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The rational integration of chemotherapy and hydroxyl radical (·OH)-mediated chemodynamic therapy (CDT) via functional metal-organic frameworks (MOF) carriers has great potential in cancer therapy. In this work, aminotriazole (3-AT) doped polyhedral metal organic frameworks (denoted as MAF) were prepared by template ligand replacement, where CDT was initiated by Cu2+/Cu+ modulated Fenton reaction and enhanced by effectively regulating the catalase activity with 3-AT. However, a rod-like Cu-MOF with 3-AT served as a ligand was obtained by the hydrothermal method without using template. In contrast to Cu-MOF, pH-responsive MAF was chosen as the carrier for targeted drug delivery due to its higher drug load of 17.6% and relatively uniform size, where doxorubicin (DOX) as a model drug was loaded in its cavity and hyaluronic acid (HA) was coated on its surface via electrostatic interactions (denoted as HA-MAF@DOX). In vitro experiments demonstrated that HA-MAF@DOX had high transport efficiency of DOX, effective regulation of catalase (CAT) activity and enhanced cytotoxicity to HepG2 cells. This work is the first use of enzyme inhibitors as ligands to construct functional MOFs via template ligand replacement for effective regulating enzyme activity, mediating intracellular redox homeostasis and enhancing CDT efficacy, which provides a feasible strategy for the construction the functional MOFs in cancer therapy.

Most fracturing treatments today require injecting solid proppants to keep hydraulic fractures open. However, traditional proppants have disadvantages such as causing the reduced propped-fracture volume and abrasion to the pumping equipments and tubulars. To solve these problems, a new self-generating solid proppant has been developed through liquid-solid transition of self-propping fracturing fluid under reservoir conditions. To select the best self-generating solid proppant and compare it with conventional ones, physical property and fracture conductivity tests were done. Experimental results show that two self-generating solid proppants, including S101 and S505, are firstly selected because of their low density, high strength and excellent fracture conductivity. The apparent density is 1.09 g/cm3 for S101 and 1.10 g/cm3 for S505. The crushing rate of S101 is 1.47% while that of S505 is 1.29%. These data illustrate physical properties of self-generating solid proppant are obviously better than those of conventional proppants. Under the same conditions, the larger the spherical particle size of S101 and S505, the higher the fracture conductivity. Non-uniform distribution of proppant pack can increase fracture conductivity. Fracture conductivities of S101 and S505 are higher than that of quartz sand, and even higher than that of ceramsite at low closure stresses. Based on the experimental results, the pumping rate and injecting proportion of self-propping fracturing fluid can be optimized during the fracturing process.

The combination of chemodynamic therapy (CDT) and chemotherapy is a promising strategy to achieve enhanced anticancer effects. Metal-organic frameworks (MOFs), as multifunctional drug delivery vehicles, have received extensive attention in the biomedical field. Carbohydrate has excellent biocompatibility and targeting ability, which can be used as a targeting ligand due to a specific recognition with glycoprotein receptors that overexpress on cancer cell membranes. Herein, the pH-responsive mannose-modified ferrocene MOFs with rare earth metal were synthesized via coordination-driven self-assembly of 1,1'-Ferrocenedicarboxylic acid and ytterbium chloride. Subsequently, DOX@Fc-MOFs-Mann nanoparticles (NPs) were obtained by loading doxorubicin (DOX) and modifying mannose (Mann), where DOX@Fc-MOFs-Mann NPs were able to precisely target HepG2 cells via mannose receptor and slowly decompose in the acidic environment of tumor to release ferrocene, DOX, and Yb

Chitosan oligosaccharides (COS) have the ability to improve plant resistance to pests and diseases through activating plant immune system. However, it remains unclear whether stimulating reason of COS was associated with the plasma membrane proteins. Here, the interaction of COS with wheat leaf cell demonstrated that fluorescence-labeled COS were enriched on the cell surface and the interaction of COS with plasma membrane proteins was confirmed by quartz crystal microbalance (QCM) biosensor. What's more, HPLC and SDS-PAGE analysis showed that COS binding proteins exhibited more than three peaks and the molecular weight were 66 kDa to 97 kDa, where the COS binding proteins were fished out from wheat plasma membrane proteins by the COS affinity column. More importantly, LC-MS/MS analysis demonstrated that several candidates, including W5G2U8_WHEAT (a potential wall-associated receptor kinase protein), W5HY42_WHEAT and W5I0R4_WHEAT (potential G-type lectin S-receptor-like serine/threonine-protein kinase), have the potential to be COS receptors.

