Fragmented α-Amylase into Microporous Metal-Organic Frameworks as Bioreactors.

This work presents an efficient and facile strategy to prepare an α-amylase bioreactor. As enzymes are quite large to be immobilized inside metal-organic frameworks (MOFs), the tertiary and quaternary structures of α-amylase were first disrupted using a combination of urea, dithiothreitol (DTT), and iodoacetamide (IAA). After losing its tertiary structure, the unfolded proteins can now penetrate into the microporous MOFs, affording fragmented α-amylase@MOF bioreactors.

Fast multipoint immobilization of lipase through chiral L-proline on a MOF as a chiral bioreactor.

In this paper, we describe the facile preparation of a chiral catalyst by the combination of the amino acid, l-proline (Pro), and the enzyme, porcine pancreas lipase (PPL), immobilized on a microporous metal-organic framework (PPL-Pro@MOF). The multipoint immobilization of PPL onto the MOF is made possible with the aid of Pro, which also provided a chiral environment for enhanced enantioselectivity. The application of the microporous MOF is pivotal in maintaining the catalytic activity of PPL, wherein it prevented the leaching of Pro during the catalytic reaction, leading to the enhanced activity of PPL.

A simple approach to achieve a metastable metal oxide derived from carbonized metal-organic gels.

A strategy for fabricating zirconium oxide doped nanoporous carbons derived from metal-organic gels (MOGs) is reported. For the first time, the achievement of metastable ZrO2-NPCs is demonstrated. The direct pyrolysis of MOGs provided new perspective in developing metal oxide-doped NPCs and circumvented the shortcomings of existing methods in synthesizing metastable ZrO2 doped NPCs.

β-secretase 1 inhibitory activity and AMP-activated protein kinase activation of extracts.

The methanolic extract of (MCS) significantly inhibited β-secretase 1 (IC 99.82 µg/mL) in a dose-dependent manner and demonstrated a noncompetitive type of inhibition. Furthermore, it exhibited the highest AMPK activation (EC 14.

Monitoring the Effect of Different Metal Centers in Metal-Organic Frameworks and Their Adsorption of Aromatic Molecules using Experimental and Simulation Studies.

In this study, the adsorption behavior of different metal centers in analogous M-1,4-NDC frameworks (1,4-NDC=1,4-naphthalenedicarboxylate) towards guest molecules through simulation studies and experimental studies is reported. Simulation studies showed that the adsorption behavior of analogous M-1,4-NDC is affected by the atomic radius of the metal center, which was found to be in agreement with the experimental studies.

The Cooperativity of Fe O and Metal-Organic Framework as Multifunctional Nanocomposites for Laser Desorption Ionization Process.

A novel and facile strategy in developing a water stable magnetic metal-organic framework nanocomposite (Fe O @MOF) is herein reported, in which a Keggin polyoxometalate, phosphotungstic acid (HPW), was encapsulated within the MOF framework via one-pot synthesis method. The combination of HPW-embedded MOF and Fe O endowed the composite with high surface area, strong UV absorption, good hydrophilicity, and enhanced water stability. With these unique properties, the Fe O @MOF embedded HPW served as adsorbent as well as matrix for SALDI-MS (surface-assisted laser desorption ionization mass spectrometry) analysis of polar and non-polar compounds.

Application of mesoporous carbon-polymer monolith for the extraction of phenolic acid in food samples.

In this study, activated carbon-organic polymer (AC-polymer) extraction columns were prepared via microwave-assisted polymerization. The AC-polymer was applied in polymer monolith microextraction (PMME) of phenolic acids (PAs) in food samples. Structural characterization using Raman and Fourier transform infrared (FTIR) spectroscopy revealed the successful incorporation of AC into polymer monolith.

Pore Environment Control and Enhanced Performance of Enzymes Infiltrated in Covalent Organic Frameworks.

In the drive toward green and sustainable methodologies for chemicals manufacturing, biocatalysts are predicted to have much to offer in the years to come. That being said, their practical applications are often hampered by a lack of long-term operational stability, limited operating range, and a low recyclability for the enzymes utilized. Herein, we show how covalent organic frameworks (COFs) possess all the necessary requirements needed to serve as ideal host materials for enzymes.

Synthesis and characterization of trimetallic cobalt, zinc and nickel complexes containing amine-bis(benzotriazole phenolate) ligands: efficient catalysts for coupling of carbon dioxide with epoxides.

