1
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Polycation-stabilized PDADMAC-gold nanoparticles as a highly sensitive colorimetric sensor for the detection of the chlorpyrifos pesticide. Colloid Polym Sci 2023. [DOI: 10.1007/s00396-023-05058-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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2
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Huang Y, Sato S, Kobayashi M. Conditions for Shake-Gel Formation: The Relationship between the Size of Poly(Ethylene Oxide) and the Distance between Silica Particles. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27227770. [PMID: 36431870 PMCID: PMC9699258 DOI: 10.3390/molecules27227770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 11/06/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022]
Abstract
Colloidal silica suspensions are widely used in many fields, including environmental restoration, oil drilling, and food and medical industries. To control the rheological property of suspensions, poly(ethylene oxide) (PEO) polymers are often used. Under specific conditions, the silica-PEO suspension can create a phenomenon called a shake-gel. Previous works discussed the conditions necessary to form a shake-gel and suggested that the bridging effect of the polymer is one of the important mechanisms for shake-gel formation. However, we noted that the influence of PEO size compared to the separation distance between silica particles regarding shake-gel formation has not been systematically investigated, while the PEO size should be larger than the particle-particle separation distance for polymer bridging in order to form gels. Thus, we conducted a series of experiments to examine the effects of the radius of gyration of the PEO and the distance between the silica particles by controlling the PEO molecular weight and the silica concentration. Our results elucidated that the radius of gyration of the PEO should be 2.5 times larger than the distance between the silica surfaces in order to promote the formation of a shake-gel. This result supports the hypothesis that the bridging effect is the main cause of shake-gel formation, which can help us to understand the conditions necessary for shake-gel preparation.
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Affiliation(s)
- Yi Huang
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8572, Japan
| | - Shunsuke Sato
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8572, Japan
| | - Motoyoshi Kobayashi
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8572, Japan
- Correspondence:
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3
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The Effect of Sulfobetaine Coating in Inhibiting the Interaction between Lyotropic Liquid Crystalline Nanogels and Proteins. Gels 2022; 8:gels8100653. [PMID: 36286154 PMCID: PMC9602168 DOI: 10.3390/gels8100653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/09/2022] [Accepted: 10/12/2022] [Indexed: 11/04/2022] Open
Abstract
The injective lyotropic liquid crystalline nanogels (LLCNs) were widely used in drug delivery systems. But when administered in vivo, LLCNs exposed to the biological environment interact with proteins. Recently, it has been shown that nanoparticles coated with zwitterions can inhibit their interaction with proteins. Thus, in this study, the interaction between proteins and LLCNs coated with the zwitterionic material sulfobetaine (GLLCNs@HDSB) was investigated using bovine serum albumin (BSA) as a model protein. Interestingly, it was found that GLLCNs@HDSB at higher concentrations (≥0.8 mg/mL) could block its interaction with BSA, but not at lower concentrations (<0.8 mg/mL), according to the results of ultraviolet, fluorescence, and circular dichroism spectra. In the ultraviolet spectra, the absorbance of GLLCNs@HDSB (0.8 mg/mL) was 1.9 times higher than that without the sulfobetaine coating (GLLCNs) after incubation with protein; the fluorescence quenching intensity of GLLCNs@HDSB was conversely larger than that of the GLLCNs; in circular dichroism spectra, the ellipticity value of GLLCNs@HDSB was significantly smaller than that of the GLLCNs, and the change in GLLCNs@HDSB was 10 times higher than that of the GLLCNs. Generally, nanoparticles coated with sulfobetaine can inhibit their interaction with proteins, but in this study, LLCNs showed a concentration-dependent inhibitory effect. It could be inferred that in contrast to the surface of nanoparticles covered with sulfobetaine in other cases, the sulfobetaine in this study interacted with the LLCNs and was partially inserted into the hydrophobic region of the LLCNs. In conclusion, this study suggests that coating-modified nanoparticles do not necessarily avoid interacting with proteins, and we should also study coating-modified nanoparticles interacting with proteins both in vitro and in vivo. In the future, finding a coating material to completely inhibit the interaction between LLCNs and proteins will generate a great impetus to promote the clinical transformation of LLCNs.