A novel approach for fabricating branched-chain (BC) carbohydrate chips to study carbohydrate-protein interactions using Quartz Crystal Microbalance (QCM) biosensor was developed. This approach utilizes functional alkynyl-branch molecule modified chip surfaces, which through the terminal alkynyl group for covalent linking of unprotected azide-carbohydrates. The unprotected azide-carbohydrates were syhthesized in one-step using 2-azido-1,3-dimethyl-imidazolinium as catalyst, avoiding complex chemical modifications. Additionally, the branch surface modified with the carbohydrates not only supplies more specific binding site but also reveals significant cluster effect. To exemplify the sugar cluster effect on BC carbohydrate chips, BC Galactose and Mannose chips prepared in this work were used to determine carbohydrate-lectin interactions using QCM biosensor. The results clearly showed that BC chip significantly improves the detection sensitivity compared with the straight-chain (SC) chip. More importantly, the BC galactose chip sensitivity was enhanced 40% compared with the SC galactose chip.

Carrier-free multifunctional nano photosensitizers (NPSs) based on amphiphilic small molecules with a single photoactivable motif that combine targeted delivery, tumor microenvironment (TME) responsive release, and dual phototherapy with a single irradiation hold great potential to enhance efficacy, safety, and accuracy of cancer treatment as well as facilitate clinical translation. However, the fabrication of such NPSs is challenging. Herein, we report the synthesis of an amphiphilic small glycosylated BODIPY (BSL) molecule with the ability of self-assembly into NPS (BSL NPS). BSL NPS shows excellent biocompatibility, targetability to HepG2 cells via overexpressed galactose receptors on the cell membrane, and responsiveness to high level of glutathione (GSH) in TME. BODIPY released from intracellular BSL NPS by GSH generated reactive oxygen species and hyperthermia upon irradiation of 685 nm NIR laser resulted in significant enhanced cytotoxicity through the synergy of photodynamic and photothermal therapies. More importantly, in vivo experiments with BSL NPS using HepG2 tumor-bearing nude mice model demonstrated good biosafety, enrichment at tumors, and effective destruction of tumors. This work provides a good example of constructing carrier-free multifunctional NPSs based on one single glycosylated amphiphilic small molecule for dual phototherapy against cancers, which may eventually contribute to bridging the translational gap to the clinic.

The antibiotic administration is critical for treating open fracture, especially for tainted bone caused by contamination and the implant. Localized delivery of antibiotics is preferred since it provides elevated antibiotic concentrations at the aiming infection site without systemic toxicity. In this study, a polymer-based composite film with high drug loading capacity and excellent controlled release behavior that can be potentially applied as antibiotics-carrying implants is proposed. First, vancomycin hydrochloride (VH) loaded polyvinyl alcohol-borax (PVA-B) microgels were deposited on the surface of Ti metal straight bone plate by an electrospray technique, porous polyvinyl butyral (PVB) fiber felts were then covered onto the surface of the VH@PVA-B films using electrospinning technique in order to prohibit the free diffusion of VH molecules. The density and size of the pores in the fiber felts can be readily adjusted by exposing the fiber felts to the saturated ethanol vapor, which further controlling the release behavior of the VH molecules from the VH@PVA-B/PVB systems. Importantly, the results showed that our VH@PVA-B/PVB systems with different release behaviors adjustable by the density and size of the pores are all effective to kill S. aureus, as the released VH concentration from the investigated systems are all well above the minimum effective concentration. This study provides a universal strategy to fabricate therapeutic drugs-loaded coatings on implants with the ability to control drug release behaviors.

A convenient approach to regioselective benzylation of carbohydrate trans -diols was developed, where 0.1 equiv. of Bu 2 SnCl 2 and 0.1 equiv. of TBABr were used as the catalysts and 2.0 equiv. of BnCl was used as the benzylation reagent. In most cases, similar or better benzylation regioselectivities and isolated yields were obtained by using catalytic amounts of Bu 2 SnCl 2 , rather than stoichiometric amounts of organotin reagents required.

