Agglomeration of Silicon Dioxide Nanoscale Colloids in Chemical Mechanical Polishing Wastewater: Influence of pH and Coagulant Concentration

Abstract Chemical mechanical polishing (CMP) wastewater generated from semiconductor manufacturing industries is known to contain residual organic and inorganic contaminants, i.e. photoresists, acids, including silicon dioxide (SiO2), nanoparticles (NPs) and others. Nanoscale colloids in CMP wastewater have strong inclination to remain in the suspension, leading to high turbidity and chemical oxygen demand (COD). Although various types of pre-treatment have been implemented, these nanoparticles remain diffused in small clusters that pass through the treatment system. Therefore, it is crucial to select suitable pH and coagulant type in the coagulation treatment process. In this research zeta potential and dynamic light scattering measurements are applied as preliminary step aimed at determining optimum pH and coagulant dosage range based on the observation of inter particle-particle behavior in a CMP suspension. The first phase of the conducted study is to analyze nanoscale colloids in the CMP suspension in terms of zeta potential and z-average particle size as a function of pH within a range of 2 to 12. Two types of coagulants were investigated - polyaluminum chloride (PACl) and ferrous sulfate heptahydrate (FeSO4·7H2O). Similar pH analysis was conducted for the coagulants with the same pH range separately. The second phase of the study involved evaluating the interaction between nanoscale colloids and coagulants in the suspension. The dynamics of zeta potential and corresponding particle size were observed as a function of coagulant concentration. Results indicated that CMP wastewater is negatively charged, with average zeta potential of -59.8 mV and 149 d.nm at pH value of 8.7. The interaction between CMP wastewater and PACl showed that positively charged PACl rapidly adsorbed colloids in the wastewater, reducing the negative surface charge of nanoscale clusters. The interaction between CMP wastewater and FeSO4·7H2O showed that larger dosage is required to aggregate nanoscale clusters, due to its low positive value to counter negative charges of CMP wastewater.

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Preparation and characterization of natural quercetin-based Mongolia Medicine SenDeng-4 nanoemulsion (N-QUE-NE) and its antibacterial activity..

Current Drug Delivery ◽

10.2174/1567201818666201214143631 ◽

2020 ◽

Vol 18 ◽

Author(s):

Yanfang Zhang ◽

Rina Du ◽

Pengwei Zhao ◽

Sha Lu ◽

Rina Wu ◽

...

Keyword(s):

Particle Size ◽

Antibacterial Activity ◽

Zeta Potential ◽

High Speed ◽

Antibacterial Effect ◽

Average Particle Size ◽

Antagonistic Effect ◽

Dilution Method ◽

Average Particle

Background: Quercetin is the main active ingredient of Xanthoceras sorbifolia Bunge. Traditional compatibility theory of traditional Chinese medicine has typically reported a synergistic interaction among multiple components, while the synergistic effects of nanoemulsion have not been fully clarified. Objective: To study preparation and characterization of quercetin-based Mongolia Medicine Sendeng-4 nanoemulsion (NQUE-NE) and its antibacterial activity and mechanisms. Methods: The morphology of the nanoemulsion was observed by transmission electron microscopy (TEM), and the zeta potential, polydispersity index (PDI), and particle size distribution were determined by the nanometer particle size analyze. The stability of nanoemulsion was investigated by light test, high speed centrifugal test and storage experiment at different temperature. The combined bacteriostatic effect of N-QUE-NE was studied in vitro by double-dilution method and checkerboard dilution method. Results: The appearance of N-QUE-NE was pale yellow, clear and transparent. The nanoemulsion particles were spherical and uniformly distributed under TEM. The PDI was 0.052, the average particle size was 19.6nm, and the Zeta potential was -0.2mV. When quercetin nanoemulsion (QUE-NE) was used in combination with tannin nanoemulsion (TAN-NE) and toosendanin nanoemulsion (TOO-NE), it exhibited a synergistic antibacterial effect. However, the combination of QUE-NE and geniposide nanoemulsion (GEN-NE) exhibited an antagonistic effect. It was revealed that the antibacterial effect was in order of quercetin-tannin-toosendanin nanoemulsion (QUE-TAN-TOO-NE) ＞ quercetin-tannin nanoemulsion (QUE-TANNE) ＞ QUE-NE ＞ quercetin-tannin-toosendanin-geniposide nanoemulsion (QUE-TAN-TOO-GEN-NE). Conclusion: This study explored the preparation and efficacy of N-QUE-NE, and the results showed that quercetin, tannin and toosendanin had satisfactory synergistic antibacterial effects. The antagonistic effect of quercetin and geniposide in nanoemulsion indicated that it is not beneficial to the antibacterial effect of Sendeng-4, and further research needs to be conducted to clarify its antibacterial effect.