New trimetallic cobalt, nickel and zinc complexes 1-3 coordinated by amine-bis(benzotriazole phenolate) ligands and ancillary acetate groups have been developed for the use of CO/epoxide coupling. All complexes were structurally characterized by single crystal X-ray crystallography; tri-Co complex 1 is the first solid-state example in which three different geometrical configurations exist in the same benzotriazole phenoxide metal complex. Tri-nuclear complexes 1 and 2 with cobalt and zinc metal centers were demonstrated to be very active catalysts for cycloaddition of cyclohexene oxide with CO in the presence of ammonium salt co-catalysts to give cis-cyclohexene carbonate under the conditions of 80 °C and 300 psi initial CO pressure.

Nitrogen-doped porous carbon material derived from metal-organic gel for small biomolecular sensing.

A simple preparation method of N-doped PCM via direct carbonization of nitrogen containing metal-organic gel was demonstrated. The resultant N-PCM, with high surface area, mesoporosity, and high UV absorption ability, was used as a matrix to assist small-biomolecule sensing in laser desorption/ionization mass spectrometry.

Enzyme Immobilized on Nanoporous Carbon Derived from Metal-Organic Framework: A New Support for Biodiesel Synthesis.

In this study, nanoporous carbon (NPC) derived from metal-organic framework was used as support for the immobilization of Burkholderia cepacia lipase. The decorated aluminum oxide within the mesoporous NPC improved the enzyme loading efficiency as well as the catalytic ability for the transesterification of soybean oil, thus making it a promising green and sustainable catalytic system for industrial application.

A Simple Approach to Enhance the Water Stability of a Metal-Organic Framework.

A facile method to improve the feasibility of water-unstable metal-organic frameworks in an aqueous environment has been developed that involves imbedding in a polymer monolith. The effect of compartment type during polymerization plays a significant role in maintaining the crystalline structure and thermal stability of the MOFs, which was confirmed by powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA), respectively. The MOF-polymer composite prepared in a narrow compartment (column, ID 0.

Metal-Organic Framework-Polymer Composite as a Highly Efficient Sorbent for Sulfonamide Adsorption and Desorption: Effect of Coordinatively Unsaturated Metal Site and Topology.

In this study, we first demonstrated the effect of two types of metal-organic framework-polymer (MOF-polymer) monoliths on in-tube solid-phase microextraction (IT-SPME) of sulfonamides. Sulfonamides were successfully adsorbed onto MIL-101(Cr)-polymer but were difficult to elute due to these sulfonamides could interact via Lewis acid-base interaction with the presence of Cr(III) coordinatively unsaturated metal sites (CUS). Moreover, the cage-type topology of MIL-101(Cr) that could produce multiple pathways thus complicates the desorption of the test analytes from the sorbent.

Solid-phase microextraction of phthalate esters in water sample using different activated carbon-polymer monoliths as adsorbents.

In this study, the application of different activated carbon-polymer (AC-polymer) monoliths as adsorbents for the solid-phase microextraction (SPME) of phthalate esters (PAEs) in water sample were investigated. The activated carbon (AC) was embedded in organic polymers, poly(butyl methacrylate-co-ethylene dimethacrylate) (poly(BMA-EDMA)) or poly(styrene-co-divinylbenzene) (poly(STY-DVB)), via a 5-min microwave-assisted or a 15-min water bath heating polymerization. Preliminary investigation on the performance of the native poly(BMA-EDMA) and poly(STY-DVB) demonstrated remarkable adsorption efficiencies for PAEs.

In vitro angiotensin I converting enzyme inhibition by a peptide isolated from Chiropsalmus quadrigatus Haeckel (box jellyfish) venom hydrolysate.

The anti-angiotensin I converting enzyme activity of box jellyfish, Chiropsalmus quadrigatus Haeckel venom hydrolysate was studied. The venom extract was obtained by centrifugation and ultrasonication. Protein concentration of 12.

Nanoporous Carbons Derived from Metal-Organic Frameworks as Novel Matrices for Surface-Assisted Laser Desorption/Ionization Mass Spectrometry.

Surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) represents a powerful tool for the analysis of biomolecules, synthetic polymers, and even small organic compounds; its performances largely depend on the type of matrix materials utilized. Here, for the first time the employment of nanoporous carbons derived from metal-organic frameworks (MOFs) as novel matrices for SALDI-MS is demonstrated. The nanoporous carbons derived from MOFs not only circumvent the shortcomings of existing matrix materials but also demonstrate much higher efficiency of laser desorption/ionization for various compounds than any other nanoporous carbons reported so far.

Determination of imidazole derivatives by micellar electrokinetic chromatography combined with solid-phase microextraction using activated carbon-polymer monolith as adsorbent.

In this study, an effective method for the separation of imidazole derivatives 2-methylimidazole (2-MEI), 4- methylimidazole (4-MEI) and 2-acetyl-4-tetrahydroxybutylimidazole (THI) in caramel colors using cation-selective exhaustive injection and sweeping micellar electrokinetic chromatography (CSEI-sweeping-MEKC) was developed. The limits of detection (LOD) and quantitation (LOQ) for the CSEI-sweeping-MEKC method were in the range of 4.3-80μgL(-1) and 14-270μgL(-1), respectively.

