Zeta Potential Research Articles

Complete Genome Sequence and In Vitro Probiotic Assessment of Bacillus subtilis DC-11 Isolated from Traditionally Fermented Idli Batter.

In this study, we reported in vitro probiotic assessment and complete genome sequence of Bacillus subtilis DC-11 isolated from traditionally fermented Idli Batter. The strain was evaluated for probiotic properties, biofilm formation, and antimicrobial compound production. The phenotypic safety was determined by accessing the strain's ability to produce enterotoxins, degrade mucin, and antibiotic sensitivity. Whole genome sequencing (WGS) was performed to identify the strain and determine genetic safety by analyzing the presence of plasmids, antibiotic resistance genes, and virulence factors. In the results, B. subtilis DC-11 showed 88.98% viability in gastric juice, and 98.60% viability in intestinal juice. It showed 18.33 ± 0.44% autoaggregation, 32.53 ± 3.11% adhesion to xylene, 0.98 ± 0.05 OD unit's adhesion to mucin (crystal violet equivalence at 550nm), 21.2 ± 2.3% adhesion to Caco-2 cells, and - 22.3 ± 0.65mV zeta potential. The highest co-aggregation was recorded with Escherichia coli (23.62 ± 0.70%). The strain was found negative for enterotoxin production, mucin degradation, and antibiotic resistance to the commonly used therapeutic antibiotics. It formed a good biofilm and capable of producing antimicrobial peptide subtilosin A with a molecular mass of 3400Da. The peptide has inhibited the growth of methicillin-resistant Staphylococcus aureus (18.6 ± 0.58mm). In genetic safety, no plasmids, antibiotic-resistant genes, and virulence factors were detected. Moreover, the strain showed close similarity with B. subtilis ATCC 6051 and proteins involved in probiotic attributes. In conclusion, B. subtilis DC-11 is safe potential probiotic candidate.

Pyrite depression by sodium metabisulfite and dextrin with xanthates: contact angle, floatability, zeta potential and IR spectroscopy studies

The individual and combined depressive action of metabisulfite and dextrin on pyrite in the presence and absence of amyl xanthate has been studied through contact angle, zeta potential, microflotation, and IR spectroscopy analyses. The combined application of depressants significantly reduces the contact angle of pyrite compared with that of galena, with this effect being enhanced when the pulp is oxygenated during conditioning with metabisulfite, facilitating pyrite surface oxidation. Zeta potential measurements demonstrate the role of the oxidation process in decreasing the magnitude of the negative electric charge on the pyrite surface. These results were further corroborated by IR spectroscopy studies, which confirmed the oxidation of the pyrite surface in the presence of metabisulfite, as well as the co-adsorption of dextrin and amyl xanthate. In microflotation experiments, pyrite and galena exhibited contrasting flotation behaviors, with pyrite being effectively depressed at pH 8 when a combination of air, metabisulfite, and dextrin was used.

Enhanced Stability and In Vitro Biocompatibility of Chitosan-Coated Lipid Vesicles for Indomethacin Delivery

Background: Lipid vesicles, especially those utilizing biocompatible materials like chitosan (CHIT), hold significant promise for enhancing the stability and release characteristics of drugs such as indomethacin (IND), effectively overcoming the drawbacks associated with conventional drug formulations. Objectives: This study seeks to develop and characterize novel lipid vesicles composed of phosphatidylcholine and CHIT that encapsulate indomethacin (IND-ves), as well as to evaluate their in vitro hemocompatibility. Methods: The systems encapsulating IND were prepared using a molecular droplet self-assembly technique, involving the dissolution of lipids, cholesterol, and indomethacin in ethanol, followed by sonication and the gradual incorporation of a CHIT solution to form stable vesicular structures. The vesicles were characterized in terms of size, morphology, Zeta potential, and encapsulation efficiency and the profile release of drug was assessd. In vitro hemocompatibility was evaluated by measuring erythrocyte lysis and quantifying hemolysis rates. Results: The IND-ves exhibited an entrapment efficiency of 85%, with vesicles averaging 317.6 nm in size, and a Zeta potential of 24 mV, indicating good stability in suspension. In vitro release kinetics demonstrated an extended release profile of IND from the vesicles over 8 h, contrasting with the immediate release observed from plain drug solutions. The hemocompatibility assessment revealed that IND-ves exhibited minimal hemolysis, comparable to control groups, indicating good compatibility with erythrocytes. Conclusions: IND-ves provide a promising approach for modified indomethacin delivery, enhancing stability and hemocompatibility. These findings suggest their potential for effective NSAID delivery, with further in vivo studies required to explore clinical applications.