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Formulation and Evaluation of Polymeric Nanoparticles of an Antiviral Drug for Gastroretention

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2011.4.4.6 ◽

2012 ◽

Vol 4 (4) ◽

pp. 1557-1562 ◽

Cited By ~ 1

Author(s):

Ankit Anand Kharia ◽

A K Singhai ◽

R Verma

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Average Particle Size ◽

Chlorinated Solvents ◽

Entrapment Efficiency ◽

The Body ◽

Hydrophilic Polymers ◽

Polydispersity Index ◽

Average Particle ◽

Loading Efficiency

The aim of present study was to formulate and evaluate nanoparticles of acyclovir by using different hydrophilic polymers. Acyclovir was selected as a suitable drug for gastro-retentive nanoparticles due to its short half life, low bioavailability, high frequency of administration, and narrow absorption window in stomach and upper part of GIT. The nano-precipitation method was used to prepare nanoparticles so as to avoid both chlorinated solvents and surfactants to prevent their toxic effect on the body. Nanoparticles of acyclovir were prepared by using hydrophilic polymers such as bovine serum albumin, chitosan, and gelatin. The prepared formulations were then characterized for particle size, polydispersity index, zeta potential, loading efficiency, encapsulation efficiency and drug-excipient compatibility. The prepared nanoparticulate formulations of acyclovir with different polymers in 1:1 ratio have shown particle size in the range of 250.12-743.07 nm, polydispersity index (PDI) in the range of 0.681-1.0, zeta potential in the range of -14.2 to +33.2 mV, loading efficiency in the range of 8.74-17.54%, and entrapment efficiency in the range of 55.7%-74.2%. Nanoparticulate formulation prepared with chitosan in 1:1 ratio showed satisfactory results i.e. average particle size 312.04 nm, polydispersity index 0.681, zeta potential 33.2 mV, loading efficiency 17.54%, and entrapment efficiency 73.4%. FTIR study concluded that no major interaction occurred between the drug and polymers used in the present study.

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Effect of Poly(Vinyl Pyrrolidone) on Dispersing Carbon Black Particles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.796.432 ◽

2013 ◽

Vol 796 ◽

pp. 432-436

Author(s):

Xia Yuan

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Carbon Black ◽

Ultrasonic Method ◽

Aqueous Media ◽

Average Particle Size ◽

Sodium Dodecyl ◽

Vinyl Pyrrolidone ◽

Average Particle ◽

Poly Vinyl Pyrrolidone

The effects of poly (vinyl pyrrolidone)(PVP) on dispersing carbon black (CB) particles were investigated by measuring Z-average particle size, Zeta potential and centrifugal stability of CB dispersions. Addition of PVP in a dispersing medium significantly reduces the size of suspended CB particles, especially in water. The dispersing efficiency of PVP was found to have been enhanced by adding an anionic surfactant, sodium methylenedinaphthalene disulphonate (NNO) in the aqueous media. The particle size of CB dispersed with PVP and NNO was 175.7 nm, significantly smaller than that dispersed with PVP and sodium dodecyl sulfate (SDS). The performance of PVP-encapsulated CB particles and that of PVP-adsorbed CB particles were also compared. The particle size and Zeta potential of PVP-encapsulated CB particles were similar to those of PVP-adsorbed CB particles using ultrasonic method, but the centrifugal stability of PVP-encapsulated CB dispersions was significantly improved. The relative absorbency of PVP/CB dispersions was increased from 42.0% to 63.7%. However, the PVP-encapsulated layer can be destroyed by prolonged ultrasonic treatment because the ultrasound over a long period of time can not only break up the flocculation bridge in the crosslinking matrix of PVP, but also flake off the PVP shells on the surface of CB particles.

