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Journal of Materials Chemistry. B Jul 2024Topical treatment of vitreoretinal diseases remains a challenge due to slow corneal uptake and systemic clearance. Exosomes are emerging nanocarriers for drug delivery...
Topical treatment of vitreoretinal diseases remains a challenge due to slow corneal uptake and systemic clearance. Exosomes are emerging nanocarriers for drug delivery due to biocompatibility and cellular targeting properties. To apply them for retinal targeting the topical route, exosomes must traverse various ocular barriers including the cornea, lens, vitreous humor (VH), and the retina itself. Here we engineered high-purity milk-derived exosomes by anchoring arginine-rich cationic motifs PEG lipid insertion on their surface. Modification enabled exosomes to use weak-reversible electrostatic interactions with anionic glycosaminoglycan (GAG) and water content of the tissue to enhance their transport rate and retention. Addition of cationic motifs neutralized the anionic surface charge of exosomes (-24 to -2 mV) without impacting size or morphology. Cationic-motif-modified exosomes exhibited two-fold faster steady state diffusivity through bovine corneas compared to unmodified exosomes. Fluorescence recovery after photobleaching confirmed that cationic-motif-modified exosomes can diffuse through VH without steric hindrance. In healthy VH, cationic-motif-modified exosomes demonstrated stronger binding resulting in three-fold lower average diffusivity that enhanced by six-fold in 50% GAG-depleted VH recapitulating advanced liquefaction. Cationic-motif-modified exosomes penetrated through the full-thickness of porcine retinal explants resulting in ten-fold higher uptake in photoreceptors and three-fold greater transfection with encapsulated eGFP mRNA compared to unmodified exosomes. Cationic-motif-modified exosomes are safe to use as they did not adversely affect the mechanical swelling properties of the cornea or lens nor impact retinal cell viability. Cationic-motif-modified exosomes, therefore, offer themselves as a cell-free nanocarrier platform for gene delivery to retinal photoreceptors potentially the topical route.
PubMed: 38946491
DOI: 10.1039/d4tb00849a -
Chemical Communications (Cambridge,... Jul 2024Here we report stepwise methylation of end-on bridging dinitrogen to a hydrazido ligand to a pentamethylhydrazinium salt, which is mediated by a titanium system with a...
Here we report stepwise methylation of end-on bridging dinitrogen to a hydrazido ligand to a pentamethylhydrazinium salt, which is mediated by a titanium system with a tripodal aryloxide supporting ligand. The results constitute a synthetic cycle for pentamethylhydrazinium formation from dinitrogen and methyl iodide. We also describe silylation of the dinitrogen complex and carboxylation of the hydrazido complex.
PubMed: 38946396
DOI: 10.1039/d4cc02080d -
Inorganic Chemistry Jul 2024The first fully inorganic Pt(IV) carbonato-complex -[Pt(CO)(OH)] with a {PtO} coordination sphere was isolated as the (MeN)[Pt(CO)(OH)] () salt. The compound was...
The first fully inorganic Pt(IV) carbonato-complex -[Pt(CO)(OH)] with a {PtO} coordination sphere was isolated as the (MeN)[Pt(CO)(OH)] () salt. The compound was characterized using single-crystal and powder X-ray diffraction, Raman spectroscopy, infrared spectroscopy (FTIR), electrospray ionization mass spectrometry (ESI-MS), nuclear magnetic resonance spectroscopy (NMR), and thermogravimetric analysis (TG). Density functional theory (DFT) calculations were also performed to analyze the spectral features of the complex. crystallizes in the triclinic system (P-1) with a Z of 1. The -[Pt(CO)(OH)] anion has axial hydroxo ligands and κ-CO ligands, which form an equatorial plane. This anionic complex exhibits notable stability in aqueous solutions, while the axial hydroxo ligand can be readily modified, as exemplified by the acylation of the -[Pt(CO)(OH)] into -[Pt(CO)(OAc)] anion. Furthermore, it has been shown that rigid and glittering platinum coatings can be electrochemically deposited from an aqueous solution of without the addition of surfactants.
