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A novel polyoxometalate (POM)-based organic-inorganic hybrid [C33H24O4]H3PMo12O40, namely, TPPA-PMo12, is prepared via a one-pot hydrothermal reaction between a Keggin POM (H3PMo12O40, PMo12) and a star-like N-donor ligand (tri(4-pyridylphenyl)amine, TPPA). The hybrid polyoxometalate is confirmed by characterization with XRD, FT-IR, TGA, SEM and EDS. It exhibits excellent adsorption performance towards β-lactoglobulin, and thus a solid-phase extraction procedure was established for the efficient and selective isolation of β-lactoglobulin from complex sample matrices. At pH 5.0, an adsorption efficiency of 99.2% is achieved for processing 100 μg mL-1β-lactoglobulin in 1.0 mL aqueous solution with 0.5 mg TPPA-PMo12 as an adsorbent. The adsorption behavior of β-lactoglobulin fits the Langmuir model, corresponding to a theoretical adsorption capacity of 1428 mg g-1. The retained β-lactoglobulin could be readily recovered by rinsing with 0.05 mol L-1 Tris-HCl buffer, facilitating a recovery of 91.5%. The hybrid polyoxometalate was practically applied to the selective isolation of β-lactoglobulin from milk whey, and SDS-PAGE assay results clearly indicate that β-lactoglobulin of high-purity is obtained.Micellar composite hydrogel systems represent a promising class of materials for biomolecule and drug delivery applications. In this work a system combining micellar drug delivery with supramolecular hydrogel assemblies is developed, representing an elegant marriage of aqueous hydrophobic drug delivery and next-generation injectable viscoelastic materials. Novel shear thinning and injectable micellar composite hydrogels were prepared using an amphiphilic ABA-type triblock copolymer consisting of a hydrophilic middle block and cholesterol-functionalized polycarbonates as terminal hydrophobic blocks. Varying the concentration and relative hydrophobic-hydrophilic content of the amphiphilic species conferred the ability to tune the storage moduli of these gels from 200 Pa to 3500 Pa. This tunable system was used to encapsulate drug-loaded polymeric micelles, demonstrating a straightforward and modular approach to developing micellar viscoelastic materials for a variety of applications such as delivery of hydrophobic drugs. These hydrogels were also mixed with cholesterol-containing cationic polycarbonates to render antimicrobial activity and capability for anionic drug delivery. Additionally, small-angle X-ray scattering (SAXS) and electron microscopy (EM) results probed the mesoscale structure of these micellar composite materials, lending molecular level insight into the self-assembly properties of these gels. The antimicrobial composite hydrogels demonstrated strong microbicidal activity against Gram-negative and Gram-positive bacteria, and C. albicans fungus. Amphotericin B (AmB, an antifungal drug)-loaded micelles embedded within the hydrogel demonstrated sustained drug release over 4 days and effective eradication of fungi. Our findings demonstrate that materials of different nature (i.e. small molecule drugs or charged macromolecules) can be physically combined with ABA-type triblock copolymer gelators to form hydrogels for potential pharmaceutical applications.The influence of the polymer length and the valency of guest-modified poly(ethylene glycol) (PEG) on the stability, size tunability and formation dynamics of supramolecular nanoparticles (SNPs) has been studied. SNPs were formed by molecular recognition between multi- and monovalent supramolecular building blocks with host or guest moieties, providing ternary complexes of cucurbit[8]uril, methyl viologen and naphthol (Np). SNP assembly was carried out using monovalent Np-modified oligo(ethylene glycol)s and PEGs with 3 or, on average, 18, 111, or 464 ethylene glycol (EG) repeat units. SNP formation and stoichiometry-controlled size tuning were observed for SNPs prepared with Np-modified PEGs containing between 18 and 464 EG repeat units, whereas no distinct assemblies were formed using the shorter Np-functionalized tri(ethylene glycol). Tentatively, the stabilization of SNPs by monovalent PEGs is partly attributed to dynamic exchange. Use of the divalent Np-functionalized PEG (with 113 EG repeat units) slowed down the SNP assembly dynamics and distinct sizes were only obtained when performing the self-assembly at 40 °C for 12 h.Surface modification with affinity ligands capable of capturing bioactive molecules in situ is a widely used strategy for developing biofunctional materials. However, many bioactive molecules, for example zymogens, exist naturally in a "quiescent" state, and become active only when "triggered" by specific activators. In the present study, in situ activation of a surface-integrated zymogen was achieved by introducing affinity ligands for both the zymogen and its activator. Specifically a dual affinity surface was designed for the integration of plasminogen (Plg) and tissue plasminogen activator (t-PA). This surface was expected to have plasmin-generating and, therefore, fibrinolytic properties. A polyurethane surface was modified with a copolymer of 2-hydroxyethyl methacrylate and 1-adamantan-1-ylmethyl methacrylate poly(HEMA-co-AdaMA). The affinity ligands, ARMAPE peptide (for t-PA) and ε-lysine-containing β-cyclodextrin (β-CD-(Lys)7) (for Plg), were attached in sequence via covalent bonding and host-guest interactions, respectively. The resulting surfaces were shown to have high binding capacities for both t-PA and Plg while resisting nonspecific protein adsorption. Pre-loading with t-PA followed by Plg uptake from plasma generated plasmin and thus endowed the surface with fibrinolytic activity. In general the incorporation of dual affinity ligands to achieve surface-promoted bioactivity is a promising approach for the development of biofunctional materials. The method reported herein for the sequential attachment of plasminogen and t-PA affinity ligands