New Insights into Red and White Quinoa Protein Isolates: Nutritional, Functional, Thermal Properties

Quinoa (Chenopodium quinoa Willd.) seeds, renowned for their nutritional richness and balanced amino acid profile, offer promising potential as food ingredients. This study focused on extracting and characterizing the protein isolates from red and white quinoa varieties to evaluate their physicochemical and functional properties. Protein isolation involved alkaline solubilization and isoelectric precipitation, followed by characterization through amino acid analysis, phenolic profiling, scanning electron microscopy (SEM), zeta potential measurement, particle size distribution analysis, Differential Scanning Calorimetry (DSC), and rheological studies. The results showed that both the red and white quinoa protein isolates exhibited high protein content and essential amino acids, with notable differences in their amino acid compositions. The phenolic and flavonoid content varied between the red and white quinoa seeds, highlighting their potential antioxidant properties. SEM revealed distinct microstructural differences between the red and white quinoa protein isolates. Zeta potential measurements indicated the negative surface charges, influencing the stability in the solution. A particle size distribution analysis showed the monomodal distributions with minor variations in the mean particle size. The DSC profiles demonstrated multiple denaturation peaks, reflecting the complex protein compositions. Rheological studies indicated diverse gelation behaviors and mechanical properties. Overall, this comprehensive characterization underscores the potential of quinoa protein isolates as functional food ingredients with diverse applications in the food industry.

Enhancing the Efficiency and Sustainability of Producing Curcumin‐Infused Plant‐Based Milk Alternatives With a Two‐in‐One Post pH‐Driven Processing Strategy

ABSTRACTIncreasing food sustainability and health benefits is essential to meet the demands of a growing global population while minimizing environmental impact. This study used a green two‐in‐one post pH‐driven processing strategy to develop a sustainable and healthy plant‐based milk alternative. It achieved both extraction and encapsulation in one step by directly incorporating the health‐promoting curcumin from turmeric into soymilk. A high processing efficiency was observed, 94.2% ± 1.6%, with a high extraction efficiency of 96.4% ± 0.5%. Using raw turmeric instead of a purified curcumin significantly enhanced the sustainability in the use of raw materials, for example, reducing the CO2‐eq emissions by 22 times and energy use by 10 times, even with a very small percentage of curcumin (∼0.03 wt%) in the formulation. This strategy underscores the importance of using raw materials and minimizing processing steps to develop more sustainable foods. Additionally, the incorporation of curcumin was found to impart a yellow color to soymilk. No significant changes were observed in other physicochemical properties like particle size, zeta potential, and melting behavior, as most curcumin molecules were encapsulated within the lipid phase of soymilk. The curcumin‐infused soymilk powders also maintained excellent storage stability for 1 month under freezing temperature.

Antimicrobial and Antibiofilm Activity of Green Synthesized Silver Nanoparticles by Using In Vitro Grown Aloe vera L.