PubMed: 38946343
DOI: 10.1021/acs.inorgchem.4c00909 -
Langmuir : the ACS Journal of Surfaces... Jun 2024An atmospheric pressure plasma jet (APPJ) is used to process electrochemically deposited NiFe on carbon paper (NiFe/CP). The reactive oxygen and nitrogen species (RONs)...
Direct Current Pulse Atmospheric Pressure Plasma Jet Treatment on Electrochemically Deposited NiFe/Carbon Paper and Its Potential Application in an Anion-Exchange Membrane Water Electrolyzer.
An atmospheric pressure plasma jet (APPJ) is used to process electrochemically deposited NiFe on carbon paper (NiFe/CP). The reactive oxygen and nitrogen species (RONs) of the APPJ modify the surface properties, chemical bonding types, and oxidation states of the material at the self-sustained temperature of the APPJ. The APPJ treatment further enhances the hydrophilicity and creates a higher disorder level in the carbon material. Moreover, the metal carbide bonds of NiFe/CP formed in the electrochemical deposition (ED) process are converted to metal oxide bonds after APPJ processing. The potential application of APPJ treatment on NiFe/CP in alkaline water electrolysis is demonstrated. With more oxygen-containing species and better hydrophilicity after APPJ treatment, APPJ-treated NiFe/CP is applied as the electrocatalyst for the oxygen evolution reaction (OER) in alkaline water electrolysis. APPJ-treated NiFe/CP is also used in a custom-made anion-exchange membrane water electrolyzer (AEMWE); this should contribute toward realizing the practical large-scale application of AEM for hydrogen production.
PubMed: 38946167
DOI: 10.1021/acs.langmuir.4c01169 -
Inorganic Chemistry Jun 2024Constructing the plasmonic metal/semiconductor heterostructure with a suitable Schottky barrier height (SBH) and the sufficiently reliable active sites is of importance...
Constructing the plasmonic metal/semiconductor heterostructure with a suitable Schottky barrier height (SBH) and the sufficiently reliable active sites is of importance to achieve highly efficient and selective photocatalytic CO reduction into hydrocarbon fuels. Herein, we report Au/sulfur vacancy-rich ZnInS (Au/VR-ZIS) hierarchical photocatalysts, fabricated via in situ photodepositing Au nanoparticles (NPs) onto the nanosheet self-assembled ZnInS (ZIS) micrometer flowers (MFs) with rich sulfur vacancies (V). Density functional theory (DFT) calculations confirm that for the Au/VR-ZIS system, the Au NPs serve as the reaction sites for HO oxidation, and the VR-ZIS MFs serve as those for CO reduction. The rich V in the Au/VR-ZIS hybrid can reduce its SBH so as to boost more hot electrons in the Au NPs across its Schottky barrier and then inject into the conduction band (CB) of the VR-ZIS MFs. In addition, V can also act as the electron sink to trap the photogenerated electrons, retarding the recombination of photogenerated carriers. The two merits effectively enhance the photogenerated electron density in the surface of VR-ZIS MFs, availing CO photoreduction. In addition, the introduction of rich V in the Au/VR-ZIS hybrid can offer more active sites, benefiting the CO adsorption and accelerating the desorption of CO* from the surface of the photocatalyst. Therefore, under visible light illumination with no sacrificial reagent, the optimum photocatalyst (Au/VR-ZIS-0.4) presents the enhanced and selective CO photoreduction into CO (8.15 μmol gh and near 100%), which are superior to those of most of ZIS-based and plasmon-based photocatalysts. The photocatalytic activity is about 40.0-fold as high as that of the Vs-poor-ZIS (VP-ZIS) MFs. This work contributes a viable strategy for designing highly efficient plasmonic photocatalysts by using the synergism of the anion vacancies and the optimized SBH induced by them.
PubMed: 38946108
DOI: 10.1021/acs.inorgchem.4c02376 -
ACS Applied Materials & Interfaces Jun 2024In this research, a novel MgSiO fiber membrane (MSFM) loaded with indocyanine green (ICG) and doxorubicin (DOX) was prepared. Because of MgSiO's unique lamellar...
