RSC Advances

Dhibar, Subhendu; Pal, Suchetana; Karmakar, Kripasindhu; Hafiz, Sk Abdul; Bhattacharjee, Subham; Roy, Arpita; Rahaman, S. K. Mehebub; Ray, Soumya Jyoti; Dam, Somasri; Saha, Bidyut

doi: 10.1039/d3ra05019jpmid: 38025858

A remarkable ultrasonication technique was successfully employed to create two novel metallogels using citric acid as a low molecular weight gelator, in combination with cadmium(ii)-acetate and mercury(ii)-acetate dissolved in N,N-dimethyl formamide at room temperature and under ambient conditions. The mechanical properties of the resulting Cd(ii)- and Hg(ii)–metallogels were rigorously examined through rheological analyses, which revealed their robust mechanical stability under varying angular frequencies and shear strains. Detailed characterization of the chemical constituents within these metallogels was accomplished through EDX mapping experiments, while microstructural features were visualized using field emission scanning electron microscope (FESEM) images. Additionally, FT-IR spectroscopic analysis was employed to elucidate the metallogel formation mechanism. Significantly, the antimicrobial efficacy of these novel metallogels was assessed against a panel of bacteria, including Gram-positive strains such as Bacillus subtilis and Staphylococcus epidermidis, as well as Gram-negative species like Escherichia coli and Pseudomonas aeruginosa. The results demonstrated substantial antibacterial activity, highlighting the potential of Cd(ii) and Hg(ii)-based citric acid-mediated metallogels as effective agents against a broad spectrum of bacteria. In conclusion, this study provides a comprehensive exploration of the synthesis, characterization, and antimicrobial properties of Cd(ii) and Hg(ii)-based citric acid-mediated metallogels, shedding light on their promising applications in combating both Gram-positive and Gram-negative bacterial infections. These findings open up exciting prospects for the development of advanced materials with multifaceted industrial and biomedical uses.

Liu, Shaoqing; Liu, Ruili; Xing, Xia; Yang, Chongqing; Xu, Yi; Wu, Dongqing

doi: 10.1039/d3ra90101gpmid: 38025870

Correction for ‘Highly photoluminescent nitrogen-rich carbon dots from melamine and citric acid for the selective detection of iron(iii) ion’ by Shaoqing Liu et al., RSC Adv., 2016, 6, 31884–31888, https://doi.org/10.1039/C5RA26521E.

Wang, Xiao; Chen, Lijun; Zhang, Chunlai; Zhang, Xiping; Wu, Yintao; Wang, Bo

doi: 10.1039/d3ra05921apmid: 38025861

In experiments, printing paper is imprinted with three different ink micropatterns (square, grid, and stripe). The wetting contact angle of water droplets on a heterogeneous surface is then investigated using a proportionate scaling molecular dynamics (MD) simulation, where the water droplets and the ink-patterned printing paper are both shrunk by a factor of 200 000 collectively. The errors from the theoretical values are always less than 1°, which is much less than the bias of experimental measurement data, according to the modeling contact angles. It has been demonstrated that this proportionate scaling approach works well to appropriately explain the interaction between micro-/nanostructures and liquids.

Tiwari, Ghanshyam; Khanna, Ashish; Mishra, Vinay Kumar; Sagar, Ram

doi: 10.1039/d3ra05986cpmid: 37942237

In recent decades, the utilization of microwave energy has experienced an extraordinary surge, leading to the introduction of innovative and revolutionary applications across various fields of chemistry such as medicinal chemistry, materials science, organic synthesis and heterocyclic chemistry. Herein, we provide a comprehensive literature review on the microwave-assisted organic synthesis of selected heterocycles. We highlight the use of microwave irradiation as an effective method for constructing a diverse range of molecules with high yield and selectivity. We also emphasize the impact of microwave irradiation on the efficient synthesis of N- and O-containing heterocycles that possess bioactive properties, such as anti-cancer, anti-proliferative, and anti-tumor activities. Specific attention is given to the efficient synthesis of pyrazolopyrimidines-, coumarin-, quinoline-, and isatin-based scaffolds, which have been extensively studied for their potential in drug discovery. The article provides valuable insights into the recent synthetic protocols and trends for the development of new drugs using heterocyclic molecules.