In this study, invitro grown Aloe vera L. tissues were used for AgNP synthesis. Adventitious root and callus tissues were grown in MS medium containing 1 mg/L IAA and 1 mg/L NAA. Using A. vera L. leaf, in vitro grown callus, and adventitious roots tissue extracts, AgNPs were synthesized. According to DLS analysis, PDI values and zeta potential values showed that AgNPs from adventitious root were more suitable in terms of size and surface charge. Characterization of adventitious root-derived AgNPs was performed by UV-Vis absorption spectrum, ICP/MS, SEM, FTIR, and XRD. According to HPLC results, catechin, gentisic acid, caffeic acid, coumaric acid, polydatin, coumarin, and ellagic acid were found in adventitious roots. Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC2 7853), MRSA (ATCC 33951) and Staphylococcus aureus (ATCC 6538) strains were used to determine the antibacterial and antibiofilm activity of AgNPs. The highest antibacterial activity was determined against P. aeruginosa. Lower concentrations of AgNPs caused changes in the structure of the biofilm formed by P. aeruginosa, which produced particularly strong biofilms, resulting in failure of biofilm maturation. Accordingly, AgNPs synthesized from Aloe vera L. adventitious roots had antibacterial and antibiofilm activity even at low concentrationsagainst the tested bacterial strains.

Efficient One-Pot Hydrothermal Synthesis of TiO2 Nanostructures for Reactive Black 5 Dye Removal: Experimental and Theoretical Insights

Water scarcity continues to be a major worldwide issue. Therefore, from a scientific perspective, it is crucial to develop a highly effective, affordable, environmentally friendly, and readily available metal-based adsorbent for wastewater treatment. This study focuses on synthesizing a mesoporous/nanosphere TiO2 using a free-template and eco-friendly method to effectively remove Reactive Black 5 (RB5) dye. The synthesis of TiO2 nanospheres was achieved through the use of titanium isopropoxide at 100 °C for 12 h in a one-pot hydrothermal process, successfully regulating their morphology and crystallite size. The TiO2 nanospheres were extensively characterized using multiple techniques, such as XRD, FE-SEM, zeta potential, FT-IR, HR-TEM, and BET surface area tools. Adsorption experiments revealed a notable capacity of 109 mg g−1 for RB5 dye, following pseudo-second-order kinetic behavior. The equilibrium data conformed well to the Langmuir isotherm model, indicating monolayer adsorption. Thermodynamic evaluations confirmed that the process was spontaneous, endothermic, and governed by physisorption. Calculations using density functional theory (DFT) provided additional support for the experimental findings, demonstrating strong binding interactions between the dye and the TiO2 (101) surface. The TiO2 nano-adsorbent showed excellent reusability and maintained high adsorption efficiency over multiple cycles, making it a promising candidate for wastewater treatment.

Antimicrobial activity and cytotoxic and epigenetic effects of tannic acid-loaded chitosan nanoparticles

Tannic acid (TA) is a potent antitumor agent, but its low bioavailability and absorption limit its use. In this study, it was loaded into chitosan-based nanoparticles (Chi-NPs) to overcome these limitations and to improve its antimicrobial and anticancer activities. TA-loaded Chi-NPs (Chi-TA-NPs) were synthesized using the ionic gelation method and physicochemically characterized by FE-SEM, FTIR, XRD, PDI, DLS, and zeta potential analysis. Additionally, the antimicrobial activity of Chi-TA-NPs against two G+ bacterial strains, two G− bacterial strains, and a fungal strain (Candida albicans) was investigated using the microbroth dilution method. MTT assay was used to examine the cytotoxic effects of Chi-TA-NPs on HepG2 cells. The expression of DNA methyltransferase 1 (DNMT1), DNMT3A, and DNMT3B was examined in HepG2 cells using RT-qPCR. The amount of 5-methylcytosine in the HepG2 cell-derived genomic DNA was measured using ELISA. FE-SEM micrographs showed the loading of TA into the chitosan-based formulation. The peaks detected in the XRD and FTIR analyses confirmed the formation of the Chi-TA-NPs. The PDI value (0.247 ± 0.03), size (567.0 ± 25.84 nm), and zeta potential (17.0 ± 5.86 mV) confirmed the relative stability of Chi-TA-NPs. A constant release profile in line with the Korsmeyer-Peppas model was detected for Chi-TA-NPs, such that approximately 44% of TA was released after 300 min. In addition, Chi-TA-NPs exhibited effective antimicrobial activity against the studied microbial strains, as manifested by MIC values ranging from 250 to 1000 µg/mL. Chi-TA-NPs induced cytotoxicity in liver tumor cell line, with an IC50 value of 500 µg/mL. Furthermore, Chi-TA-NPs considerably decreased the expression of DNMT1 (2.52-fold; p = 0.01), DNMT3A (2.96-fold; p = 0.004), and DNMT3B (2.94-fold; p < 0.0001). However, 5-methylcytosine levels in HepG2 cells were unaffected by Chi-TA-NPs treatment (p = 0.62). Finally, the antimicrobial, cytotoxic, and epigenetic effects of Chi-TA-NPs were more pronounced than those of free TA and the unloaded Chi-NPs. In conclusion, Chi-TA-NPs exhibit promising potential for reducing microbial growth and promoting cytotoxicity in liver cancer cells.