In this research, a novel MgSiO fiber membrane (MSFM) loaded with indocyanine green (ICG) and doxorubicin (DOX) was prepared. Because of MgSiO's unique lamellar structure composed of a silicon-oxygen tetrahedron, magnesium ion (Mg) moves easily and can be further replaced with other cations. Therefore, because of the positively charged functional group of ICG, MSFM has a rather high drug loading for ICG. In addition, there is electrostatic attraction between DOX (a cationic drug) and ICG (an anionic drug). Hence, after loading ICG, more DOX can be adsorbed into MSFM because of electrostatic interaction. The ICG endows the MSFM outstanding photothermal therapy (PTT) performance, and DOX as a chemotherapeutic drug can restrain tumor growth. On the one hand, H exchanged with the positively charged DOX based on the MgSiO special lamellar structure. On the other hand, the thermal effect could break the electrostatic interaction between ICG and DOX. Based on the above two points, both tumor acidic microenvironment and photothermal effect can trigger DOX release. What's more, in vitro and in vivo antiosteosarcoma therapy evaluations displayed a superior synergetic PTT-chemotherapy anticancer treatment and excellent biocompatibility of DOX&ICG-MSFM. Finally, the MSFM was proven to greatly promote cell proliferation, differentiation, and bone regeneration performance in vitro and in vivo. Therefore, MSFM provides a creative perspective in the design of multifunctional scaffolds and shows promising applications in controlled drug delivery, antitumor performance, and osteogenesis.
PubMed: 38946103
DOI: 10.1021/acsami.4c05744 -
Geobiology 2024Methane is a potent greenhouse gas that enters the marine system in large quantities at seafloor methane seeps. At a newly discovered seep site off the coast of Point...
Carbonate chimneys at the highly productive point Dume methane seep: Fine-scale mineralogical, geochemical, and microbiological heterogeneity reflects dynamic and long-lived methane-metabolizing habitats.
Methane is a potent greenhouse gas that enters the marine system in large quantities at seafloor methane seeps. At a newly discovered seep site off the coast of Point Dume, CA, ~ meter-scale carbonate chimneys host microbial communities that exhibit the highest methane-oxidizing potential recorded to date. Here, we provide a detailed assessment of chimney geobiology through correlative mineralogical, geochemical, and microbiological studies of seven chimney samples in order to clarify the longevity and heterogeneity of these highly productive systems. U-Th dating indicated that a methane-driven carbonate precipitating system at Point Dume has existed for ~20 Kyr, while millimeter-scale variations in carbon and calcium isotopic values, elemental abundances, and carbonate polymorphs revealed changes in carbon source, precipitation rates, and diagenetic processes throughout the chimneys' lifespan. Microbial community analyses revealed diverse modern communities with prominent anaerobic methanotrophs, sulfate-reducing bacteria, and Anaerolineaceae; communities were more similar within a given chimney wall transect than in similar horizons of distinct structures. The chimneys represent long-lived repositories of methane-oxidizing communities and provide a window into how carbon can be transformed, sequestered, and altered over millennia at the Point Dume methane seep.
Topics: Methane; Carbonates; Bacteria; California; Seawater; Geologic Sediments; Ecosystem; Archaea
PubMed: 38946067
DOI: 10.1111/gbi.12608 -
Journal of Oleo Science 2024The objective of this research was to evaluate the efficiency of aqueous enzymatic extraction (AEE) to obtain oil from hemp seeds (Cannabis sativa L.) grown in northern...
Combined Effect of Protease, Hemicellulase and Pectinase on the Quality of Hemp Seed Oil (Cannabis sativa L.) Obtained by Aqueous Enzymatic Extraction as an Eco-friendly Method.
The objective of this research was to evaluate the efficiency of aqueous enzymatic extraction (AEE) to obtain oil from hemp seeds (Cannabis sativa L.) grown in northern Morocco. Optimisation of AEE extraction parameters, including pH, enzyme concentration (hemicellulase, protease and pectinase), temperature and incubation time, to maximize oil yield was achieved using response surface methodology with a central composite design. For comparison, the solvent extraction (Soxhlet) (SE) method was also used. Optimized hydrolysis conditions involved incubation for 4 hours at 60°C with a pH of 6.5, using a multi-enzyme preparation comprising protease, hemicellulase and pectinase at concentrations of 55, 202.5 and 234 U/mg, respectively. Referring to the conventional Soxhlet extraction (SE), Aqueous Enzymatic Extraction (AEE) achieved a 30.65% oil recovery rate under the optimized parameters mentioned above. The use of enzymes produced an oil that was more stable against oxidation than the solvent-extracted oil, with a peroxide value (PV) of 19.54 and 47.87 meq O /kg, respectively. Furthermore, HPLC-DAD analysis of tocopherol content indicated a higher total tocopherol content (547.2 mg/kg) in Aqueous Enzymatic Extraction (AEE) compared to Soxhlet Extraction (SE) (513.51 mg/kg), with γ-tocopherol being the predominant form. No significant differences in fatty acid composition were observed between the two extraction methods with linoleic acid and alpha-linolenic acid being the predominant constituents.