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Influence of Second Phase Particles on Fracture Toughness in AZ31 Magnesium Alloys

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.261-263.369 ◽

2004 ◽

Vol 261-263 ◽

pp. 369-374 ◽

Cited By ~ 14

Author(s):

Taisuke Sasaki ◽

Hidetoshi Somekawa ◽

Akira Takara ◽

Yukio Nishikawa ◽

Kenji Higashi

Keyword(s):

Fracture Toughness ◽

Particle Size ◽

Magnesium Alloys ◽

Average Particle Size ◽

Second Phase ◽

Average Particle ◽

Particle Spacing ◽

Strain Fracture ◽

Second Phase Particles ◽

Good Agreement

Three kinds of thin AZ31 wrought magnesium alloys sheets were used in order to investigate the influence of the second phase particles on fracture toughness. From the theoretical model, the ratio of λp/dp would be estimated 5~ 6. On the other hand, from the microstructural observation, average particle spacing on each material was sample A: 13.1µm, sample B: 14.1, and sample C: 12 µ. In addition, average particle size on each sample was sample A: 2.1, sample B: 1.9, and sample C: 2.3 µm. Therefore, the ratio of λp/dp calculated from fracture surface observation would be predicted 6 ~ 7. In comparison with the result of the prediction by theoretical analysis was in good agreement with the result of fracture toughness observation. It was found that the variation in plane-strain fracture toughness on AZ31 were affected by both of particle spacing and particle size.

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Effect of the Dispersion State in Y5O4F7 Suspension on YOF Coating Deposited by Suspension Plasma Spray

Coatings ◽

10.3390/coatings11070831 ◽

2021 ◽

Vol 11 (7) ◽

pp. 831

Author(s):

Seungjun Lee ◽

Jaehoo Lee ◽

Nongmoon Hwang

Keyword(s):

Particle Size ◽

Light Scattering ◽

Dynamic Light Scattering ◽

Zeta Potential ◽

Average Particle Size ◽

Average Particle ◽

Electrophoretic Light Scattering ◽

Electrosteric Stabilization ◽

Dispersion State ◽

Yttrium Oxyfluoride

The stable Y5O4F7 suspension for dense yttrium oxyfluoride (YOF) coating by suspension plasma spraying (SPS) was developed. Electrostatically and electrosterically stabilized aqueous Y5O4F7 suspensions were prepared and compared with a commercially available Y5O4F7 suspension without dispersant. The wettability and dispersibility of the Y5O4F7 suspensions were evaluated in terms of the zeta potential, average particle size, and size distribution with electrophoretic light scattering (ELS) and dynamic light scattering (DLS). The viscosity was measured and the sedimentation was tested to examine the fluidity and stability of the Y5O4F7 suspensions. When electrostatic (BYK-154) and electrosteric (BYK-199) dispersants were added to the Y5O4F7 suspension, the isoelectric point (IEP) of Y5O4F7 particles in the suspension shifted to lower pH. The zeta potential of both of electrostatically and electrosterically stabilized Y5O4F7 suspensions were higher than ±40 mV at pH of 8.6, respectively, which were much higher than of the Y5O4F7 suspension without dispersant. Meanwhile, the average particle size of the electrosterically stabilized Y5O4F7 suspension was much smaller than that of the electrostatically stabilized one. The electrosteric stabilization had a great effect on improving the wettability and dispersibility of the Y5O4F7 suspension. The coating rate of the electrosterically stabilized Y5O4F7 suspension was the highest among the three tested suspensions. In addition, the YOF coating deposited with the electrosterically stabilized Y5O4F7 suspension had the highest hardness and the lowest porosity.

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Chemical Mechanical Polishing Slurry for Tungsten in ULSI With Large Particle Size Colloidal Silica Nano-Abrasive

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-64249 ◽

2005 ◽

Author(s):

Kailiang Zhang ◽

Zhitang Song ◽

Songlin Feng

Keyword(s):

Surface Roughness ◽

Particle Size ◽

Zeta Potential ◽

Chemical Mechanical Polishing ◽

Large Particle ◽

Colloidal Silica ◽

Removal Rate ◽

Silica Sol ◽

Mechanical Polishing ◽

Large Particle Size

Silica sol nano-abrasives with large particle are prepared and characterized by TEM, PCS and Zeta potential in this paper. Results show that the silica sol nano-abrasives about 100nm are of higher stability (Zeta potential: −65mV) and narrow distribution of particle size. And then alkali CMP slurries for tungsten containing self-made silica sol nano-abrasives are prepared and applied. CMP results show that the removal rate has been improved to 367nm/min and the RMS of surface roughness has been reduced from 4.4nm to 0.80nm. In sum, one kind of alkali slurry containing 100nm silica sol for tungsten CMP is studied.