Synthesis and evaluation of drug-loaded silver nanoparticles as hemostatic agents to halt uncontrolled bleeding

Objective The aim of this research study was to formulate a cost-effective, stable, less toxic and more efficacious intravenous nanoformulation that could rapidly augment the process of hemostasis. Significance Silver nanoparticles (AgNPs) evoked platelet activation, whereas alum (AM) neutralized the plasma proteins, causing blood coagulation. Tranexamic acid (TA) inhibited fibrinolysis and stabilized the formed blood clot. Methods The nanoformulation (NF) was subjected to characterization techniques such as UV-Vis spectrophotometry, FTIR, XRD, TGA and DSC analysis, which elucidated successful drug conjugation. Results Zeta-sizing confirmed the particle size of NF to be 256.6 nm with 0.497 PDI and a zeta potential of + 9.24 mV. In-vitro release profile exhibited first-order kinetics, indicating sustained release, conferring sustained release of NF for 12 h. NF was hemocompatible at the tested doses, as its extent of hemolysis was < 0.8% and < 1%, following EU and FDA guidelines, respectively. Ex-vivo studies revealed that NF recorded the highest viscosity, i.e., 36.5 cP, and maximum mass of clotted blood, i.e., 17.4 mg, in comparison to other combinations. In-vivo studies indicated a 100-fold dose reduction, i.e. 0.1 mg/kg, compared to the marketed formulation, Transamin® i.e. 10 mg/kg. 10 folds dose reduction i.e. 1 mg/kg, exhibited more efficacious results than Transamin®, owing to the synergistic effect and nano-sizing of components. Conclusion A safe, cost-effective, and relatively less toxic hemostatic nanoparticles were formulated, that can be intravenously administered to halt bleeding within seconds.

Formulation and evaluation of Dapagliflozin -Loaded Ethosomes as Transdermal Drug Delivery Carriers: Statistical Design

Diabetes that includes risk factors for noncommunicable diseases like hypertension are only one example of the various situations in which chronic disease is connected with other conditions. Due to the challenges in overcoming the adverse effects of a complicated therapeutic treatment regimen, the treatments available for such chronic comorbid disorders are restricted and tough. The purpose of this research was to create and refine Dapagliflozin nano vesicular ethosomal gel for use in the treatment of patients with diabetes and cardiovascular disease. Different parameters, such as in-vitro skin permeation, skin irritation, in-vivo antidiabetic, and antihypertensive activities, were used to characterise the developed formulations. Dapagliflozin is a potent, oral, reversible, highly selective, and competitive inhibitor of human SGLT2 used to treat type 2 diabetes. The ethosomes that contain dapagliflozin are the focus of our current study. By incorporating this medication inside lipid nanocarriers, we were able to generate ethosomes, where the vesicular size and lipid used for formulation controlled the sustained release of medicines. The purpose of this study is to create Dapagliflozin-loaded ethosomes for the management of diabetes, and then to statistically optimise and characterise them. For ethosome improvement, we used a 33-level factorial design with three factors. The entrapment efficiency (Y1), vesicle size (Y2), zeta potential (Y3), and % CDR (Y4) were selected as the dependent variables, whereas phosphatidylcholine (X1), cholesterol (X2), and ethanol (X3) were selected as the independent factors. Following incorporation of the optimised ethosomes into Carbopol® 940 gel, their rheological behaviour, in-vitro release, and ex-vivo skin permeation studies were characterised. When compared to drug solutions, in vitro and ex vivo permeation studies yielded more positive results. All things considered, the ethosomal vesicles showed promise as a carrier, allowing for improved topical administration of Dapagliflozin. Keywords: Dapagliflozin, Diabetes, SGLT2, in-vitro release, and ex-vivo, phosphatidylcholine, topical administration, 33-level factorial design.

