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1.
Front Med (Lausanne) ; 11: 1406578, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39301492

RESUMO

Objective: To evaluate the efficacy of intraocular lens (IOL) cushion plate technology in reducing corneal endothelial cell loss during hard-core cataract surgery compared with conventional ultrasonic emulsification. Methods: Seventy-six patients with hard-core cataracts who underwent surgery at our institution from April 2019 to June 2022 were included. The patients were divided into an observation group (IOL cushion plate technology, 38 patients) and a control group (conventional ultrasonic emulsification, 38 patients). Surgical outcomes, including the corneal endothelial cell loss rate, best corrected visual acuity (BCVA), and central corneal thickness (CCTc), were compared between the two groups. Results: Preoperative patient characteristics were similar between the groups. Postoperatively, both groups demonstrated similar BCVA and CCTc values on days 7 and 30. However, compared with the observation group, the control group presented a significantly greater rate of corneal endothelial cell loss on postoperative days 7 and 30 (p < 0.05). Intraoperative complications and postoperative complications were notably greater in the control group (p < 0.05). The observation group had reduced ultramilk time and total energy consumption (p < 0.05). Conclusion: IOL cushion plate technology offers advantages in preserving corneal endothelial cells during hard-core cataract surgery, potentially improving surgical safety and efficacy.

2.
Int J Biol Macromol ; 278(Pt 3): 134930, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39179068

RESUMO

Hollow carbon spheres (HCSs) have attracted broad attention in aqueous zinc-ion hybrid supercapacitors (ZIHSCs) owing to their distinctive properties. However, traditional methods for fabricating HCSs face limitations, including complex multistep procedures, the use of corrosive chemicals, and stringent reaction conditions. In this work, biomass-based poly(γ-glutamic acid)/Ni2+/melamine/chitosan nanoparticles were used as the precursors to fabricate N/O co-doped hollow graphite carbon spheres (HGCSs). Thanks to the appropriate hydrophilic characteristic, specific surface area, pore size distribution, and electrical conductivity, the fabricated HGCSs cathode exhibited superior electrochemical properties. The assembled HGCSs-based ZIHSCs device showed a satisfactory specific capacitance of 133.2 mAh·g-1 at a current density of 1.0 A·g-1, high energy densities of 75.2 Wh·kg-1 at 10,000 W·kg-1 and 107.9 Wh·kg-1 at 1000 W·kg-1, respectively. Additionally, the assembled HGCSs-based ZIHSCs device displayed an exceptional cycling stability, enduring up to 10,000 cycles at 0.5 A·g-1 with a capacity retention rate of 98.1 %. This work provides a facile and novel strategy to prepare superior electrochemical performance biomass-based HGCSs cathode for ZIHSCs.


Assuntos
Quitosana , Grafite , Nanopartículas , Ácido Poliglutâmico , Zinco , Grafite/química , Ácido Poliglutâmico/química , Ácido Poliglutâmico/análogos & derivados , Quitosana/química , Nanopartículas/química , Zinco/química , Níquel/química , Capacitância Elétrica , Carbono/química , Eletrodos , Nitrogênio/química , Água/química , Porosidade
3.
Int J Biol Macromol ; 266(Pt 1): 130940, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521331

RESUMO

In recent years, functional foods with lipophilic nutraceutical ingredients are gaining more and more attention because of its potential healthy and commercial value, and developing of various bioderived food-grade particles for use in fabrication of Pickering emulsion has attracted great attentions. Herein, the bio-originated sodium caseinate-lysozyme (Cas-Lyz) complex particles were firstly designed to be used as a novel interfacial emulsifier for Pickering emulsions. Pickering emulsions of various food oils were all successfully stabilized by the Cas-Lyz particles without addition of any synthetic surfactants, while the fluorescence microscopy and SEM characterizations clearly evidenced Cas-Lyz particles were attached on the surface of emulsion droplets. Additionally, the Cas-Lyz particles stabilized emulsion can also be used to encapsulate the ß-carotene-loaded soybean oil, suggestion a potential method to carry lipophilic bioactive ingredients in an aqueous formulation for food, cosmetic and medical industry. At last, we present a Pickering emulsion strategy that utilizes biocompatible, edible and body temperature-responsive lard oil as the core material in microcapsules, which can achieve hermetic sealing and physiological temperature-triggered release of model nutraceutical ingredient (ß-carotene).