A two-dimensional (2D) and a three-dimensional (3D) His-tag capture surfaces were fabricated for oriented and reversible immobilization of His-tagged proteins on quartz crystal microbalance (QCM) biosensor surfaces, which can be used for label-free and real-time detection of the interactions between His-tagged protein and its interacting protein (analyte). His-tagged proteins immobilized on the 2D His-tag capture surface maintained a higher binding activity than those immobilized on a 2D carboxyl surface via amine coupling. The 3D His-tag capture surface has about twice the amount of immobilization capacity as the 2D His-tag capture surface, which enables a higher sensitivity for detection. His-tag capture surface can be optionally regenerated to remove the His-tagged protein as well as the analyte for the next cycle of His-tagged protein immobilization, or to only selectively remove the analyte, leaving the His-tagged protein on the surface for the next cycle of analyte binding. Furthermore, the kinetic and affinity studies of the interactions between the His-tagged protein and its interacting protein were performed. This study provides an efficient way to study protein–protein interactions by oriented and reversible immobilization of His-tagged proteins on QCM biosensor surfaces.

Mussel-inspired polydopamine (PDA) has been widely applied for functionalizing various material surfaces through a simple and versatile approach. Several studies have demonstrated the adhesion-promotion properties of the PDA surface for adherent cells. However, few reports are associated with suspension cells. In this study, the attachment property of suspension cells on the PDA surface was investigated for the first time, where we found that the suspension cells can be directly attached to the PDA coating without any secondary modifications. To exemplify the potential of this property, a PDA-based suspension-cell QCM biosensor was fabricated. The biosensor showed a high degree of repeatability and stability as well as low nonspecific binding to the irrelevant protein. The real-time and label-free evaluation of the binding of a diverse range of lectins on three different types of suspension cells indicated the variation of the glycosylation on these cell surfaces. Furthermore, the kinetic evaluation of the protein-carbohydrate interactions on the suspension cell surface was also performed. This work reports a new strategy for fabrication of PDA-based suspension-cell QCM biosensor via simple and efficient immobilization of suspension cells, which provides a simple way for the study of the complex molecular recognition on suspension cell surfaces.

Ultraviolet (UV) B is hazardous to human, plants and animals. With the rapid growth of ozone holes over the earth, the exploration of optical materials that can cut off harmful UV radiation is important. In this work, fusiform TiO2 nanoparticles were synthesized by a hydrothermal synthesis method. The thin films assembled with TiO2 nanoparticles and oppositely charged polyelectrolytes were fabricated via a layer-by-layer assembly method. The fabrication of poly(ethylene imine) (PEI)/TiO2 multilayer films was verified by ultraviolet–visible spectra measurements, scanning electron microscopy and atomic force microscopy. The as-prepared PEI/TiO2 multilayer films can effectively absorb harmful UVB light and filter off visible light. Most importantly, the PEI/TiO2 films can be deposited directly on various kinds of hydrophilic substrates such as quartz, glass, silicon and hydrophobic substrates such as polystyrene, polypropylene, polyethylene and polymethyl methacrylate when the hydrophilic substrates were modified to obtain a hydrophilic surface.

In order to facilitate the determination of the primary and secondary origin of atmospheric organic aerosols, a novel method involving chiral capillary gas chromatography coupled with mass spectrometry has been developed and validated. The method was focused on the analysis of 2-methylerythritol and 2-methylthreitol, considered to be tracers of secondary organic aerosols from the oxidation of atmospheric isoprene. The method was validated by performing various tests using authentic standards, including pure enantiomeric standards. The result showed that the analytical method itself does not affect the enantiomeric composition of the samples analyzed. The method was applied on atmospheric aerosols from a boreal forest collected in Aspvreten, Sweden and on laboratory samples obtained from liquid phase oxidation of isoprene and smog chamber experiments. Aerosol samples contained one enantiomer of 2-methylerythritol in significantly larger quantities than the others. In contrast, the liquid-phase oxidation of isoprene and its gas-phase oxidation in the smog chamber produced all enantiomers in equal quantities. The results obtained where the enantiomer fraction, EF, is larger than 0.50 suggest that 2-methyltetrols in atmospheric aerosols may also have biological origin. Information about the differences between enantiomer fractions obtained using this method brings new insights in the area of atmospheric aerosols.

Amide formation between ring opened aziridines and 2-(diphenylphosphino)benzoic acid provides an easy access to chelating di- and triphosphines with C2 and C3 symmetry.