can be extended to systems of multiple ligands generally.Near-infrared (NIR)-emitting nanocrystals have enormous potential as an enabling technology for applications ranging from tunable infrared lasers to biological labels. Mercury chalcogenide NCs are one of the attractive NCs with NIR emission; however, the potential toxicity of Hg restricts their diverse applications. https://www.selleckchem.com/products/memantine-hydrochloride-namenda.html Herein, we synthesized low-toxic, highly luminescent and stable GSH-capped HgS/ZnS core/shell NCs by an aqueous route for the first time. The core/shell structure was characterized by using TEM, XRD and XPS, which provide evidence for the shell growth. After the successful growth of an appropriate ZnS shell around HgS NCs, poorly luminescent HgS NCs converted into ultra-bright HgS/ZnS NCs, substantially increasing photoluminescence quantum yield up to 43.8% at room temperature. The fluorescence peak of HgS/ZnS NCs was successfully tuned in a wide NIR window ranging from 785 nm to 1060 nm with high emission efficiency by controlling the synthetic pH values. Significantly, an in vitro cytotoxicity study clearly demonstrated that the HgS/ZnS NCs exhibited good biocompatibility as evidenced by the cell viability retained above 80% at a dose of HgS/ZnS NCs up to 150 μg mL-1. More importantly, the low-toxic NIR-emitting HgS/ZnS NCs have proved to be an effective fluorescent label in in vitro and in vivo imaging. The penetration depth reached 2 cm in a nude mouse with distinct separation of autofluorescence and NCs' fluorescence, giving excellent contrast at all depths. The novel highly-luminescent NIR-emitting HgS/ZnS NCs open up new possibilities for highly-sensitive, highly spectrally resolved and multicolor imaging in biomedical applications.The design of stimuli-responsive controlled drug delivery systems is a promising approach in cancer therapy, but it is still a major challenge to be capable of optimum therapeutic efficacy. Herein, we have elaborately fabricated Fe3O4@ZnO@mGd2O3Eu (mGd2O3Eu was short for mesoporous Gd2O3Eu) multifunction composite nanoparticles by a simple process, with mesoporous Gd2O3Eu shells as supports to increase the anticancer drug loading and thermally responsive polymer poly[(N-isopropylacrylamide)-co-(methacrylic acid)] (P(NIPAm-co-MAA)) gated mesoporous shells as microwave stimulus gatekeepers. The as-synthesized hybrid nanoparticles show a large accessible pore volume (0.19 cm3 g-1) and a high magnetization saturation value (27.8 emu g-1) for drug loading and targeting. The ZnO shells can effectively absorb and convert microwave to heat upon irradiation with microwaves, as a result of the microwave irradiation P(NIPAm-co-MAA) shrinks to a smaller volume and exposes the pores of the mesoporous luminescent shell, realizing the triggered release of the entrapped etoposide (VP16) drug (under microwave irradiation the VP16 release was about 81.7% within 10 h). In vitro studies show the multifunctional nanocarrier feasibility and advantage for remote-controlled drug release systems.Efficient transfection activity and minimal toxicity are of crucial importance to the development of gene delivery systems for practical applications. In this work, guanidine and Schiff-base linked imidazole dual functionalized poly(glycerol methacrylate) (IGEP) was firstly synthesized. Subsequent investigations revealed that this new biomedical material is capable of sufficiently binding to plasmid DNA (pDNA) and formulating optimal sized 100 nm nanoparticles with positive ζ potentials of 10-30 mV. Biological evaluations demonstrated the strategic use of guanidine resulting in enhanced cellular uptake and nuclear localization activities by virtue of its favorable affinity to the cellular membrane, and Schiff-base linked imidazole resulting in promoted endosomal escape and DNA cargo releasing behaviors, consequently leading to better transfection efficacy compared to PEI25K in the targeted cells. Another noteworthy fact was guanidine and imidazole minimized cytotoxicity, hence, these advantageous features provided substantial information to construct a safe and efficient gene delivery carrier towards practical development.With the development of nanotechnology, nanocomposites have been used as bimodal contrast agents for magnetic resonance (MR) and computed tomography (CT) imaging. We have developed a facile method for the synthesis of iron oxide@bismuth sulfide magnetic core-shell nanocomposites. These bifunctional nanocomposites can be made water-soluble via PEG coating and present strong MRI/CT contrast enhancement. Evaluation of cytotoxicity by MTT assay shows that the nanocomposites have low cytotoxicity. The results illustrate that the nanocomposites have great potential as bimodal imaging agents for MR/CT.A lignin-based copolymer with good biocompability was successfully prepared via atom transfer radical polymerization (ATRP) for efficient gene delivery. Kraft lignin was modified into lignin-based macroinitiators and then poly(glycidyl methacrylate)-co-poly(ethylene glycol)methacrylate (PGMA-PEGMA) side chains were prepared via ATRP grafting onto lignin. Ethanolamine was sequentially functionalized onto lignin-PGMA-PEGMA and a cationic lignin-PGEA-PEGMA copolymer consisting of a lignin core and different-length PGEA-PEGMA side chains was produced. Lignin-PGEA-PEGMA copolymers could efficiently compact pDNA into nanoparticles with sizes ranging from 150 to 250 nm at N/P ratios of 10 or higher. The gene transfection efficiency depends greatly on the mass percentage of PGEA units and the N/P ratio. The lignin-PGEA-PEGMA with 46.9% (mass%) of PGEA units (i.e. LG100) has highest transfection efficiency in comparison with the copolymers with a lower amount of PGEA units. In addition, LG100 has high transfection efficiency under serum conditions, which is comparable to or much higher than PEI control in HEK 293T and Hep G2 cell lines.