Assuntos
Cápsulas , Emulsões , Temperatura , beta Caroteno , beta Caroteno/química , Emulsões/química , Liberação Controlada de Fármacos , Caseínas/química
4.
ACS Appl Mater Interfaces ; 16(8): 10126-10137, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38349949

RESUMO

Considering the superiorities of abundance, easy collection, low cost, and nearly constant composition, the wasted A4 papers are deemed as a recyclable and scalable carbon source to fabricate functional carbon materials for Zn-ion hybrid supercapacitors (ZIHSCs), which integrate the supercapacitors' high-power output and batteries' high energy density. Herein, the wasted A4 papers are efficiently converted into an advanced carbon material owning a hierarchical porous structure with a high surface area and interconnected multiscale channels, a graphitic structure, and a good level of N/O codoping. By taking advantage of these features, an express electron/ion transfer pathway, a large accessible surface interface, and a robust architecture are achieved for swift kinetics, numerous active sites, and excellent steadiness to afford a charming Zn2+ storage capability for the aqueous coin-type ZIHSC device (a high capacity of 244 mAh g-1 at 0.1 A g-1 with a capacity conservation of 116.4 mAh g-1 even amplifying the current density by 200 times, a supreme energy density of 190.4 Wh kg-1, a supreme power output of 18 kW kg-1, and an eminent durability of 93.8% over 10,000 cycles at 10 A g-1). Excitingly, the quasi-solid ZIHSC device also bespeaks an enjoyable capacity of 211.7 mAh g-1, a high energy density of 159.3 Wh kg-1, good mechanical flexibility, and a low self-discharge rate. This work puts forward a simple and scalable strategy to enable the wasted A4 paper as a competitive carbon source to construct advanced cathode material for Zn2+ storage.

5.
Int J Biol Macromol ; 231: 123157, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36649867

RESUMO

Tiny crosslink in chitosan (CS)/poly-(γ-glutamic acid) (γ-PGA) hydrogel leads to some disadvantages including low mechanical strength and high swelling. To enhance the crosslink of CS/γ-PGA hydrogel, amino acid (AA) was introduced to remove the drawbacks. The results indicated that AA can dramatically increase the crosslink and mechanical properties of CS/γ-PGA hydrogel, and AA chain length and concentration have a drastic effect on them. Particularly, 0.5 % ß-Alanine (ß-Ala) decreased the hydrogel by 70 % in porosity, 52 % in water solubility, and 30 % in swelling, but increased by 2.2-fold in elastic modulus, 2.08-fold in stress, and 1.53-fold in water retention. The porosity of the hydrogel correlates positively with the elastic modulus but negatively with the crosslinking degree. The effect of pH on CS/ß-Ala/γ-PGA hydrogel was investigated in the load and release of benzalkonium chlorides (BAC). ß-Ala strengthened pH response of the hydrogel in BAC load and release. The loading capacity increased with pH value, and 0.5 % ß-Ala increased the hydrogel by 1.25-fold in the release capacity in alkaline environment, suggesting a good buffering effect of ß-Ala on pH variation to accelerate the transportation of BAC. CS/ß-Ala/γ-PGA hydrogel will be competently applied as a potential material for wound dressing in alkaline environment.


