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"Mohamed, Omran"
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Review on Natural, Incidental, Bioinspired, and Engineered Nanomaterials: History, Definitions, Classifications, Synthesis, Properties, Market, Toxicities, Risks, and Regulations
Nanomaterials are becoming important materials in several fields and industries thanks to their very reduced size and shape-related features. Scientists think that nanoparticles and nanostructured materials originated during the Big Bang process from meteorites leading to the formation of the universe and Earth. Since 1990, the term nanotechnology became very popular due to advances in imaging technologies that paved the way to specific industrial applications. Currently, nanoparticles and nanostructured materials are synthesized on a large scale and are indispensable for many industries. This fact fosters and supports research in biochemistry, biophysics, and biochemical engineering applications. Recently, nanotechnology has been combined with other sciences to fabricate new forms of nanomaterials that could be used, for instance, for diagnostic tools, drug delivery systems, energy generation/storage, environmental remediation as well as agriculture and food processing. In contrast with traditional materials, specific features can be integrated into nanoparticles, nanostructures, and nanosystems by simply modifying their scale, shape, and composition. This article first summarizes the history of nanomaterials and nanotechnology. Followed by the progress that led to improved synthesis processes to produce different nanoparticles and nanostructures characterized by specific features. The content finally presents various origins and sources of nanomaterials, synthesis strategies, their toxicity, risks, regulations, and self-aggregation.
Journal Article
Liposomal co-delivery of β-carotene and doxorubicin for enhanced colorectal-cancer therapy
Colorectal cancer (CRC) remains a major cause of cancer-related mortality, motivating delivery systems that retain antitumor activity while limiting off-target toxicity. We engineered neutral multilamellar soy-lecithin liposomes co-encapsulating β-carotene (BC) and doxorubicin (DOX). Thin-film hydration produced vesicles with a DLS Z-average of 122.4 ± 83.4 nm (PDI = 0.534) and ζ-potential of − 25.6 ± 8.0 mV, and a TEM diameter of 184 ± 34 nm, with > 90% entrapment efficiency for both cargos. In HCT-116 cells the formulation preserved DOX potency (IC₅₀, µg mL⁻
1
, mean ± SD: free DOX 610.9 ± 11.4; DOX-Lipo 614.0 ± 1.8; BC–DOX-Lipo 618.9 ± 5.8) and remained ~ 1.5-fold more active than BC alone (free BC 960.6 ± 13.6; BC-Lipo 951.8 ± 18.8). Annexin V/PI flow cytometry showed that BC–DOX-Lipo achieved the highest total apoptosis (44.51 ± 4.45%) and deep G₀/G₁ arrest (92.06 ± 9.2%), reducing S-phase to 6.37 ± 0.60% (p = 0.0186 vs DOX-Lipo). Alkaline comet analysis indicated that co-delivery modestly attenuated DOX-associated DNA fragmentation (tailed cells 11.43 ± 0.45% for BC–DOX-Lipo vs 16.27 ± 0.25% for DOX-Lipo, p < 0.001), consistent with BC’s redox buffering. Differential scanning calorimetry and FTIR supported drug–bilayer interactions: BC slightly increased Tm and acyl-chain order, whereas DOX disrupted cooperativity; co-loading shifted T
m
to 37.84 °C and broadened the transition, indicating a more fluid bilayer at 37 °C. In-silico ADMET profiling (contextual, not in-vivo PK) highlighted superior oral absorption and BBB penetration for BC and negligible oral uptake for DOX; docking predicted higher DOX affinities across Bcl-2, β-catenin, P-glycoprotein, and topoisomerase II (e.g., − 9.06 to − 9.30 kcal mol⁻
1
) relative to BC (≈ − 7.6 to − 7.8 kcal mol⁻
1
). Overall, liposomal co-delivery maintains DOX cytotoxicity while strengthening G₁/S checkpoint blockade and increasing programmed cell death, with partial moderation of DNA fragmentation. These in-vitro data motivate stability optimization and in-vivo evaluation in CRC models.