Topics: Cannabis; Polygalacturonase; Plant Oils; Glycoside Hydrolases; Seeds; Peptide Hydrolases; Hydrolysis; Liquid-Liquid Extraction; Food Quality; Water; Tocopherols; Hydrogen-Ion Concentration; Temperature; Solvents; Green Chemistry Technology
PubMed: 38945925
DOI: 10.5650/jos.ess24031 -
Journal of Oleo Science 2024Handwashing represents an important personal hygiene measure for preventing infection. Herein, we report the persistence of antibacterial and antiviral effects after...
Handwashing represents an important personal hygiene measure for preventing infection. Herein, we report the persistence of antibacterial and antiviral effects after handwashing with fatty acid salt-based hand soap. To this end, we developed a new in vitro test method to measure persistence, utilizing coacervation formed by anionic surfactants and cationic polymers to retain highly effective soap components against each bacterium and virus on the skin. Coacervation with fatty acid salts and poly diallyldimethylammonium chloride (PDADMAC) as a cationic polymer allowed the persistence of antibacterial and antiviral effects against E. coli, S. aureus, and influenza virus even 4 h after handwashing. Furthermore, we confirmed an increase in the number of residual components effective against each bacterium and virus on the skin. In summary, the current findings describe an effective approach for enhancing the protective effects of handwashing.
Topics: Soaps; Escherichia coli; Hand Disinfection; Quaternary Ammonium Compounds; Anti-Bacterial Agents; Staphylococcus aureus; Antiviral Agents; Polyethylenes; Skin; Surface-Active Agents; Humans; Fatty Acids; Time Factors; Orthomyxoviridae
PubMed: 38945924
DOI: 10.5650/jos.ess23266 -
Journal of Oleo Science 2024Eleven kinds of Camellia oleifera seed oils (CSOs) were evaluated in terms of chemical constituents, antioxidant activities, acid value (AV) as well as peroxide value... (Comparative Study)
Comparative Study
Eleven kinds of Camellia oleifera seed oils (CSOs) were evaluated in terms of chemical constituents, antioxidant activities, acid value (AV) as well as peroxide value (POV). These CSOs contained abundant β-sitosterol, squalene, α-tocopherol and phenolics, in which the squalene was the distinct constituent with the content between 45.8±0.8 and 184.1±5.5 mg/kg. The β-sitosterol ranging from 143.7±4.8 to 1704.6±72.0 mg/kg contributed a considerable content to total accompaniments. Palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid were present in these CSOs, in which the dominant fatty acid was oleic acid with the content between 59.66±0.72 and 82.89±2.16 g/100 g. The AV ranged from 0.1±0.0 to 1.3±0.0 mg KOH/g, and the POV was between 0.1±0.0 and 1.0±0.0 g/100 g. These CSOs showed antioxidant activity based on DPPH and ABTS radical scavenging assay. Both α-tocopherol and β-sitosterol contents showed a positive correlation with DPPH and ABTS values, respectively, while the α-tocopherol content showed a negative correlation with AV. These results suggested that CSO can be categorized into high oleic acid vegetable oil with abundant active constituents, of which the quality presented variation among different origins. These accompaniments may contribute to the delay of its quality deterioration.
Topics: Camellia; Antioxidants; Plant Oils; Sitosterols; Seeds; Squalene; China; alpha-Tocopherol; Oleic Acid; Chemical Phenomena; Fatty Acids; Palmitic Acid; Phenols; Linoleic Acid; Peroxides
PubMed: 38945923
DOI: 10.5650/jos.ess23228