RSC Advances

Wang, Ruixin; Yang, Ruining; Ren, Zhuohang; Zhang, Bo; Lu, Qingchuang; Yi, Maojie; Luo, Yanlong

doi: 10.1039/d4ra08062apmid: 39664245

Hildebrand (δT) and Hansen (δD, δP, δH) solubility parameters are important indexes to predict the compatibility of components intuitively. Currently, almost all the experiments only measured the solubility parameters of the pristine graphene. Therefore, there is a lack of quantitative relationship between the surface chemistry of graphene and solubility parameters, resulting in no theoretical guidance for the surface modification of graphene. In this work, three-dimensional Hansen solubility parameters are converted to two-dimensional solubility parameters. Hildebrand and two-dimensional solubility parameters of six functionalized graphene as a function of grafting ratio are calculated by molecular dynamics (MD) simulation. Interestingly, if the functional group is at the edge of graphene, the δT decreases with the increase of the grafting ratio, whereas if the functional group is in the plane of graphene, the δT decreases first and then increases with grafting ratio. Two-dimensional solubility parameters are proved to be a good predictor of the compatibility between functionalized graphene and rubbers. The quantitative relationship between the surface chemistry of graphene and compatibility with rubbers based on two-dimensional solubility parameters is constructed. The optimum grafting ratio corresponding to the best compatibility is given. Finally, the effect of temperature on the compatibility behaviors of graphene/rubber mixtures is elucidated.

Tan, Xiaohong; Yu, Libing; Liao, Xindan; Chen, Chun; Chu, Jian; Xiong, Zhonghua; Xia, Binyuan; Tang, Wei; Li, Xijian; Liu, Yanyan

doi: 10.1039/d4ra06173jpmid: 39664247

Searching for highly selective, efficient, and low-toxicity chelating agents is central to resolving uranium contamination in vivo. Peptides composed of amino acids exhibit very low toxicity for accumulation in the human body and have been proven effective in chelating actinides within the human body. Herein, we report a rationally designed short phosphorylated peptide sequence PP-B, which exhibits high affinity and selectivity for uranyl compared to other trace elements present in the body (such as Na+, K+, Ca2+, Co2+, Fe2+, Fe3+, Mg2+, Mn2+, Zn2+). The association constant for the peptide–uranyl complex is calculated to be 7.3 ×105 M−1. The result of DFT calculation shows that the phosphate group binds strongly to the UO22+ center, potentially accounting for the peptide's strong affinity towards UO22+. The results of in vivo uranyl decorporation assays reveal that PP-B has a much lower toxicity and a much higher decorporation efficiency than that of the clinically approved DTPA. These findings render PP-B a promising candidate for utilization as a novel decorporation agent.

Martínez-Sanmiguel, Juan J.; Zarate-Triviño, Diana; García-García, María Paula; García-Martín, José Miguel; Mayoral, Álvaro; Huttel, Yves; Martínez, Lidia; Cholula-Díaz, Jorge L.

doi: 10.1039/d4ra06227bpmid: 39664251

Breast cancer poses a global threat with rising incidence and high mortality. Conventional treatments, including chemotherapy, radiation, surgery, and immunotherapy, have side effects, such as resistance issues and adverse effects due to genetic mutations. Meanwhile, noble metal nanoparticles (NPs) synthesized using environmentally friendly methods offer alternative treatments. Bimetallic gold (Au) and silver (Ag) NPs, using natural compounds like starch as stabilizers, enhance biomedical applications, including breast cancer therapies. In this work, the optical properties, stability, and particle size of colloidal bimetallic Ag/Au NPs were analyzed using UV-visible spectroscopy and ζ-potential measurements. The structural properties of the NPs were studied by powder X-ray diffraction (PXRD), while the morphology, chemical composition and particle size were determined using scanning transmission electron microscopy (STEM). The antitumor properties of the Ag/Au NPs were analyzed on human breast cancer cells (MCF-7) using the MTT viability method, reactive oxygen species (ROS) production, and genotoxicity assays. Peripheral blood mononuclear cells (PBMCs) were used as a reference of healthy cells. UV-vis spectroscopy and EDX mapping analysis confirmed the synthesis of bimetallic Ag/Au NPs. Localized surface plasmon resonance (LSPR) absorption bands shifted from 407 nm (Ag) to 524 nm (Au) based on the chemical composition of the NPs. The Ag/Au NPs showed cytocompatibility in PBMCs and a dose-dependent anticancer effect against MCF-7 cancer cells, as well as cell death dependent on ROS production was observed, particularly in NPs with atomic compositions of 50 and 75 at% Ag. This biological activity of the bimetallic NPs was associated with genotoxic damage of 20–24% greater than that observed in the monometallic counterparts. This study demonstrated the synthesis of mono- and bimetallic Ag/Au NPs using a rapid, reproducible and environmentally friendly method, with successful biomedical application against human breast cancer MCF-7 cells.