Journal Article
Sequence stratigraphy of the syn-rift miocene succession in the Abu Rudeis-Sidri Field, Gulf of Suez, Egypt
The syn-rift Miocene succession of the Gulf of Suez remains poorly constrained, with persistent uncertainties in rift initiation timing, paleoenvironmental reconstruction, and the interplay between tectonics and eustasy—factors that complicate stratigraphic correlation and hydrocarbon exploration. This study aims to refine the chronostratigraphic framework, reconstruct depositional environments, and develop a detailed sequence stratigraphic model for the Abu Rudeis–Sidri Field in the east-central Gulf of Suez through integration of high-resolution foraminiferal biostratigraphy, wireline logs, and seismic data from four wells (ARM-7, ARS-6, SIDRI-20, SIDRI-9). Planktonic and benthic foraminifera constrain the succession to the early Burdigalian–early Langhian, encompassing the
Globigerinoides altiaperturus–Catapsydrax dissimilis
,
Trilobatus trilobus
, and
Praeorbulina glomerosa
zones. Ten benthic biofacies define paleodepths from inner shelf (< 50 m) to upper slope (> 150 m), enabling reconstruction of depositional environments and relative sea-level trends. Four third-order depositional sequences (SQ1–SQ4) are recognized, bounded by regionally mappable sequence boundaries and maximum flooding surfaces. Stacking patterns reveal deepening from SQ1 to SQ3 followed by shoaling and lagoonal restriction in SQ4. Tectonic subsidence and block tilting exerted primary control on accommodation, whereas eustatic influence is expressed mainly at flooding surfaces. Correlation with regional and global sea-level curves shows partial alignment with Burdigalian–Langhian cycles, underscoring the dominance of local tectonics. This refined framework enhances understanding of syn-rift sedimentation and provides predictive insights for hydrocarbon exploration in rift-related basins.
Journal Article
PEGylated liposomal metformin overcomes pharmacokinetic barriers to trigger potent mitochondrial disruption and cell cycle arrest in hepatocellular carcinoma
This study presents a comprehensive experimental and computational evaluation of PEGylated liposomal metformin as a nanocarrier-based therapeutic strategy for hepatocellular carcinoma (HCC). Liposomal formulations were prepared via thin-film hydration, yielding spherical, well-dispersed vesicles with high encapsulation efficiency (> 90%) and a mean hydrodynamic diameter of 177.2 ± 30.2 nm. PEGylation and metformin loading induced significant physicochemical alterations, as confirmed by differential scanning calorimetry and FTIR spectroscopy, reflecting increased bilayer fluidity and headgroup interactions. Cytotoxicity assays revealed a substantial enhancement in antitumor potency: PEGylated liposomal metformin reduced the IC₅₀ against HepG2 cells to 118.76 μg/mL compared to 2392.81 μg/mL for free metformin—representing a > 20-fold improvement. In Vero cells, IC₅₀ values were 137.13 μg/mL and 2113.86 μg/mL, respectively, yielding a selectivity index of 1.15. Apoptosis analysis demonstrated increased early and late apoptotic populations, with PEGylated formulations inducing total apoptosis rates of 20.67% in HepG2 cells. Cell cycle profiling revealed marked G₀/G₁ arrest, with 78.12% accumulation versus 58.21% in untreated controls. DNA fragmentation analysis via comet assay further supported elevated genotoxic effects in cancer cells. Molecular docking and 100 ns molecular dynamics simulations confirmed stable binding of metformin to mitochondrial Complex I and CDK4/cyclin D3, with a total MM-PBSA binding energy of − 27.33 kcal/mol in the CDK4 complex. These findings demonstrate that PEGylated liposomal encapsulation substantially enhances the cytotoxic profile of metformin, supporting its advancement as a targeted nanotherapeutic candidate for HCC.
Journal Article
A comparative analysis of nanocoated expanded polystyrene for sustainable infrastructure applications
Engineers increasingly face challenges due to the demand for sustainable infrastructure; thus, this research evaluates different road embankment techniques based on sustainability. It compares the environmental impacts and economic feasibility of three road embankment techniques: using traditional soil backfilling, using expanded polystyrene (EPS) geofoam blocks with geomembrane protection, and using EPS blocks coated with a newly developed nanocoating material. Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) methods are employed to measure the potential environmental loads and economic viability of a real-world twin-bay tunnel project. LCA has been performed with SimaPro software and using ReCiPe endpoint method. The findings indicate that EPS coated with nanocoating material has the lowest environmental impact and cost, with LCA single score of 1.06 MPt and cost reductions of about 14.5% and 27.48% compared to EPS with geomembrane and soil backfilling, respectively. Traditional soil backfilling has the highest environmental impact with a single score of 2.52 MPt. In comparison, EPS with geomembrane has a single score of 2.477 MPt offering a 15.17% cost reduction compared to soil backfilling. Sensitivity analysis concludes that the required amount of reinforced concrete for the tunnel significantly impacts the results. The outcomes support sustainable decision-making for infrastructure solutions.
