TARTARIC ACID TEMPLATED SYNTHESIS OF MESOPOROUS Ti-INCORPORATED SILICA AND ITS CATALYTIC ACTIVITY FOR THE RING-OPENING POLYMERIZATION OF ε-CAPROLACTONE

Ti-incorporated mesoporous silica materials with pore diameters of 3-4 nm have been prepared via the co-hydrolysis and co-condensation reactions, that is the sol-gel reactions, of titanium (IV) tetrabutoxide and tetraethylorthosilicate in the presence of tartaric acid as template, followed by extraction with ethanol to remove the templatemolecules. The materials were characterized in detail by Fourier transform infrared spectroscopy, nitrogen adsorption-desorption test, powder X-ray diffraction, transmission electron microscopy and X-ray energy dispersive spectroscopy. Theresults indicate that the Ti-containing silica materials have large specific surface areas (ca. 1200 m^2 g^(-1)) and pore volumes(ca. 0.900 cm^3 g^(-1)). The mesoporosity arises from disordered interconnecting channels or pores. The Ti-incorporated silicasexhibit catalytic activity for the ring-opening polymerization of ε-caprolactone, otherwise, the pure mesoporous silicamaterial shows no catalytic activity under the identical conditions.

Nitric Oxide-Releasing Poly(L-glutamic acid)Hybrid Hydrogels for Accelerating Diabetic Wound Healing

Comprehensive Summary,Diabetic wound healing is threatening worldwide and challenging in wound dressings.Aiming to inhibit heavy inflammation and bacterial infection in diabetic wounds,herein,we facilely construct a kind of NO-releasing poly(L-glutamic acid)(PGA)based graphene oxide(GO)hybrid hydrogel of HDGS at a lower solid percentage,presenting large microporous size of about 20μm,mild photothermal conversion property,and good biocompatibility.Besides improving hemostasis performance,the less amount of GO endowed the hydrogel with near infrared(NIR)responsivity to control fast and pulsatile NO release for killing bacteria and inhibiting heavy inflammation to proheal diabetic wound,in which a broad spectrum of antibacterial activities toward killing S.aureus,E.coli and MRSA was achieved via a combined effect of photothermia and NO release.In vivo effective hemostasis was attained in a rat liver bleeding model with short hemostatic time of~20 s and lower blood loss of 1.5%—2.0%.Moreover,the treatment of HDGS plus 4 times of mild NIR irradiation(10 min,808 nm,1 W/cm^(2)per time)performed superior full diabetic wound healing within 11—14 d,in which the regenerated skins were characteristic of thick epidermis/dermis,dense blood vessels,some hair follicles-embedding,and high level of collagens.

Marine heatwaves in the Gulf of Mexico 1983‒2021: Statistics, recent intensifications, and threats on coral reefs

There is the current lack of comprehensive understanding of the hotspots,frequency,duration,spatiotemporal trends,and physical drivers of marine heatwaves(MHWs)within the Gulf of Mexico(GoM).Here,a series of high-resolution satellite and reanalysis products are used to examine their spatiotemporal characteristics,trends,and possible geophysical triggers of MHWs.Possible impacts of the MHW on coral reefs are also discussed.Results reveal an increasing trend in their frequency,duration,and intensities from 1983–2021,particularly after 2016.It identifies MHWs hotspots within the GoM,notably the northern and western shelves and the Loop Current.The study further documents an intense MHW event from late 2020 to early 2021 near the Yucatan Channel,south of 24°N,attributing its development to oceanic processes such as wind anomalies,anticyclonic eddies,and current-driven heat transport anomalies.The occurrence of this MHW event potentially increased thermal stress on the Campeche and Tuxtlas Reef Systems.This research illuminates the increasing trends and impacts of MHWs in the GoM,providing valuable insights for understanding and predicting the effects of climate change on marine ecosystems.

One-pot photoreduction to prepare NIR-absorbing plasmonic gold nanoparticles tethered by amphiphilic polypeptide copolymer for synergistic photothermal-chemotherapy

We developed one-pot photoreduction strategy to prepare near infrared light(NIR)-absorbing plasmonic gold nanoparticles(Au NPs) tethered by amphiphilic polypeptide copolymer poly(L-cysteine)-b-poly(ethylene oxide)(PLC-b-PEO). The PLC-b-PEO@Au NPs possessed strong NIR absorption at 700–1100 nm and ultrahigh photothermal conversion efficiency of 62.1%. Upon the NIR irradiation(808nm,2 W/cm^2,5 min), the PLC-b-PEO@Au NPs(1mg/mL) sharply attained an elevation of 30.8℃ and the hyperthermia effect could efficiently kill cancer cells in vitro. As for the PT-CT treatment, the doxorubicin(DOX)-loaded nanoparticles of DOX-PLC-b-PEO@Au NPs gave a combination index of 0.9 compared to single chemotherapy(CT) or photothermal therapy(PT), demonstrating a synergistic effect.