A Novel Self-Assembled Paclitaxel Nanodispersion Facilitates Rapid In-Vitro/In-Vivo Dissociation and Protein Binding.

The study aims to prepare and characterize a novel paclitaxel (PtX) preconcentrate formulation using polymer and lipid excipients that forms nanodispersion upon dilution. The goal was to understand the mechanism of nanodispersion formation and its properties. The water-insoluble PtX was dissolved in organic solvents containing ethanol, polyethylene glycol (PEG400), povidone (PVP), caprylic acid (CA), and sodium cholesterol sulfate (CS). This formulation was diluted in 5% w/v dextrose medium to form PtX nanodispersion, which was assessed for particle size, stability, in-vitro/in-vivo dissociation and protein binding. Transmission electron microscopy (TEM), Small Angle Neutron Scattering (SANS), and Molecular Dynamics (MD) simulations were used to analyse the structure of the nanoparticles. The formulation was a clear, slightly yellow solution. The PtX nanodispersion displays particle size of ~ 100nm with a zeta potential of -25, and the pH of 4.0. It displayed nearly spherical coacervate nanoparticles with a sponge-like structure, lacking internal structure order as revealed by TEM and SANS. MD simulations confirmed self-assembly of PtX and excipients forming nanoparticles. In vitro dissociation studies in simulated plasma demonstrated rapid dissociation of nanodispersion, releasing free PtX that immediately binds to plasma proteins. In vivo studies in rabbits corroborated these findings, showing rapid dissolution. The results present a novel formulation design that forms sponge-like coacervate nanoparticle due to complimentary interactions of the excipients that otherwise are unable to self-assemble under similar conditions of dilution. This alternative formulation solves the limitations of currently marketed PtX products and can provide its effective delivery in clinical settings.

Chitosan nanoparticles loaded with metformin and digoxin synergistically inhibit MCF-7 breast cancer cells through suppression of NOTCH-1 and HIF-1α gene expression

This study investigated the potential anticancer efficacy of co-treating the MCF-7 breast cancer cell line with chitosan nanoparticles (Cs NPs) loaded with metformin (Met) and digoxin (Dig). The Cs NPs had a size range of 90.6–148.7 nm and a zeta potential of +11.7 to +11.9 mV, indicating a positive surface charge. Notably, the Cs NPs demonstrated high encapsulation efficiencies, with values of 90.97 ± 5.14 % for Met and 92.12 ± 3.81 % for Dig, indicating effective loading of both drugs. The results revealed that the co-delivery of Met and Dig via Cs NPs significantly enhanced the anticancer efficacy, outperforming the treatment with individual free drugs or their combination, thereby demonstrating the potential benefits of nanoparticle-mediated co-administration. The drugs-loaded Cs NPs induced a marked increase in apoptosis in MCF-7 cells, with a cell death rate of 67.56 %, and significantly reduced mammosphere size by 48.08 %, thereby demonstrating a superior therapeutic efficacy compared to treatment with individual free drugs or their combination. Notably, the drug-loaded Cs NPs exhibited potent anti-migratory and anti-angiogenic effects, significantly inhibiting cell migration and new blood vessel formation, which may contribute to overcoming the inherent resistance of tumors to conventional therapies. Mechanistically, the co-treatment with drugs-loaded Cs NPs was found to downregulate the expression of NOTCH-1 and HIF-1α, two key transcription factors involved in tumor cell survival and adaptation, suggesting that their inhibition is a crucial component of the therapeutic efficacy of this treatment strategy. Collectively, the findings of this study suggest that the co-delivery of Met and Dig via chitosan Cs NPs represents a promising therapeutic strategy for breast cancer, as it effectively targets key pathways involved in tumor growth and progression, and underscores the potential of Cs NPs as a versatile platform for cancer therapy.

