Transdermal drug delivery is a new means of delivering drugs through the skin to achieve therapeutic effects. Microneedles have several advantages, including low cost, easy self-administration, and high delivery efficiency. Different polymers affect the morphology, mechanical properties, and drug delivery efficiency of microneedles. To study the performance and limitations of microneedles (MNs), we prepared different ratios of polymers. MNs were fabricated from polyvinylpyrrolidone (PVP) and sodium carboxymethyl cellulose (CMC-Na) using the centrifugal molding method. Needle morphology, formability, and other properties of the polymers were evaluated to compare the performances of MNs with different ratios. PVP and CMC-Na were intermixed at different ratios with water as the solvent. The soluble MNs were prepared by mold casting. The morphology, thermodynamic properties, and crystallinity were studied using scanning electron microscopy (SEM), thermogravimetric analysis (TG), differential scanning calorimetric analysis (DSC), and X-ray diffraction (XRD). The results showed that composite microneedles have good thermal stability. Among the different compositions tested, the 10% PVP/2% CMC-Na composite microneedle demonstrated the best performance with a regular surface morphology and relatively high thermal decomposition and melting temperatures. These results indicate that microneedles with appropriate ratios of two different materials possess good formability and other properties.

The ongoing challenge of water pollution necessitates innovative approaches to remove organic contaminants from wastewater. In this work, new two-dimensional S-scheme heterojunction photocatalysts Bi₂O₃/CdS and MoS₂/Bi₂O₃/CdS that are intended for the effective photocatalytic destruction of 4-nitrophenol, a dangerous organic pollutant, are synthesized and characterized. Utilizing a solvothermal method, successfully generated these ternary nanocomposites, which were characterized through various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), high resolution transmission electronmicroscopy (HRTEM), Brunauer-Emmett-Telle (BET) and diffuse reflectance spectroscopy (DRS). Our results demonstrated that the Bi₂O₃/CdS heterojunction achieved an 86% degradation rate of 4-nitrophenol, while the MoS₂/Bi₂O₃/CdS composite exhibited exceptional photocatalytic performance, achieving nearly complete degradation (99%) within 120 min under visible light irradiation. Most importantly the improved photocatalytic activity of MoS₂/Bi₂O₃/CdS heterojunction originated from the release of internal electric field in S-scheme heterojunction. This enhanced activity is attributable to the synergistic effects of the heterojunctions that facilitate more effective charge separation and generation with more OP and RP confirmed the composite synthesis using S-scheme. The S-scheme is further confirmed by XPS, DRS, XPS-VB and photocurrent response. These findings highlight the promising application of these advanced photocatalysts in real-world wastewater treatment processes, offering a sustainable solution to combat water pollution.

Currently, organic dyes and other environmental contaminants are focal areas of research, with considerable interest in the production of stable, high-efficiency, and eco-friendly photocatalysts to eliminate these contaminants. In the present work, bismuth-doped zinc ferrite (Bi-ZnFe₂O₄) nanoparticles (NPs) and bismuth-doped zinc ferrites supported on sulfur-doped graphitic carbon nitride (Bi-ZnFe₂O₄/S-g-C₃N₄) (BZFG) photocatalysts were synthesized via a hydrothermal process. SEM, XRD, and FTIR techniques were used to examine the morphological, structural, and bonding characteristics of the synthesized photocatalysts. The photocatalytic competence of the functional BZFG nanocomposites (NCs) was studied against MB under sunlight. The influence of Bi (0.5, 1, 3, 5, 7, 9, and 11 wt.%) doping on the photocatalytic performance of ZnFe₂O₄ was verified, and the 9%Bi-ZnFe₂O₄ nanoparticles exhibited the maximum MB degradation. Then, 9%Bi-ZnFe₂O₄ NPs were homogenized with varying amounts of S-g-C₃N₄ (10, 30, 50, 60, and 70 wt.%) to further enhance the photocatalytic performance of BZFG NCs. The fabricated Bi-ZnFe₂O₄/30%S-g-C₃N₄ (BZFG-30) composite outperformed ZnFe₂O₄, S-g-C₃N₄ and other BZFG NCs in terms of photocatalytic performance. The enriched photocatalytic performance of the BZFG NCs might be ascribed to a more efficient transfer and separation of photo-induced charges due to synergic effects at the Bi-ZnFe₂O₄/S-g-C₃N₄ interconnection. The proposed modification of ZnFe₂O₄ using Bi and S-g-C₃N₄ is effective, inexpensive, and environmentally safe.

A multi-stimuli responsive fluorophore, named NBDNI, was developed by constructing a 1,8-naphthalimide derivative in which a rotatable electron-donating N,N-dimethylaniline group attached to its 4-position. This molecular structure endowed NBDNI with aggregate-induced emission (AIE) and twisted intramolecular charge transfer (TICT) properties, enabling remarkable fluorescence changes in response to multiple external stimuli: (i) sensitivity to polarity in various solvent systems and polymer matrix; (ii) significant fluorescence response and excellent linearity towards temperature changes in solution; (iii) distinct switch of fluorescence color upon acid and base treatments; (iv) reversible mechanochromism behavior in the solid state. Moreover, the mechanisms underlying the aforementioned stimuli-responsive phenomena have been proposed based on comprehensive systematic measurements. Furthermore, preliminary applications such as fluorescence thermometry and acid/base test paper have been demonstrated. This research will bring about new opportunities for the development of novel stimuli-responsive luminescent materials.

There has been a lot of interest in the manufacture of stable, high-efficiency photocatalysts. In this study, initially Cr doped ZnFe₂O₄ nanoparticles (NPs) were made via surfactant-assisted hydrothermal technique. Then Cr-ZnFe₂O₄ NPs were modified by incorporating S-g-C₃N₄ to enhance their photocatalytic efficiency. The morphological, structural, and bonding aspects were analyzed by XRD, FTIR, and SEM techniques. The photocatalytic efficiency of the functional Cr-ZnFe₂O₄/S-g-C₃N₄ (ZFG) heterostructure photocatalysts was examined against MB under sunlight. The produced ZFG-50 composite has the best photocatalytic performance, which is 2.4 and 3.5 times better than that of ZnFe₂O₄ and S-g-C₃N₄, respectively. Experiments revealed that the enhanced photocatalytic activity of the ZFG nanocomposite was caused by a more effective transfer and separation of photo-induced charges. The ZFG photocatalyst can use sunlight for treating polluted water, and the proposed modification of ZnFe₂O₄ using Cr and S-g-C₃N₄ is efficient, affordable, and environmentally benign. Under visible light, Gram-positive and Gram-negative bacteria were employed to ZFG-50 NCs’ antimicrobial activity. These ZFG-50 NCs also exhibit excellent antibacterial potential.

The addition of 0.5 wt.% of DMTMSP to the electrolyte could improve the low-temperature discharge and cycling performances of high voltage layered lithium cobaltate-based lithium ion batteries.