Alunni Cardinali, Martina; Casagrande Pierantoni, Debora; Comez, Lucia; Conti, Angela; Chiesa, Irene; De Maria, Carmelo; Cortopassi, Stefania; Caporali, Maria; Paciaroni, Alessandro; Libera, Valeria; Cardinali, Gianluigi; Sassi, Paola; Valentini, Luca

doi: 10.1039/d4ra05126bpmid: 39664243

The ability of fungi and bacteria to form biofilms on surfaces poses a serious threat to health and a problem in industrial settings. In this work, we investigated how the surface stiffness of silk fibroin (SF) films is modulated by the interaction with black phosphorus (BP) flakes, quantifying the morphogenesis of C. albicans cells. Raman and infrared (IR) spectroscopies, along with scanning transmission electron microscopy, allowed us to quantify the thickness and diameter of BP flakes dispersed in the SF matrix (e.g., 5.5 nm in thickness and 20 μm in diameter), as well as an increase in beta-sheet secondary structures, resulting in the mesoscopic formation of a globular and nanofibrous surface. The formation of β-sheet crystals in the SF/BP film was correlated with a higher surface stiffness, influencing the shape of C. albicans cells and suppressing their filamentous growth. Raman spectroscopy analysis ultimately suggests an overall reduction in cell vitality and filmogenic capability of cells grown on fibroin-based films containing BP. Our results suggest that the conformational properties of SF can be suitably tuned to design optimized bioselective coatings for biomedical applications.

Khaoula, Chaoui; Zaari, Halima; Benyoussef, Abdelilah; El Kenz, Abdellah; Loulidi, Mohammed; Moatassim, Hajar; Boujnah, Mourad; Espinosa-Faller, Francisco Javier; Caballero-Briones, Felipe

doi: 10.1039/d4ra08172bpmid: 39664254

CdS(Se)/graphene oxide (GO) heterostructures have received significant attention due to their potential application in optoelectronic devices with tunable bandgap, efficient charge transfer, and enhanced photocatalytic and photovoltaic activity. In this work, Density Functional Theory (DFT) calculations of the photocatalytic properties of CdS(Se)/GO heterostructures were performed. The results of work function, band gap, optical absorption, and band edges of CdS and CdSe in the (001) and (110) directions on graphene oxide are presented. Various approaches to simulate graphene oxide with a different concentration of oxygen, and their subsequent integration into CdS (Se)-GO heterostructures are discussed. DFT calculations were employed to determine the equilibrium value and adhesion energy for various compositions of layers at the interface, as well as different stacking arrangements between graphene oxide and CdS slabs. The results revealed that some oxygen atoms migrate to the CdS matrix and form bonds with Cd atoms. It was observed that the semiconductor band gap can be controlled by the oxidation degree in graphene oxide, and the electronic properties of CdS(Se) depend on the semiconductor orientation and slab number. Notably, surface states are found to be responsible for the negative part of the dielectric function at low frequencies, significantly influencing the electronic properties and charge transfer dynamics. The results show that both structures form type II heterostructures, which is promising for photocatalytic hydrogen generation.

Mughal, Waqas; Ji, Pei; Rauf, Usman; Junping, Liu; Waheed, Abdul; Kumar, Perdeep

doi: 10.1039/d4ra07816kpmid: 39664239

This study aimed to develop an efficient HHO generator with higher gas production, enhanced electrodes, and stable current density. For HHO generator stack fabrication, 15 plates of 304L stainless steel were utilized, accompanied with a 4 mm rubber separator to maintain the gap between electrodes. Each plate in the stack was connected via a separate wire through lug spot welding, enabling the assembly of different configurations for testing. The study introduced three distinct configurations: in the first configuration, no neutral plate was used between the electrodes; the second incorporated one neutral plate; and the third configuration utilized six neutral plates between the cathode and anode. These configurations were tested at 2, 4, and 6 g per L KOH concentrations. In addition, the HHO generator was tested using the pulse width modulation (PWM) approach to adjust voltages at different levels. According to the results, Configuration-2 produced the most significant amount of oxyhydrogen gas with KOH concentrations of 4 and 6 g L−1. Further examination showed that the gas production was unstable when the generator operated continuously for 10 hours, displaying a consistent decrease over time. However, when tested at 2 g L−1 concentration, the yield was slightly lower but more stable. Additionally, it was observed that in Configuration 1, applying higher voltage and current to each cell in the stack led to the formation of iron oxide, resulting in a significant 43% drop in current density in the first 10 hours, which reached 65% after 10 days. In this study, a mathematical model was developed to predict the electric conductivity of the prepared aqueous electrolytic solution of KOH at different temperatures, along with a mathematical model for predicting HHO gas production at different voltages, KOH concentrations and electrode arrangements.