Journal Article
Molecular Biomarkers and Signaling Pathways of Cancer Stem Cells in Colorectal Cancer
Colorectal cancer (CRC) is the third most frequently found cancer in the world, and it is frequently discovered when it is already far along in its development. About 20% of cases of CRC are metastatic and incurable. There is more and more evidence that colorectal cancer stem cells (CCSCs), which are in charge of tumor growth, recurrence, and resistance to treatment, are what make CRC so different. Because we know more about stem cell biology, we quickly learned about the molecular processes and possible cross-talk between signaling pathways that affect the balance of cells in the gut and cancer. Wnt, Notch, TGF-β, and Hedgehog are examples of signaling pathway members whose genes may change to produce CCSCs. These genes control self-renewal and pluripotency in SCs and then decide the function and phenotype of CCSCs. However, in terms of their ability to create tumors and susceptibility to chemotherapeutic drugs, CSCs differ from normal stem cells and the bulk of tumor cells. This may be the reason for the higher rate of cancer recurrence in patients who underwent both surgery and chemotherapy treatment. Scientists have found that a group of uncontrolled miRNAs related to CCSCs affect stemness properties. These miRNAs control CCSC functions like changing the expression of cell cycle genes, metastasis, and drug resistance mechanisms. CCSC-related miRNAs mostly control signal pathways that are known to be important for CCSC biology. The biomarkers (CD markers and miRNA) for CCSCs and their diagnostic roles are the main topics of this review study.
Journal Article
Resistomycin Suppresses Prostate Cancer Cell Growth by Instigating Oxidative Stress, Mitochondrial Apoptosis, and Cell Cycle Arrest
Globally, prostate cancer is among the most threatening and leading causes of death in men. This study, therefore, aimed to search for an ideal antitumor strategy with high efficacy, low drug resistance, and no or few adverse effects. Resistomycin is a natural antibiotic derived from marine actinomycetes, and it possesses various biological activities. Prostate cancer cells (PC3) were treated with resistomycin (IC12.5: 0.65 or IC25: 1.3 µg/mL) or 5-fluorouracil (5-FU; IC25: 7 µg/mL) for 24 h. MTT assay and flow cytometry were utilized to assess cell viability and apoptosis. Oxidative stress, apoptotic-related markers, and cell cycle were also assessed. The results revealed that the IC50 of resistomycin and 5-FU on PC3 cells were 2.63 µg/mL and 14.44 µg/mL, respectively. Furthermore, treated cells with the high dose of resistomycin showed an increased number of apoptotic cells compared to those treated with the lower dose. Remarkable induction of reactive oxygen species generation and lactate dehydrogenase (LDH) leakage with high malondialdehyde (MDA), carbonyl protein (CP), and 8-hydroxyguanosine (8-OHdG) contents were observed in resistomycin-treated cells. In addition, marked declines in glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in PC3 cells subjected to resistomycin therapy were observed. Resistomycin triggered observable cell apoptosis by increasing Bax, caspase-3, and cytosolic cytochrome c levels and decreasing Bcl-2 levels. In addition, notable downregulation of proliferating cell nuclear antigen (PCNA) and cyclin D1 was observed in resistomycin-treated cancerous cells. According to this evaluation, the antitumor potential of resistomycin, in a concentration-dependent manner, in prostate cancer cells was achieved by triggering oxidative stress, mitochondrial apoptosis, and cell cycle arrest in cancer cells. In conclusion, our investigation suggests that resistomycin can be considered a starting point for developing new chemotherapeutic agents for human prostate cancer.
Journal Article
Optimization of mild steel corrosion inhibition by water hyacinth and common reed extracts in acid media using factorial experimental design
Aquatic macrophytes biomasses provide an opportunity of using their unwanted biomasses that cause ecological disturbance as green corrosion inhibitors. The extracts of water hyacinth (Eichhornia crassipes) and common reed (Phragmits australis) were prepared and assessed, for mild steel corrosion inhibition. The inhibitive effect has been investigated by electrochemical impedance spectroscopy and potentiodynamic polarization techniques. Increasing aquatic and ethanolic extract concentration of both plant extracts increased the inhibition efficiency (% IE). The maximum IE was recorded 86.8 and 89.6% for ethanolic extracts of water hyacinth and common reed. The corrosion current density (i
corr
) was recorded as 0.534 and 0.369 mA cm
−2
for water hyacinth and common reed, respectively, at the maximum concentration. Theoretical fitting of isotherms, Langmuir, Florry-Huggins, and kinetic-thermodynamic models were analyzed to clarify the nature of adsorption behaviour. The % IE of plants extract for mild steel corrosion was evaluated and optimized by 2
(3)
full factorial experimental design. Three factors have been studied namely: extraction method, pH and extract dose. The optimum conditions were at low pH and high plant extract dose concentration especially with ethanolic extraction. The validation models were calculated with R
2
≥ 0.986. The effectiveness of the investigated green inhibitors was also verified using the response surface methodology (RSM).
Journal Article