the proposed method, two types of SCF-based materials, phenylboronic acid grafted sulfhydryl cotton fiber (SCF-PBA) and zirconium phosphonate-modified sulfhydryl cotton fiber (SCF-pVPA-Zr(4+)), were successfully prepared. The grafted functional groups onto the thiol group of SCF were demonstrated by X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX). The prepared fibrous materials exhibited excellent fiber strength, good stability in aqueous or nonaqueous solutions, and great biocompatibility. Moreover, we developed filter-free in-pipet-tip SPE using these SCF-based materials as adsorbent for the enrichment of ribonucleosides, glycopeptides and phosphopeptides. Our results showed that SCF-PBA adsorbent can selectively capture ribonucleosides and glycopeptides from complex biological samples. And SCF-pVPA-Zr(4+) adsorbent exhibited high selectivity and capacity in the enrichment of phosphopeptides from the digestion mixture of ß-casein and bovine serum albumin (BSA), as well as human serum and nonfat milk digest. Generally, the preparation strategy can be a universal method for the synthesis of other functionalized cotton-based adsorbents with special requirement in microscale biological analysis.

The expression of cross-linked elastin by rabbit blood vessel smooth muscle cells cultured in polyhydroxyalkanoate scaffolds.

In order to evaluate the possibility for making artificial blood vessels, a series of microbial copolyesters poly(3-hydroxybutyrate-co-4-hydroxybutyrate)s (P3HB4HB)s containing 0-40 mol% 4-hydroxybutyrate (4HB) were studied for growth and formation of elastin of rabbit blood vessel smooth muscle cells (RaSMCs) incubated on the solvent-casting polyester films. Porous scaffolds of all P3HB4HBs except P(HB-40 mol% 4HB) were used to compare their potentials as materials for tissue engineering blood vessel (TEBV). The polyesters were studied using static contact angles, differential scanning calorimetry (DSC), cell count kit-8 (CCK-8) and Fastin elastin assays. Simultaneously, SEM, H&E and DAPI staining were employed to study cell morphology and cell growth in the polyester scaffolds. Viability of rabbit blood vessel smooth muscle cells (RaSMCs) grown on P(HB-7 mol% 4HB) films was the strongest among all other tested polyester films during the whole growth process. H&E and DAPI staining clearly suggested good cells' growth and even confluent growth in the P3HB4HB scaffolds. Fastin elastin assay demonstrated that 4HB component in the P3HB4HB copolymer benefited the elastin formation and accumulation. P(HB-20 mol% 4HB) showed a 160% more elastin production compared with that on the well-studied poly(3-hydroxybutyrate-co-12 mol% 3-hydroxyhexanoate) (PHBHHx) incubated under the same conditions. Since the P3HB4HB has adjustable elasticity and strength, combined with its ability to induce elastin formation, it can be regarded as a useful material for developing into a material for artificial blood vessels.

A single-strand helical coordination polymer: catena-poly[[[triaquanickel(II)]-mu-2,2'-bipyridine-3,3'-dicarboxylato-kappa(3)N,N':O] monohydrate].

The asymmetric unit of the title compound, [[Ni(C(12)H(6)N(2)O(4))(H(2)O)(3)].H(2)O](n), is composed of a lattice water molecule and a nickel(II) ion that is coordinated by three water molecules and the two N atoms of a 2,2'-bipyridine-3,3'-dicarboxylate ligand. The twist of the 2,2'-bipyridine-3,3'-dicarboxylate unit and the coordination of one carboxylate group to a symmetry-related Ni(II) atom generate a helical chain that runs along the b axis. Intrahelical hydrogen bonds participate in controlling the orientation of the helices, and both right-handed and left-handed helices are connected by interhelical hydrogen bonds into two-dimensional sheets.