Efficient capture and highly sensitive analysis of okadaic acid by three-dimensional covalent organic frameworks with hydroxyl surface engineering.

A novel three-dimensional covalent organic framework (3D-COF) with content-tunable and active hydroxyl groups (OH) on the pore walls was developed and adopted for the high-performance capture of okadaic acid (OA) marine toxins. Using pore-surface engineering, the integration of linear building blocks (4,4'-diamino-3,3'-biphenyldiol, BD(OH) and benzidine, BD) with the 3D structural building block backbone (4,4',4'',4'''-methane-tetrayltetrabenzaldehyde, TFPM) was achieved. By adjusting the ratio of BD(OH), functional multicomponent-COFs [OH]-BD-TFPM COFs (X = 25%) were synthesized, which offered ideal access to convert a conventional COF into a functional platform with multiple-mode interactions of hydrophobic and hydrophilic groups for OA capture.

Towards highly specific aptamer-affinity monolithic column by efficient UV light-initiated polymerization in "one-pot".

Time-consuming or tedious operation in multiple-step process might is the obstacle for efficiently preparing aptamer-affinity monolithic column. Here, a new and facile strategy to prepare aptamer-based hybrid affinity monolith in "one-pot" at room temperature was exploited, in which UV light-initiated free-radical polymerization and "thiol-ene" click reaction were implemented simultaneously. Only 7 min was cost for finishing the polymerization reaction, which was only 1/100 of that for the traditional thermal polymerization.

Heteroporous 3D covalent organic framework-based magnetic nanospheres for sensitive detection of bisphenol A.

Covalent organic frameworks (COFs) showed great promise in effective adsorption of target molecule via size selectivity. Although various magnetic 2D COFs composites have been studied and exhibited the intensive applications, the incorporation of 3D COFs and magnetic nanoparticles to form a new class of magnetic adsorbents with enhanced function still has no reports. Herein, a novel FeO@3D COF with heteroporous structure matching to the sizes of bisphenol A (BPA) was firstly synthesized for better adsorption of BPA than common magnetic 2D-COFs.

Facile preparation of stainless steel microextraction fiber via in situ growth of metal-organic framework UiO-66 and its application to sensitive analysis of polycyclic musks.

A functional stainless steel microextraction fiber easily prepared by in situ growing metal-organic framework UiO-66 was presented and used for high-performance analysis of polycyclic musks. Via the robust Ag-SH bonding reaction, mercaptoacetic acid was easily anchored on Ag film to provide carboxyl group on the stainless steel fiber, then in situ grown UiO-66 was fulfilled via the coordination reaction between Zr and carboxyl group. Good characteristics including large surface area, high thermal stability, and good adsorption property were achieved.

Highly hydrophilic polyhedral oligomeric silsesquioxane (POSS)-containing aptamer-modified affinity hybrid monolith for efficient on-column discrimination with low nonspecific adsorption.

A novel polyhedral oligomeric silsesquioxane (POSS)-containing aptamer-modified hybrid affinity monolith with excellent hydrophilicity and unique architecture without Si-OH groups is presented herein, and the nonspecific adsorption caused by the hydrophobic nature of the monolithic column or polar interaction with silanol groups is minimized. Via a simple "one-pot" procedure, hydrophilic monomers were facilely polymerized with the POSS-methacryl substituted (POSS-MA) and aptamer; a highly hydrophilic nature was obtained and the lowest contact angle of 11° was achieved. By using ochratoxin A (OTA) as the model analyte, highly selective recognition of OTA in the mixture was achieved and the control of nonspecific interactions and the cross-reactivity of OTB and AFB1 were significantly improved.

Study on the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chloro-phenoxyacetic sodium (MCPA sodium) in natural agriculture-soils of Fuzhou, China using capillary electrophoresis.

A new method of analyzing trace 2,4-Dichlorophenoxyacetic acid (2,4-D) and 2-methy-4-chloro-lphenoxyacetic sodium (MCPA sodium) in soils by capillary electrophoresis (CE) has been developed in this study. The optimum analytical conditions including chemical component and concentration of buffer solution, pH, separation voltage and sample injection time were studied in detail. Under the optimum conditions, 2,4-D and MCPA sodium in soils can be speedy separated and determined within 20 min with detection limits of 0.