A Glycosylated and Catechol-crosslinkedε-Polylysine Hydrogel:Simple Preparation and Excellent Wound Hemostasis and Healing Properties

Commercial tissue adhesives have been widely applied in wound hemostats and dressings while enhancing the hemostasis and healing capabilities is challenging to meet clinical needs.Herein,we designed the glucose-and catechol-functionalized derivatives from commercialε-polylysine(EPL)and prepared the hydrogels by simple amidation and catechol-crosslinking reactions,which have larger swelling ratios of 220%–240%,suitable microporous size of about 6–8µm,and tissue adhesion strength of about 20–40 kPa.The hemolysis,cytotoxicity,and cellular double-staining assays indicate that those hydrogels had good biocompatibility and the H-3 hydrogel with higher glucose content gave a lower hemolysis ratio of 0.73%±0.14%.The blood-clotting index,blood cell attachment and adhesion studies showed those hydrogels had fast blood-coagulation,resulting in excellent hemostasis performance with a short hemostatic time of 38–46 s and less blood loss of 19%–34%in a liver hemorrhage model.A full-thickness rat-skin defect model further demonstrates that the H-3 hydrogel achieved fast wound healing with a wound closure of 70.0%±2.7%on postoperative day 7 and nearly full closure on day 14.Remarkably,the hydroproline level that denotes the collagen production reached a higher one of 7.24±0.55µg/mg comparable to that in normal skins on day 14,evidencing the wound healing was close to completion in the H-3 treatment.Consequently,this work provides a simple method to construct a glycosylated and catechol-functionalized hydrogel platform from commercial EPL,holding translational potentials in wound hemostats and dressings.

Hyperbranched polylysine:Synthesis,mechanism and preparation for NIR-absorbing gold nanoparticles

The ring-opening polymerization (ROP) of N-(tetrafluoroboran ammonium)-L-lysine-N-carboxyanhydride (NH3BF4-Lys NCA) was initiated by triethylamine to prepare hyperbranched polylysine (HPlys) fluoroborate with narrow polydispersity at a low temperature. Both mass spectroscopy analysis and DFT computation evidenced that the resultant cyclic dimer mainly initiated ROP as a secondary species according to normal amine mechanism. The hyperbranched polylysine in aqueous solution existed in a unimolecular state at low concentrations, but transformed into spherical micellar aggregates at a high concentration of 5 mg/mL, as characterized by dynamic laser scattering and transmission electron microscopy. By utilizing multivalent coordination interactions between hyperbranched polylysine and gold, the plasmonic gold nanoparticles (HPlys@Au NPs) were successfully prepared in aqueous solution, which elevated the solution by 23.1℃ upon 5 min of NIR laser irradiation (808 nm, 2 W/cm2).

Quadruple thermo-photo-redox-responsive random copolypeptide nanogel and hydrogel

A series of random copolypeptides of poly（methoxy-diethylene glycol–L-glutamate）-co-poly（S-（onitrobenzyl）-L-cysteine）was synthesized by ring-open copolymerization of methoxydiethylene glycol-Lglutamate-N-carboxyanhydride（EG2-Glu-NCA） and S-（o-nitrobenzyl）-L-cysteine-N-carboxyanhydride（NBC-NCA） in dried dimethylformamide solution, which presents quadruple thermo-photo-redox responsive self-assembly behavior and forms the related nanogel and hydrogel in water.

Sugar-dependent targeting and immune adjuvant effects of hyperbranched glycosylated polypeptide nanoparticles for ovalbumin delivery

Sugar-dependent targeting and immune adjuvant effects of hyperbranched glycosylated polypeptide nanoparticles were disclosed for ovalbumin(OVA)delivery system.The mannose-coated polypeptide nanoparticles can induce strongest targeting and immune adjuvant effects to macrophages than those glucose/lactose-coated ones,which effectively transported OVA into cells and facilitated OVA subcellular escape from endolysosomes into cytoplasm with the assistance of UV irradiation or intracellular acidic pH.

Effect of chirality on conformation and cellular uptake of poly(S-(o-nitrobenzyl)-L,D-cysteine) polypeptides

A series of poly（S-（o-nitrobenzyl）-L,D-cysteine） polypeptides with different chirality was synthesized and their molecular structures,secondary conformations,drug release and biological properties were thoroughly investigated.The chirality of the polypeptides had effect on secondary conformations and the cellular uptake behavior of the related nanoparticles.