One-pot green synthesis of zinc oxide nanoparticles using Morus laevigata aqueous extract and evaluation of its anticancer potential against HT-29 cell line

Abstract Colon cancer presents significant challenges in treatment efficiency and patient outcomes, necessitating innovative, effective strategies due to the adverse effects of conventional therapies. The study aimed to investigate the green synthesis of zinc oxide nanoparticles (ZnO NPs) using aqueous extract of Morus laevigata (ML) leaves and their potential biomedical applications. ML-ZnO NPs were characterized using analytical techniques. The absorption band at 330 nm was detected by UV–Vis spectroscopy, confirming the formation of ML-ZnO NPs. An average size of 68.5 ± 1.85 nm and a negative zeta potential of −11.1 ± 0.98 mV confirm the stability of nanoparticles in colloidal solutions. FTIR analysis confirmed ML-ZnO NPs, with absorption bands corresponding to Zn–O stretching vibrations and aliphatic CH and CH2 groups. SEM examination revealed diverse patterns including cauliflower-like formations. Further anticancer activity of ML-ZnO NPs was assessed through cell viability, cell cycle, and apoptosis assays. ML-ZnO NPs inhibited HT-29 cell growth dose dependently, exceeding cisplatin 56.33 ± 0.87% cell viability. Cell cycle arrest at the G2M phase in HT-29 cells treated with ML-ZnO NPs was noticeable, further validated by apoptosis, which showed large increases in apoptotic cell populations. These results may pave the way for future research investigating the potency of ZnO NPs derived from plant extracts to manage colon cancer.

The dependence of the electrokinetic potential of the polymer composition with the resulting solid tape impregnation

The dependence of the electrokinetic potential of the polymer composition with the resulting solid tape impregnation

Model Adequacy in Assessing the Predictive Performance of Regression Models in Pharmaceutical Product Optimization: The Bedaquiline Solid Lipid Nanoparticle Example

This study aimed to assess the predictive performance of first- and second-order regression models in optimizing bedaquiline (BQ) solid lipid nanoparticle (SLN) formulations. A three-step central composite design and graphical optimization process was employed. A design of experiments method was used to evaluate the impact of BQ, Tween 80 (T80), polyethylene glycol (PEG), and lecithin on the formulations’ response variables, including Z-average (PSD), polydispersibility index (PdI), and Zeta potential (ZP). Secondly, we quantified the relationship between experimental variables using the regression model coefficients. Lastly, we predicted the responses and verified the models’ adequacies to ensure accurate representation and effective optimization. The first-order polynomial showed poor model adequacy and required further refinement due to its lack of explanatory power and significant predictors. Conversely, the second-order models provided superior fitness, sensitivity to variability, complexity, and prediction consistency. The optimized formulation achieved a desirability value of 0.9998, indicating alignment with the desired criteria. Specifically, the levels of BQ (19.4 mg), T80 (25.2 mg), PEG (39.2 mg), and lecithin (200 mg) corresponded to PdI (0.41), PSD (250.99 nm), and ZP (−25.95 mV). Maintaining a BQ concentration between 10 and 20% and T80 between 15 and 18% is vital for maximizing ZP and minimizing PdI and PSD, ensuring stable SLN formulations. This study underscores the significance of precise model selection and statistical analysis in pharmaceutical formulation optimization for enhanced drug delivery systems.

