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881.
A bio-inspired drug carrier was developed by dual functionalization of chitosan using L-glutamic acid (GA) and phyto-synthesized zinc oxide nanoparticles (ZNPs). A highly porous, three-dimensional network of nanocomposite hydrogel (GA-CHGZ) was obtained upon cross-linking chitosan using biomass-derived dialdehyde cellulose. The hydrogel was optimally loaded with naringenin (NRG) and further characterized using nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and swelling studies. An enhanced NRG loading efficiency of 85.23% was obtained using functionalized hydrogel compared to 52.54% using non-functionalized hydrogel. Delivery studies displayed a maximum release of 69.63% for 1.0 mg/ml of initial NRG concentration at pH 5, which is a highly preferred condition for cancer therapeutics. While ZNPs’ embedment was instrumental in improving the NRG loading and delivery rates, the GA conjugation increased the stability of NRG in the GA-CHGZ, aiding sustained NRG release, which followed a non-Fickian diffusion mechanism with polymer swelling. Antimicrobial potential was explored against Staphylococcus aureus and Trichophyton rubrum strains. The biocompatibility assay using L929 normal cells showed enhanced cell proliferation characteristics for the materials, revealing significant cell viability. The anticancer activity of NRG tested against A431 human skin carcinoma cells increased up to nine-fold with a reduced IC50 value when a functionalized hydrogel was used instead of pure NRG without the nanocomposite carrier. Thus, the bio-functionalized drug–carrier system has a promising application for wound healing and topical skin cancer therapies.  相似文献   
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Capacitive deionization (CDI) is an emerging electrochemical-based adsorption system that has a high capability for the water reclamation with future potential towards an energy-efficient and cost-effective technique for industrial implementations. However, the higher cost of electrodes and poor performance limit its scale-up, and there is a need to focus on a cost-effective electrode towards economic impacts. Among the various waste resources, plastic sources would be the better precursor for carbonization as the plastic-derived carbon possess enhanced surface properties and high electrochemical stability. Further, the carbonization of plastic products towards electrode minimizes greenhouse gas emissions, maintains environmental sustainability and achieves a dual benefit of circular economy with water reclamation. This paper highlights the overview of CDI, the significance of electrodes in CDI for electrosorption studies, various synthetic routes of plastic-derived carbon, and its properties that help the researchers to focus on zero waste discharge-based CDI process.  相似文献   
884.
A convenient synthesis of a broad series of thirteen examples of alkyne-spacer derivatives 2 from the well-known Sonogashira cross-coupling reaction on diazenyl-pyrazolo[1,5-a]pyrimidin-2-amine compounds 1 is reported. The reactivity of heterocycles 1 due the presence of selected electron-donor (EDG) and electron-withdrawing (EWG) groups attached to different alkynes was evaluated. Also, the reactional versatility due the position variation of the bromo atom at the scaffolds 1 was also investigated. In general, derivatives presented strong absorption bands at the 250–500 nm optical window and UV to cyan emission properties. Also, the redox analysis was recorded by electrochemical cyclic voltammetry technique. For HSA biomacromolecule assays, spectroscopic studies by UV-Vis, steady-state and time-resolved emission fluorescence, and molecular docking calculations evidenced the ability of each compound to establish interactions with human serum albumin (HSA). Finally, the behavior presented for this new class of heterocycles makes them a promising tool as optical sensors for albumins.  相似文献   
885.
The advent of new solid-state energy storage devices to tackle the electrical revolution requires the usage of nonlinear behavior leading to emergent phenomena. The ferroelectric analyzed herein belongs to a family of electrolytes that allow energy harvesting and storage as part of its self-charging features when thermally activated. The Na2.99Ba0.005ClO electrolyte shows quasi-adiabatic behavior with a continuous increase in polarization upon cycling, displaying almost no hysteresis. The maximum polarization obtained at a weak electric field is giant and similar to the remanent polarization. It depends on the temperature with a pyroelectric coefficient of 5.37 C m−2 °C−1 from −5 to 46 °C. The emergence occurs via negative resistance and capacitance. The glass transition is found to have its origins in the sharp depolarization at 46 – 48 °C. Above –10 °C, at ≈ –5 °C, another thermal anomaly may rely on the topologic characteristics of the A3–2xBaxClO (A = Li, Na, K) glass electrolytes enabling positive feedback of the current of electrons throughout the surface of the inner cell. The phenomena may pave the way toward a better understanding of dipolar nanodomain fragile glasses with exceptional ferroelectric characteristics to architect energy harvesting and storage devices based on multivalent thermally activated Na+-ion-ion electrolytes.  相似文献   
886.
Surface engineering of metal–organic framework nanoparticles (MOF NPs), and enabling their post-synthetic modulation that facilitates the formation of bio-interfaces has tremendous potential for diverse applications including therapeutics, imaging, biosensing, and drug-delivery systems. Despite the progress in MOF NPs synthesis, colloidal stability and homogeneous dispersity—a desirable property for biotechnological applications, stands as a critical obstacle and remains a challenging task. In this report, dynamic surfaces modification of MOF NPs with polyethylene glycol (PEG) polymer is described using grafting-from PEGylation by employing nitroxide-mediated polymerization (NMP) and inserting arginylglycylaspartic acid (RGD) peptides on the surface via a nitroxide exchange reaction (NER). The dynamic modification strategy enables tailoring PEG-grafted MOF NPs of the type UiO-66-NH2 with improved colloidal stability, and high dispersity, while the morphology and lattice crystallinity are strictly preserved. The interaction of PEG-grafted MOF NPs with human serum albumin (HSA) protein under physiological conditions is studied. The PEG-grafted colloidal MOF NPs adsorb less HSA protein than the uncoated ones. Therefore, the described approach increases the scope of bio-relevant applications of colloidal MOF NPs by reducing nonspecific interactions using NMP based PEGylation, while preserving the possibility to introduce targeting moieties via NER for specific interactions.  相似文献   
887.
Protein mutations alter protein–protein interactions that can lead to a number of illnesses. Mutations in lamin A (LMNA) have been reported to cause laminopathies. However, the proteins associated with the LMNA mutation have mostly remained unexplored. Herein, a new chemical tool for proximal proteomics is reported, developed by a combination of proximity chemical tagging and a bio-orthogonal supramolecular latching based on cucurbit[7]uril (CB[7])-based host–guest interactions. As this host–guest interaction acts as a noncovalent clickable motif that can be unclicked on-demand, this new chemical tool is exploited for reliable detection of the proximal proteins of LMNA and its mutant that causes laminopathic dilated cardiomyopathy (DCM). Most importantly, a comparison study reveals, for the first time, mutant-dependent alteration in LMNA proteomic environments, which allows to identify putative laminopathic DCM-linked proteins including FOXJ3 and CELF2. This study demonstrates the feasibility of this chemical tool for reliable proximal proteomics, and its immense potential as a new research platform for discovering biomarkers associated with protein mutation-linked diseases.  相似文献   
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Silicon - Silicon (Si) acts to reduce biotic and abiotic stresses in plants. Herein, we aimed to assess the impact of an amorphous silica-based fertilizer (ASF) applied to soil on the yield,...  相似文献   
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