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BIO-NANOPARTICLES: GREEN SYNTHESIS OF GOLD NANOPARTICLES AND ASSESSMENT OF BIOLOGICAL EVALUATION

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2019v11i6.34826 ◽

2019 ◽

pp. 133-138

Author(s):

RATIH DYAH PERTIWI ◽

SUWALDI ◽

ERNA PRAWITA SETYOWATI ◽

RONNY MARTIEN

Keyword(s):

Particle Size ◽

Gold Nanoparticles ◽

Zeta Potential ◽

Absorption Spectra ◽

Biological Activities ◽

Average Particle Size ◽

Antioxidant Properties ◽

Biological Evaluation ◽

Nano Particles ◽

Average Particle

Objective: The design like bio-nano particles are beneficial over chemical and physical composition due to the eco-friendly and lower-cost synthesis of nanoparticles. The current study was purposed for the biosynthesis of gold nanoparticles (GNPs) and their antioxidant evaluation. Methods: Aqua extract of Muntingia calabura, Linn was applied for the synthesis of GNPs and confirmed by UV visible and ATR-Fourier Transform Infra-Red (ATR-FTIR) spectroscopy. Transmission Electron Microscope and Particle Size Analyser were used for the shape zeta potential and determination of size. Antioxidant activity was examined by DPPH (1,1 diphenyl-2-picryl-hydrazyl) radical scavenging method. Results: The result showed that UV–vis absorption spectra of H Au Cl4 at 290 nm while absorption spectra of biosynthesis gold nanoparticles at 540 nm. The forming of nanoparticles were spherical, having an average particle size of 88 nm, and the result of zeta potential was 9.5 mV. Analysis of ATR-FTIR revealed the possible involvement of phytochemical constituents in gold nanoparticles of aqua extract. Green synthesized nanoparticles showed enhanced antioxidant properties. Conclusion: Green synthesized GNPs showed enhanced biological activities. Present results also support the benefit of using the biosynthesis method for the production of gold nanoparticles that have the potential of antioxidant and biology activities.

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Improving the Intercellular Uptake and Osteogenic Potency of Calcium Phosphate via Nanocomplexation with the RALA Peptide

Nanomaterials ◽

10.3390/nano10122442 ◽

2020 ◽

Vol 10 (12) ◽

pp. 2442

Author(s):

Michelle O’Doherty ◽

Eoghan J. Mulholland ◽

Philip Chambers ◽

Sreekanth Pentlavalli ◽

Monika Ziminska ◽

...

Keyword(s):

Particle Size ◽

Calcium Phosphate ◽

Zeta Potential ◽

Average Particle Size ◽

Average Particle ◽

Type I ◽

Amphipathic Peptide ◽

Matrix Deposition ◽

Post Transfection ◽

Osteogenic Response

Calcium phosphate-base materials (e.g., alpha tri-calcium phosphate (α–TCP)) have been shown to promote osteogenic differentiation of stem/progenitor cells, enhance osteoblast osteogenic activity and mediate in vivo bone tissue formation. However, variable particle size and hydrophilicity of the calcium phosphate result in an extremely low bioavailability. Therefore, an effective delivery system is required that can encapsulate the calcium phosphate, improve cellular entry and, consequently, elicit a potent osteogenic response in osteoblasts. In this study, collagenous matrix deposition and extracellular matrix mineralization of osteoblast lineage cells were assessed to investigate osteogenesis following intracellular delivery of α-TCP nanoparticles. The nanoparticles were formed via condensation with a novel, cationic 30 mer amphipathic peptide (RALA). Nanoparticles prepared at a mass ratio of 5:1 demonstrated an average particle size of 43 nm with a zeta potential of +26 mV. The average particle size and zeta potential remained stable for up to 28 days at room temperature and across a range of temperatures (4–37 °C). Cell viability decreased 24 h post-transfection following RALA/α-TCP nanoparticle treatment; however, recovery ensued by Day 7. Immunocytochemistry staining for Type I collagen up to Day 21 post-transfection with RALA/α-TCP nanoparticles (NPs) in MG-63 cells exhibited a significant enhancement in collagen expression and deposition compared to an untreated control. Furthermore, in porcine mesenchymal stem cells (pMSCs), there was enhanced mineralization compared to α–TCP alone. Taken together these data demonstrate that internalization of RALA/α-TCP NPs elicits a potent osteogenic response in both MG-63 and pMSCs.