Insights into Novel Doping Effect of Fe-Doped ZnS Nanostructures Derived from Oxystelma Esculentum: Kinetics-Based Photocatalysis, Nitrogen Fixation, and Antifungal Efficacy

Implementing greener approaches is a sustainable and eco-friendly methodology for nanocomposite synthesis. This work reports the sustainable fabrication of Fe-doped ZnS (Fe0.3Zn0.7S) nanocomposite and its broad-spectrum applications. The systematic characterization was carried out using several advanced analytical techniques. DLS, Zeta potential, SEM, XPS, and TEM performed morphological and size assessments of the engineered nanocomposite. Eventually, XRD provided valuable insights into the crystalline behavior of nanocomposite. The nanocomposites were then treated against the organic dye Safranin O, which displayed 93% degradation within an hour with the rate constant value of 0.0326 min−1. Parameters influencing the percentage degradation, such as temperature, pH, etc., were also discussed. Moreover, an LCMS test was also conducted to evaluate the presence of reactive intermediates. Safranin O’s degradation was confirmed by identifying intermediate products, such as compounds with m/z values of 335.84, 321.81, 306.79, 292.77, and 257.32, which were indicative of progressive dye breakdown. Finally, the photocatalytic enactment examination verified that the prepared nanocomposite’s nitrogen fixation rate (38.96 µmolg−1) was way greater (~4 times) than the pristine compound. In addition, prepared nanoparticles demonstrated a befitting ability to eliminate a wide range of threatening pathogenic fungi. The doping of Fe into ZnS further enhanced the inhibition against Fusarium oxysporum.

Promotive Effect of Organic Acids on the Dispersion of Ceria Slurry and the Removal Rate of TEOS in Chemical Mechanical Polishing

Abstract In this study, the effect of organic acids (formic acid, acetic acid, and lactic acid) on the material removal rate (MRR) of TEOS films was investigated. The results showed that formic acid was an effective dispersant for CeO2 slurry. When adding formic acid to the slurry, the average particle size of CeO2 was reduced to 172.5 nm and the Zeta potential was increased to 47.6 mV. Consequently, the MRR of TEOS improved from 408.3 to 695.5 nm/min with a surface roughness of 0.16 nm. The MRR of the pattern wafer was increased from 575.1 to 941.6 nm/min. Molecular dynamics simulation indicated that the oxygen atom attached to the double bond in the carboxyl group serves as the primary electrophilic reaction site. The double electric layer was thickest between formic acid and CeO2, resulting in the best dispersion of CeO2 slurry, which was conducive to improving the MRR of TEOS. The polishing effect of formic acid was verified by adding polyethylene glycol, enhancing the MRR of TEOS was 1351.2 nm/min.

Nanomedicine based on chemotherapy-induced immunogenic death combined with immunotherapy to enhance antitumor immunity

IntroductionChemo-immunotherapy based on inducing tumor immunogenic cell death (ICD)with chemotherapy drugs has filled the gaps between traditional chemotherapy and immunotherapy. It is verified that paclitaxel (PTX) can induce breast tumor ICD. From this basis, a kind of nanoparticle that can efficiently deliver different drug components simultaneously is constructed. The purpose of this study is for the sake of exploring the scheme of chemotherapy-induced ICD combined with other immunotherapy to enhance tumor immunogenicity and inhibit the growth, metastasis, and recurrence of breast tumors, so as to provide a research basis for solving the tough problem of breast cancer treatment.MethodsNanomedicine loaded with PTX, small interference RNA that suppresses CD47 expression (CD47siRNA, siCD47), and immunomodulator R848 were prepared by the double emulsification method. The hydrodynamic diameter and zeta potential of NP/PTX/siCD47/R848 were characterized. Established the tumor-bearing mice model of mouse breast cancer cell line (4T1) in situ and observed the effect of intravenous injection of NP/PTX/siCD47/R848 on the growth of 4T1 tumor in situ. Flow cytometry was used to detect the effect of drugs on tumor immune cells.ResultsNP/PTX/siCD47/R848 nano-drug with tumor therapeutic potential were successfully prepared by double emulsification method, with particle size of 121.5 ± 4.5 nm and surface potential of 36.1 ± 2.5 mV. The calreticulin on the surface of cell membrane and extracellular ATP or HMGB1 of 4T1 cells increased through treatment with NPs. NP/PTX-treated tumor cells could cause activation of BMDCs and BMDMs. After intravenous injection, NP/PTX could quickly reach the tumor site and accumulate for 24 h. The weight and volume of tumor in situ in the breast cancer model mice injected with nanomedicine through the tail vein were significantly lower than those in the PBS group. The ratio of CD8+/CD4+ T cells in the tumor microenvironment and the percentage of dendritic cells in peripheral blood increased significantly in breast cancer model mice injected with nano-drugs through the tail vein.DiscussionBriefly, the chemotherapeutic drug paclitaxel can induce breast cancer to induce ICD. The nanomedicine which can deliver PTX, CD47siRNA, and R848 at the same time was prepared by double emulsification. NP/PTX/siCD47/R848 nano-drug can be enriched in the tumor site. The experiment of 4T1 cell tumor-bearing mice shows that the nano-drug can enhance tumor immunogenicity and inhibit breast tumor growth, which provides a new scheme for breast cancer treatment. (Graphical abstract)