Lee, Ji Ha; Kanda, Wataru; Tachibana, Tomoyuki; Kim, Minhye; Jung, Sung Ho; Kawasaki, Riku; Yabuki, Akihiro

doi: 10.1039/d4ra06787hpmid: 39664250

This study investigates the potential of calix[4]arene-based supramolecular gels for use in drug delivery systems, focusing on both their rheological properties and controlled drug release behavior. We explore how key factors, including temperature, solvent exchange, and UV exposure, influence the gel's mechanical strength and its ability to encapsulate and release drugs. Specifically, our work examines how these external stimuli affect the stability of the gel matrix and modulate the release rate of the encapsulated drug. By systematically evaluating the effects of each factor, we aim to identify conditions that optimize drug release kinetics. The findings offer valuable insights into the development of a tunable, responsive platform for efficient drug delivery, highlighting the potential of calix[4]arene gels as promising candidates for advanced therapeutic applications.

Ayoup, Mohammed Salah; Wahby, Yasmin; Abdel-Hamid, Hamida; Abu-Serie, Marwa M.; Ramadan, Sherif; Barakat, Assem; Teleb, Mohamed; Ismail, Magda M. F.

doi: 10.1039/d4ra90143fpmid: 39664242

Correction for ‘Reinvestigation of Passerini and Ugi scaffolds as multistep apoptotic inducers via dual modulation of caspase 3/7 and P53-MDM2 signaling for halting breast cancer’ by Mohammed Salah Ayoup et al., RSC Adv., 2023, 13, 27722–27737, https://doi.org/10.1039/d3ra04029a.

Zhou, Yujun; Sato, Hitotaka; Kawade, Miwa; Yamagishi, Kenji; Ueno, Yoshihito

doi: 10.1039/d4ra06376gpmid: 39664244

Owing to the increased public interest and advances in chemical modifications, the approval of antisense therapeutics, a class of mRNA-targeting DNA-based oligonucleotide therapeutics, has accelerated in recent years. It was previously reported that siRNAs with several 4′-C-α-aminoethoxy-2′-O-methyl-uridine (4AEoU) analogs could maintain moderate thermal stability similar to the native ones while showing robust nuclease stability. In this study, we further expanded the application of 4AEo modification to antisense therapeutics and achieved superior thermal stability by adding the uracil 5-propynyl modification. Antisense oligonucleotides containing 4′-C-α-aminoethoxy-2′-O-methyl-5-propynyl-uridine (4AEopU) could efficiently activate RNase H-mediated antisense in vitro in the presence of native DNA gaps. These results encourage future studies of 4AEopU-containing antisense therapeutics.

Xu, Mingjin; Xu, Youyin; Du, Chenxi; Gu, Guanghui; Wei, Gang

doi: 10.1039/d4ra07435apmid: 39664248

The flexible design and unique physical and chemical properties of self-assembled peptides have shown great potential for applications in the fields of materials science, life science, and environmental science. Peptide nanofibers (PNFs), as a kind of bioactive nanomaterials, possess excellent biocompatibility, flexible designability, and multifaceted functionalizability. In this work, we design and describe PNFs that self-assembled by peptide molecules as carriers for bimetallic nanosheets (BMNS), leading to the development of hybrid nanomaterials, BMNS–PNFs, with unique properties. The BMNS–PNFs exhibit a photothermal conversion efficiency (PCE) of up to 31.57%, and can be used as a potential nanoplatform for photothermal therapy (PTT) of lung tumour cells. Through the results, it is shown that the PNFs can reduce the cytotoxicity of BMNS–PNFs and that BMNS–PNFs have excellent cancer cell killing effects, with photothermal killing rates of more than 95% and 90% for lung cancer cells HCC2279 and PC9, respectively. Finally, the comprehensive PTT performance of BMNS–PNFs is analysed by Ranking of Efficiency Performance (REP), and the REP value of BMNS–PNFs is calculated to be 0.741. The peptide sequences used to assemble into PNFs in this study are instructive for functional design and structural modulation of molecular self-assembly, and the constructed bimetallic–biomolecular hybrid materials provide a potential strategy for medical bioengineering.