Polyvinylidene fluoride (PVDF) membrane is frequently employed for filtration due to its excellent properties. The hydrophobicity of PVDF membrane causes easy fouling; therefore, hydrophilic polymer materials are required to increase hydrophilicity. This study applies cellulose and cellulose esters as fillers for PVDF membranes to solve the fouling problem. Cellulose esters, such as cellulose acetate (PSCA), cellulose benzoate (PSCB), and cellulose citrate (PSCC), were successfully synthesized from peanut shell cellulose (PSC) using Fischer and non-Fischer reactions. The phase inversion method was successfully used to fabricate PVDF membranes with cellulose or cellulose esters as fillers. The fabricated membranes have been applied for methylene blue (MB) filtration. Adding PSC fillers improved the hydrophilicity and performance of the PVDF membranes up to 23.49 ± 2.40 L m−2 h−1 for water flux and 95.75 ± 0.78 % for rejection of MB. Regarding cellulose esters, cellulose acetate gave the highest value of 77.63 L m−2 h−1 for water flux, and cellulose citrate gave the highest value of 86.88 ± 3.54 % for MB rejection. Hence, cellulose or cellulose esters from peanut shells are suitable fillers for MB filtration in PVDF membranes.
This review aims to explore recent advancements in polymer-grafted materials that have emerged as effective adsorbents for the removal of contaminants from wastewater. The most significant environmental issues affecting public health are the presence of dyes, heavy metals, and metalloids in wastewater discharged by various industries. Unfortunately, traditional techniques for treating wastewater are incapable of removing dyes and heavy metals. Due to enhanced capabilities, larger surface areas, greater stability, adjustable properties, and cost-effectiveness, polymer-grafted nanomaterials (PGNs) have attracted the attention of researchers for water purification. Surface engineering of materials with the use of polymers improves greatly their colloidal stability and pollutant adsorption capacity. This study investigates different parameters such as adsorption capacity, pH, and duration in recently reported papers where polymer-grafted adsorbents are developed. The review concludes by offering an overview of recent advancements in the field and proposing potential avenues for future research on related topics.
This study investigates the Quincke rolling phenomenon of snowman-shaped colloidal particles. These chiral rollers exhibit individual and collective dynamic states that depend upon the population and driving field strength. In addition to the previously identified dynamic states, such as spinning and vortex states, we identify the standing and bounded motion of the particles. The bounded motion involves the confined orbiting of particles around the center of mass due to hydrodynamic interactions at low particle area fractions. Our findings provide valuable insights into the behavior of active systems and the fabrication of active materials, emphasizing emergent order and adaptability as key guiding principles.
Understanding the release behaviour of nanodrugs is a crucial step to better assess and control therapeutic outcomes and unfavourable side effects. Herein, we report a systematic study comparing the release kinetics and thermodynamics of paclitaxel (PTX) from supramolecularly assembled sub-micron particles based on natural macromolecules such as zein, whey, casein, bovine serum albumin (BSA) and conventional stabilizers such as pluronic F-127 (poloxamer 407), and β-cyclodextrin (β-CD) to gain insights into the role of carrier chemistry. For this purpose, nanomedicines with statistically indifferent sizes —in the range of 191.0 ± 0.8 nm (BSA) to 243.3 ± 11.6 nm (zein) were prepared (p > 0.05). The zeta potential values ranged from −3.2 ± 1.1 mV (pluronic F-127) to −17.2 ± 1.8 mV (whey) in phosphate buffered saline. The type of nanocarrier significantly influenced the long-term steady-state plateau of the release, resulting in a cumulative release of 70.3 ± 2.0 % of PTX from casein (the highest) and 46.8 ± 4.7 % of PTX from zein (the lowest). Time-resolved release data were analysed with various kinetical models, encompassing zero-order, first-order, Higuchi, Peppas-Sahlin, and Korsmeyer-Peppas kinetics. The analysis revealed that the Korsmeyer-Peppas model best captured the data. For these nanomedicines, the half-life of the encapsulated drugs was found to be 106.4 ± 31.3 h (zein), 4.7 ± 1.2 h (whey), 10.7 ± 1.8 h (pluronic F-127), 6.4 ± 0.9 h (casein), 10.8 ± 3.2 h (β-CD), and 4.0 ± 1.0 h (BSA). TEM characterization revealed differences in the macromolecular arrangement of the active ingredient within these nanocarriers, in addition to the structural differences among the various encapsulating agents. These differences manifested as variations in the internal nanostructures, leading to the creation of distinct microenvironments that could either facilitate or impede the movement of PTX molecules through the encapsulant matrices. In clinical settings, such fine details of nanocarrier design are important: by choosing the most appropriate nanocarrier (or their mixtures), clinicians can fine-tune drug administration to obtain the intended therapeutic window while mitigating the risk of potential negative reactions.