Synthesis of Polymeric Nanoparticles Using Fungal Biosurfactant as Stabilizer

Polymeric nanoparticles (PNPs) are highly valuable across various industries due to their advantageous properties, including biocompatibility and enhanced release control, which are particularly important for pharmaceutical and cosmetic applications. Fungi, through secondary metabolism, are capable of producing biosurfactants (BSs)—amphiphilic molecules that reduce surface tension and can therefore substitute synthetic surfactants in PNP stabilization. In this study, we investigated the production of biosurfactants by the endophytic fungus Aspergillus welwitschiae CG2-16, isolated from the Amazon region, as well as its use as a PNP stabilizer. The fungus exhibited a 36% reduction in the surface tension of the culture medium during growth, indicative of BS production. The partially purified biosurfactant demonstrated an emulsification of 24%, a critical micelle concentration (CMC) of 280 mg/L, and an FTIR spectrum suggesting a lipopeptide composition. The biosurfactant was employed in the synthesis of poly-ε-caprolactone (PCL) nanoparticles via nanoprecipitation and emulsion/diffusion methods. Nanoprecipitation yielded spherical nanoparticles with a low polydispersity index (0.14 ± 0.04) and a high zeta potential (−29.10 ± 8.70 mV), indicating suspension stability. These findings highlight the significant role of biosurfactants in polymeric nanoparticle formation and stabilization, emphasizing their potential for diverse applications in pharmaceutical, cosmetic, and other industrial sectors.

Enhanced sludge solid-liquid separation based on Fe2+/periodate conditioning coupled with polyoxometalates: Cell destruction and protein adsorption

Dewatering of waste activated sludge is a necessary step for achieving subsequent reduction, stabilization, and resource utilization. In this study, Fe2+/periodate (PI) coupled with polyoxometalates (POMs) conditioning was tested for realizing sludge deep dewatering. After the addition of POMs (0.20 mmol g−1 VSS), Fe2+/PI/POMs conditioning enhanced the efficiency of sludge dewatering by 42.93% compared to Fe2+/PI conditioning. It was found that the electrostatic repulsion posed a significant influence on the interaction between POMs and proteins. The reduction of electrostatic repulsion facilitated the proximity of POMs to the sludge flocs and promoted its reaction. The strong acidity and interaction with cells of POMs could induce the damage or apoptosis in sludge cells, resulting in the release of intracellular substances. The active radicals generated by Fe2+/PI process attacked TB-EPS, causing the dissolution of EPS and the decomposition of hydrophilic substances. With the assistance of Fe2+/PI process, POMs exhibited an enhanced cell-disruptive effect, thereby inducing the liberation of a greater quantity of intracellular substances. Moreover, Fe2+/PI/POMs conditioning effectively lowered the zeta potential of sludge system, facilitating the interaction between negatively charged POMs anions and the positively charged regions of proteins. This interaction tended to favor adsorption and precipitation rather than destruction. The adsorption and sedimentation of proteins by POMs further reduced the hydrophilicity of sludge system, thereby enhancing sludge dewaterability. Furthermore, POMs could enhance the electron transfer capacity of sludge system, which was beneficial for subsequent filtrate denitrification treatment.