Nguyen-Ha, Bao-Ngan; Phan Dang, Cam-Tu; Van Duong, Long; Pham-Ho, My Phuong; Nguyen, Minh Tho; Tam, Nguyen Minh

doi: 10.1039/d3ra06000dpmid: 38025864

The geometric and electronic structures of a small series of mixed gold and platinum AuxPty2+ clusters, with x + y = 10, were investigated using quantum chemical methods. A consistent tetrahedral pyramid structure emerges, displaying two patterns of structural growth by a notable critical point at y = 5. This affects the clusters' electron population, chemical bonding, and stability. For the Pt-doped Au clusters with y values from 2 to 5, the bonds enable Pt atoms to assemble into symmetric line, triangle, quadrangle, and tetragonal pyramidal Pty blocks, respectively. For the Au-doped Pt clusters, with larger values of y > 5, the structures are more relaxed and the d electrons of Pt atoms become delocalized over more centers, leading to lower symmetry structures. A certain aromaticity arising from delocalization of d electrons over the multi-center framework in the doped Pt clusters contributes to their stability, with Pt102+ at y = 10 exhibiting the highest stability. While the ground electronic state of the neutral platinum atom [Xe]. 4f145d96s1 leads to a triplet state (3D3), the total magnetic moments of AuxPty2+ are large increasing steadily from 0 to 10 μB and primarily located on Pt atoms, corresponding to the increase of the number of Pt atoms from 0 to 10 and significantly enhancing the magnetic moments. An admixture of both Au and Pt atoms thus emerges as an elegant way of keeping a small pyramidal structure but bringing in a high and controllable magnetic moment.

Ali, Imtiaz; Ahmad, Maqsood; Ridha, Syahrir; Iferobia, Cajetan Chimezie; Lashari, Najeebullah

doi: 10.1039/d3ra06008jpmid: 38025871

In the context of deep well drilling, the addition of functionalized additives into mud systems becomes imperative due to the adverse impact of elevated borehole temperatures and salts on conventional additives, causing them to compromise their intrinsic functionalities. Numerous biomaterials have undergone modifications and have been evaluated in drilling muds. However, the addition of dually modified tapioca starch in bentonite-free mud systems remains a notable gap within the existing literature. This study aims to examine the performance of dually modified carboxymethyl irradiated tapioca starch (CMITS) under high temperature and salt-containing conditions employing central composite design approach; the study evaluates the modified starch's impact on mud rheology, thermal stability, and salt resistance. The findings indicated that higher DS (0.66) and CMITS concentrations (8 ppb) improved plastic viscosity (PV), yield point (YP) and gel strength (GS), while increased salt and temperature decreased it, demonstrating the complex interplay of these factors on mud rheology. The developed empirical models suggested that DS 0.66 starch addition enhanced rheology, especially at elevated temperatures, demonstrating improved borehole cleaning potential, supported by quadratic model performance indicators in line with American Petroleum Institute (API) ranges. The optimized samples showed a non-Newtonian behavior, and Power-law model fitting yields promising results for improved cuttings transportation with starch additives.

Yahya, Siti Hajjar; Al-Lolage, Firas A.; Mahat, Mohd Muzamir; Ramli, Muhammad Zahir; Syamsul, Mohd; Falina, Shaili; Ahmad Ruzaidi, Dania Adila; Danial, Wan Hazman; Shafiee, Saiful Arifin