This study aimed to develop an hydroxypropyl methylcellulose-sorbitol (HPMC-sorbitol) thin film as a targeted drug delivery system for coconut shell liquid smoke (CSLS) to effectively treat oral ulcers. The HPMC-sorbitol thin film containing CSLS was created using solvent-casting methods. The resulting thin film underwent comprehensive analysis for shrinkage rate, weight, thickness, water absorption rate, swelling, dissolution, and disintegration time. The producible HPMC-sorbitol thin film containing CSLS exhibited a thickness of 34.89 ± 0.55 μm and a weight of 307.58 ± 10.76 mg, containing phenol and 13-octadecenoic acids. Notably, its swelling, disintegration, and dissolution times were approximately 5 min faster than the blank film. In vitro testing on BHK21 and 7F2 cells demonstrated the thin film's ability to maintain cell viability. In an in vivo oral ulcer model, the thin film reduced neutrophil recruitment, increased macrophage recruitment, and fostered fibroblast proliferation. The HPMC-sorbitol thin film containing CSLS emerged as an effective and well-tolerated delivery system for oral ulcer treatment. Its controlled release mechanism, precise dosing, and protective covering characteristics contribute to enhanced therapeutic outcomes, positioning it as a promising candidate for further development in oral ulcer treatment to improve human health.
The paper presents a quantum chemical approach for assessment of the thermodynamic parameters of association for alkanes CnH2n+2 (n = 6–14) and polyaromatic hydrocarbons (PAH) of the coronene series as model structures of the graphene surface within the framework of semiempirical methods. The enthalpy, entropy and Gibbs energy of formation and binding for alkanes with PAH were calculated using the PM3 and PM6-DH2 methods. It is shown that an adequate description of the interactions in the regarded complexes requires the use of PM6-DH2 method, since it contains corrections for dispersion interactions and hydrogen bonds. The parallel orientation of the alkane molecule relative to the coronene plane is proved to be more energetically preferable than perpendicular one, which is consistent with experimental data.
Intermolecular C–H/π interactions are revealed to be crucial in the 2D film formation of alkanes on graphene/graphite. While interactions between alkane molecules make a destabilizing contribution due to the implementation of energetically unfavorable types of intermolecular CH/HC interactions. This stipulates a threshold chain length of alkanes capable of film formation on the graphene/graphite surface at standard temperature: 14 and 19 carbon atoms for parallel and perpendicular oriented alkanes, respectively. The obtained threshold values of the alkane chain length, as well as the geometric parameters of their orientation in 2D monolayers on the graphene/graphite surface are consistent with available experimental data.
The present study involved the preparation, characterization, and evaluation of layered double hydroxide (LDH) with the assistance of the algae Spirulina platensis (NiAl-Sp and ZnAl-Sp). These materials were investigated for their potential for selective adsorption of cationic dyes, including rhodamine B, malachite green, and methylene blue. The adsorbents exhibit a significant level of selectivity in their capacity to adsorb malachite green in comparison to other cationic dyes. The next parameter of adsorption was evaluated in malachite green as the selective adsorption of cationic dyes. Based on the Langmuir isotherm model, the calculated maximum adsorption capacities of NiAl-Sp and ZnAl-Sp for malachite green were determined to be 478.190 mg/g (pH = 4, 50 °C for 30 min) and 123.457 mg/g (pH = 4, 30 °C for 30 min), respectively. The main processes of adsorption encompassed not only electrostatic interactions but also hydrogen bonding and π-π interactions involving the dye and the amino, hydroxyl, and carboxyl functional groups derived from Spirulina platensis. Spirulina platensis enhances the functional group of LDH. The findings of this study indicate that the NiAl-Sp and ZnAl-Sp composite demonstrated stability as a sorbent for the adsorption of malachite green. Furthermore, it was observed that this composite could be utilized for up to four adsorption cycles, but there was a noticeable decrease in its adsorption capability over time. The findings revealed that the synthesized composite adsorbents of NiAl-Sp and ZnAl-Sp exhibit high efficacy in the adsorption of malachite green from effluent.