A novel type of matrix for surface-assisted laser desorption-ionization mass spectrometric detection of biomolecules using metal-organic frameworks.

A 3D metal-organic framework (MOF) nanomaterial as matrix for surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) and tandem mass spectrometry (MS/MS) was developed for the analysis of complex biomolecules. Unlike other nanoparticle matrices, this MOF nanomaterial does not need chemical modification prior to use. An exceptional signal reproducibility as well as very low background interferences in analyzing mono-/di-saccharides, peptides and complex starch digests demonstrate its high potential for biomolecule assays, especially for small molecules.

Aluminum based metal-organic framework-polymer monolith in solid-phase microextraction of penicillins in river water and milk samples.

In this study, aluminum based metal-organic framework (Al-MOF)-organic polymer monoliths were prepared via microwave-assisted polymerization of ethylene dimethacrylate (EDMA), butyl methacrylate (BMA) with different weight percentages of Al-MOF (MIL-53; 37.5-62.5%) and subsequently utilized as sorbent in solid-phase microextraction (SPME) of penicillins (penicillin G, penicillin V, oxacillin, cloxacillin, dicloxacillin, nafcillin).

A poly(alkyl methacrylate-divinylbenzene-vinylbenzyl trimethylammonium chloride) monolithic column for solid-phase microextraction.

In this study, an organic polymer monolithic columns, which were prepared via in situ polymerization of alkyl methacrylate-ester (AMA), divinylbenzene (DVB) and vinylbenzyl trimethylammonium chloride (VBTA, charged monomer), were developed as adsorbent for solid-phase microextraction (SPME). Different parameters affecting the extraction efficiency for nine (9) non-steroidal anti-inflammatory drugs (NSAIDs) such as the ratio of the stearyl methacrylate (SMA) to DVB monomer, column length, sample pH, extraction flow rate and desorption solvent were investigated to obtain the optimal SPME condition. Also, the permeability for each poly(AMA-DVB-VBTA) monolithic column was investigated by adding porogenic solvent (poly(ethylene glycol), PEG).

Lipase-supported metal-organic framework bioreactor catalyzes warfarin synthesis.

A green and sustainable strategy synthesizes clinical medicine warfarin anticoagulant by using lipase-supported metal-organic framework (MOF) bioreactors (see scheme). These findings may be beneficial for future studies in the industrial production of chemical, pharmaceutical, and agrochemical precursors.

Fast multipoint immobilized MOF bioreactor.

An enzyme-NBD@MOF bioreactor with exemplary proteolytic performance, even after successive reuse and storage, was produced through a novel, rapid and simple multipoint immobilization technique without chemical modification of the solid support. Enzyme loading and distribution could be directly monitored from the fluorescence emission of the bioreactor. The dye molecular dimension plays a role in its overall performance.

A novel hybrid metal-organic framework-polymeric monolith for solid-phase microextraction.

This study describes the fabrication of a novel hybrid metal-organic framework- organic polymer (MOF-polymer) for use as a stationary phase in fritless solid-phase microextraction (SPME) for validating analytical methods. The MOF-polymer was prepared by using ethylene dimethacrylate (EDMA), butyl methacrylate (BMA), and an imidazolium-based ionic liquid as porogenic solvent followed by microwave-assisted polymerization with the addition of 25 % MOF. This novel hybrid MOF-polymer was used to extract penicillin (penicillin G, penicillin V, oxacillin, cloxacillin, nafcillin, dicloxacillin) under different conditions.

Determination of amino acids by microemulsion electrokinetic chromatography laser induced fluorescence method.

In this study, detection of 20 FITC-derivatized amino acids using an MEEKC-LIF was demonstrated. In order to achieve good separation for hydrophobic amino acids, the MEEKC method was employed and detection limits were obtained in the range of 0.32-2.

Analyses of polycyclic aromatic hydrocarbons in seafood by capillary electrochromatography-atmospheric pressure chemical ionization/mass spectrometry.

In this work, an on-line preconcentration capillary electrochromatographic (CEC) separation coupled with atmospheric pressure chemical ionization-mass spectrometry (APCI-MS) was used for 16 PAHs analyses, in which poly(stearyl methacrylate-divinylbenzene) (poly(SMA-DVB)) monolith was used as the separation column. With variations in the effective length of poly(SMA-DVB) monolith as well as the volume fraction of acetonitrile (ACN) in the mobile phase, both separation and resolution were improved. A poly(SMA-DVB) monolith of 50-cm effective length (i.