doi: 10.1039/d3ra05592bpmid: 38025850

The increasing levels of carbon dioxide (CO2) in the atmosphere may dissolve into the ocean and affect the marine ecosystem. It is crucial to determine the level of dissolved CO2 in the ocean to enable suitable mitigation actions to be carried out. The conventional electrode materials are expensive and susceptible to chloride ion attack. Therefore, there is a need to find suitable alternative materials. This novel study investigates the electrochemical behaviour of dissolved CO2 on roughened molybdenum (Mo) microdisk electrodes, which were mechanically polished using silicon carbide paper. Pits and dents can be seen on the electrode surface as observed using scanning electron microscopy. X-ray diffraction spectra confirm the absence of abrasive materials and the presence of defects on the electrode surface. The electrochemical surface for the roughened electrodes is higher than that for the smoothened electrodes. Our findings show that the roughened electrodes exhibit a significantly higher electrocatalytic activity than the smoothened electrodes for the reduction of dissolved CO2. Our results reveal a linear relationship between the current and square root of scan rate. Furthermore, we demonstrate that saturating the electrolyte solution with CO2 using a bubbling time of just 20 minutes at a flow rate of 5 L min−1 for a 50 mL solution is sufficient. This study provides new insights into the electrochemical behaviour of dissolved CO2 on roughened Mo microdisk electrodes and highlights their potential as a promising material for CO2 reduction and other electrochemical applications. Ultimately, our work contributes to the ongoing efforts to mitigate the effects of climate change and move towards a sustainable future.

El-Shazly, Ayat Nasr; Shalan, Ahmed Esmail; Rashad, Mohamed Mohamed; Abdel-Aal, Elsayed Ali; Ibrahim, Ibrahim Ahmed; El-Shahat, Mohamed F.

doi: 10.1039/d3ra90109bpmid: 38025877

Expression of Concern for ‘Solid-state dye-sensitized solar cells based on Zn1−xSnxO nanocomposite photoanodes’ by Ayat Nasr El-Shazly et al., RSC Adv., 2018,8, 24059–24067, DOI: https://doi.org/10.1039/c8ra02852d.

Niavarani, Zahra; Breite, Daniel; Ulutaş, Berfu; Prager, Andrea; Kantoğlu, Ömer; Abel, Bernd; Gläser, Roger; Schulze, Agnes

doi: 10.1039/d3ra06345cpmid: 38025853

The existence of endocrine disrupting chemicals (EDCs) in water and wastewater gives rise to significant environmental concerns. Conventional treatment approaches demonstrate limited capacity for EDC removal. Thus, incorporation of advanced separation procedures becomes essential to enhance the efficiency of EDC removal. In this work, adsorber composite microfiltration polyethersulfone membranes embedded with divinyl benzene polymer particles were created. These membranes were designed for effectively removing a variety of EDCs from water. The adsorber particles were synthesized using precipitation polymerization. Subsequently, they were integrated into the membrane scaffold through a phase inversion process. The technique of electron beam irradiation was applied for the covalent immobilization of particles within the membrane scaffold. Standard characterization procedures were carried out (i.e., water permeance, contact angle, X-ray photoelectron spectroscopy and scanning electron microscopy) to gain a deep understanding of the synthesized membrane properties. Dynamic adsorption experiments demonstrated the excellent capability of the synthesized composite membranes to effectively remove EDCs from water. Particularly, among the various target molecules examined, testosterone stands out with the most remarkable enhancement, presenting an adsorption loading of 220 mg m−2. This is an impressive 26-fold increase in the adsorption when compared to the performance of the pristine membrane. Similarly, androst-4-ene-3,17-dione exhibited an 18-fold improvement in adsorption capacity in comparison to the pristine membrane. The composite membranes also exhibited significant adsorption capacities for other key compounds, including 17β-estradiol, equilin, and bisphenol-A. With the implementation of an effective regeneration procedure, the composite membranes were put to use for adsorption over three consecutive cycles without any decline in their adsorption capacity.

Davoodi, Mehdi; Davar, Fatemeh; Rezayat, Mohammad R.; Jafari, Mohammad T.; Bazarganipour, Mehdi; Shalan, Ahmed Esmail

doi: 10.1039/d3ra90113kpmid: 38025879

Expression of concern for ‘Synthesis and characterization of a new ZIF-67@MgAl2O4 nanocomposite and its adsorption behaviour’ by Mehdi Davoodi et al., RSC Adv., 2021, 11, 13245–13255, https://doi.org/10.1039/D1RA01056E