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Third-Generation Cephalosporin-Loaded Chitosan Used to Limit Microorganisms Resistance

Materials ◽

10.3390/ma13214792 ◽

2020 ◽

Vol 13 (21) ◽

pp. 4792

Author(s):

Letiția Doina Duceac ◽

Gabriela Calin ◽

Lucian Eva ◽

Constantin Marcu ◽

Elena Roxana Bogdan Goroftei ◽

...

Keyword(s):

Particle Size ◽

Antibiotic Resistance ◽

Zeta Potential ◽

Average Particle Size ◽

Chitosan Nanoparticles ◽

World Health ◽

Multi Drug Resistance ◽

Prolonged Release ◽

Average Particle ◽

Gravimetric Analysis

From their discovery, antibiotics have significantly improved clinical treatments of infections, thus leading to diminishing morbidity and mortality in critical care patients, as well as surgical, transplant and other types of medical procedures. In contemporary medicine, a significant debate regarding the development of multi-drug resistance involves all types of pathogens, especially in acute care hospitals due to suboptimal or inappropriate therapy. The possibility of nanotechnology using nanoparticles as matrices to encapsulate a lot of active molecules should increase drug efficacy, limit adverse effects and be an alternative helping to combat antibiotic resistance. The major aim of this study was to obtain and to analyze physico-chemical features of chitosan used as a drug-delivery system in order to stop the antibiotic resistance of different pathogens. It is well known that World Health Organization stated that multidrug resistance is one of the most important health threats worldwide. In last few years, nano-medicine emerged as an improved therapy to combat antibiotic-resistant infections agents. This work relies on enhancement of the antimicrobial efficiency of ceftriaxone against gram(+) and gram(−) bacteria by antibiotic encapsulation into chitosan nanoparticles. Physicochemical features of ceftriaxone-loaded polymer nanoparticles were investigated by particle size distribution and zeta potential, Fourier-transform infrared spectroscopy (FTIR), Thermal Gravimetric Analysis (TG/TGA), Scanning Electron Microscopy (SEM) characteristics techniques. The obtained results revealed an average particle size of 250 nm and a zeta potential value of 38.5 mV. The release profile indicates an incipient drug deliverance of almost 15%, after 2 h of approximately 83%, followed by a slowed drug release up to 24 h. Characteristics peaks of chitosan were confirmed by FTIR spectra indicating a similar structure in the case of ceftriaxone-loaded chitosan nanoparticles. A good encapsulation of the antibiotic into chitosan nanoparticles was also provided by thermo-gravimetric analysis. Morphological characteristics shown by SEM micrographs exhibit spherical nanoparticles of 30–250 nm in size with agglomerated architectures. Chitosan, a natural polymer which is used to load different drugs, provides sustained and prolonged release of antibiotics at a specific target by possessing antimicrobial activity against gram(+) and gram(−) bacteria. In this research, ceftriaxone-loaded chitosan nanoparticles were investigated as a carrier in antibiotic delivery.

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Adsorption of Hazardous Heavy Metals Using Reactive Inorganic Agents in Synthetic Wastewater

Materials Science Forum ◽

10.4028/www.scientific.net/msf.658.5 ◽

2010 ◽

Vol 658 ◽

pp. 5-8

Author(s):

Jong Oh Kim ◽

Jin Woo Lee

Keyword(s):

Heavy Metals ◽

Particle Size ◽

Zeta Potential ◽

Adsorption Capacity ◽

Average Particle Size ◽

Synthetic Wastewater ◽

Average Particle ◽

Xrf Analysis ◽

Reactive Agents ◽

Main Components

This study focused on the adsorption characteristics of hazardous heavy metals using reactive inorganic agents in synthetic wastewater. Basic properties of five reactive agents were analyzed by zeta potential, particle size, XRF and SEM. Zeta potential of five adsorbents was 45, 7, 14, -2 and 45 mV, respectively. Average particle size was in the range of 1.4 to 9㎛. By XRF analysis, main components were Na, Al, Si, S and Fe in reactive agents and no great differences in Mg, K, Ca and Ti components. As, Zn, Ni, Cu, Cr, Cd and Pb were used as target heavy metals. Adsorption capacity of Pb and Cu was in the order: TN 315Ny-T3>TN820L>TN315NY.

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