Assuntos
Quitosana , Hidrogéis , Hidrogéis/química , Quitosana/química , Ácido Glutâmico , Bandagens , beta-Alanina , Ácido Poliglutâmico/química , Água
6.
Polymers (Basel) ; 14(10)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35631951

RESUMO

Hydrogels have been widespreadly used in various fields. But weak toughness has limited their further applications. In this study, Dendrobium officinale enzyme (DOE) was explored to improve chitosan/γ-poly(glutamic acid) (CS/γ-PGA) hydrogel in the structure and properties. The results indicated that DOE with various sizes of ingredients can make multiple noncovalent crosslinks with the skeleton network of CS/γ-PGA, significantly changing the self-assembly of CS/γ-PGA/DOE hydrogel to form regular protuberance nanostructures, which exhibits stronger toughness and better behaviors for skin care. Particularly, 4% DOE enhanced the toughness of CS/γ-PGA/DOE hydrogel, increasing it by 116%. Meanwhile, water absorption, antioxygenation, antibacterial behavior and air permeability were increased by 39%, 97%, 27% and 52%.

7.
Langmuir ; 36(51): 15543-15551, 2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33332125

RESUMO

The transition between a novel oil-in-dispersion emulsion and an oil-in-water (O/W) Pickering emulsion triggered by pH was achieved using alumina nanoparticles in combination with a cationic surfactant. In acidic and neutral aqueous media, positively charged particles and the surfactant both at very low concentrations costabilize an oil-in-dispersion emulsion with the surfactant adsorbed at droplet interfaces and particles dispersed in the aqueous phase between the droplets. In alkaline media, however, particles become negatively charged and are hydrophobized in situ by adsorption of the surfactant to become surface-active and stabilize an O/W Pickering emulsion. The transition between the two is also possible by lowering the pH. The transformation can be achieved several times in a mixture of 0.1 wt % nanoparticles and 0.01 mM surfactant. This transition is significant, since particles can be made to either adsorb at the oil-water interface, which is beneficial for applications like biphasic catalysis, or remain dispersed in the aqueous phase, which is favorable for their recovery and reuse.

8.
Langmuir ; 35(11): 4058-4067, 2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30807183

RESUMO

A novel CO2/N2 switchable n-decane-in-water emulsion was prepared, which is stabilized by a CO2/N2 switchable surfactant [ N'-dodecyl- N, N-dimethylacetamidine (DDMA)] in cationic form in combination with positively charged alumina nanoparticles at concentrations as low as 0.01 mM and 0.001 wt %, respectively. The particles do not adsorb at the oil-water interface but remain dispersed in the aqueous phase between surfactant-coated droplets. A critical zeta potential of the particles of ca. +18 mV is necessary for the stabilization of the novel emulsions, suggesting that the electrical double-layer repulsions between particles and between particles and oil droplets are responsible for their stability. By bubbling N2 into the emulsions, demulsification occurs following transformation of DDMA molecules from the surface-active cationic form to the surface-inactive neutral form and desorption from the oil-water interface. Bubbling CO2 into the demulsified mixtures, cationic DDMA molecules are re-formed, which adsorb to the droplet interfaces, ensuring stable emulsions after homogenization. Compared with Pickering emulsions and traditional emulsions, the amount of switchable surfactant and number of like-charged particles required for stabilization are significantly reduced, which is economically and environmentally benign for practical applications.

9.
Angew Chem Int Ed Engl ; 57(26): 7738-7742, 2018 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-29693309

RESUMO

Novel oil-in-water (O/W) emulsions are prepared which are stabilised by a cationic surfactant in combination with similarly charged alumina nanoparticles at concentrations as low as 10-5 m and 10-4  wt %, respectively. The surfactant molecules adsorb at the oil-water interface to reduce the interfacial tension and endow droplets with charge ensuring electrical repulsion between them, whereas the charged particles are dispersed in the aqueous films between droplets retaining thick lamellae, reducing water drainage and hindering flocculation and coalescence of droplets. This stabilization mechanism is universal as it occurs with different oils (alkanes, aromatic hydrocarbons and triglycerides) and in mixtures of anionic surfactant and negatively charged nanoparticles. Further, such emulsions can be switched between stable and unstable by addition of an equimolar amount of oppositely charged surfactant which forms ion pairs with the original surfactant destroying the repulsion between droplets.

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