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4
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Aggregation and charging of natural allophane particles in the presence of oxyanions. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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5
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Effect of pH and electrolyte concentration on sol–gel state of semi-dilute aqueous cellulose nanofiber suspension: an interpretation based on angle-dependent DLVO theory. Colloid Polym Sci 2022. [DOI: 10.1007/s00396-022-04999-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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6
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Geonzon LC, Kobayashi M, Sugimoto T, Adachi Y. Study on the kinetics of adsorption of poly(ethylene oxide) onto a silica particle using optical tweezers and microfluidics. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.128691] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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7
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Li M, Kobayashi M. The aggregation and charging of natural clay allophane: Critical coagulation ionic strength in the presence of multivalent counter-ions. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.127021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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8
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Chapa-Rodríguez R, Avila-de la Rosa G, Pérez E. Thermal stability and ageing properties of PP–PE film modulated by nano-silica particles: comparison between dry and moist particles. Polym Bull (Berl) 2021. [DOI: 10.1007/s00289-020-03258-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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9
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Omija K, Hakim A, Masuda K, Yamaguchi A, Kobayashi M. Effect of counter ion valence and pH on the aggregation and charging of oxidized carbon nanohorn (CNHox) in aqueous solution. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.126552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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10
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Pham TD, Le TMA, Pham TMQ, Dang VH, Vu KL, Tran TK, Hoang TH. Synthesis and Characterization of Novel Hybridized CeO 2@SiO 2 Nanoparticles Based on Rice Husk and Their Application in Antibiotic Removal. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:2963-2973. [PMID: 33591197 DOI: 10.1021/acs.langmuir.0c03632] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This work aims to synthesize a core-shell material of CeO2@SiO2 based on rice husk as a novel hybridized adsorbent for antibiotic removal. The phase structures of CeO2@SiO2 and CeO2 nanoparticles that were fabricated by a simple procedure were examined by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared (FT-IR) spectroscopy, while their interfacial characterizations were performed by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), the Brunauer-Emmett-Teller (BET) method, and ζ-potential measurements. The removal efficiency of the antibiotic amoxicillin (AMX) using CeO2@SiO2 nanoparticles was much greater than that using SiO2 and CeO2 materials in solutions of different pH values. The optimum conditions for AMX removal using CeO2@SiO2 including contact time and adsorbent dosage were 120 min and 5 mg/mL, respectively. The maximum AMX removal using CeO2@SiO2 reached 100% and the adsorption capacity was 12.5 mg/g. Adsorption isotherms of AMX onto CeO2@SiO2 were fitted by Langmuir, Freundlich, and two-step adsorption models, while the adsorption kinetics of AMX achieved a better fit by the pseudo-second-order model than the pseudo-first-order model. The electrostatic and nonelectrostatic interactions between the zwitterionic form of AMX and the positively charged CeO2@SiO2 surface were controlled by adsorption. The effects of different organics such as humic acid, ionic surfactants, and pharmaceutical substances on AMX removal using CeO2@SiO2 were also thoroughly investigated. The high AMX removal efficiencies of about 75% after four regenerations and about 70% from an actual water sample demonstrate that CeO2@SiO2-based rice husk is a hybrid nanomaterial for antibiotic removal from water environments.
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Affiliation(s)
- Tien-Duc Pham
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi-19 Le Thanh Tong, Hoan Kiem, Hanoi 100000, Vietnam
| | - Thi-Mai-Anh Le
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi-19 Le Thanh Tong, Hoan Kiem, Hanoi 100000, Vietnam
| | - Thi-My-Quynh Pham
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi-19 Le Thanh Tong, Hoan Kiem, Hanoi 100000, Vietnam
| | - Viet-Huy Dang
- High School of Education Sciences, University of Education, Vietnam National University, Hanoi; Kieu Mai, Phuc Dien, Bac Tu Liem, Hanoi 100000, Vietnam
| | - Khanh-Linh Vu
- High School of Education Sciences, University of Education, Vietnam National University, Hanoi; Kieu Mai, Phuc Dien, Bac Tu Liem, Hanoi 100000, Vietnam
| | - Trung-Kien Tran
- Hanoi-Amsterdam High School for the Gifted, Hoang Minh Giam, Trung Hoa, Cau Giay, Hanoi 100000, Vietnam
| | - Thu-Ha Hoang
- High School of Education Sciences, University of Education, Vietnam National University, Hanoi; Kieu Mai, Phuc Dien, Bac Tu Liem, Hanoi 100000, Vietnam
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11
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Vu TH, Ngo TMV, Duong TTA, Nguyen THL, Mai XT, Pham THN, Le TP, Tran TH. Removal of Tetracycline from Aqueous Solution Using Nanocomposite Based on Polyanion-Modified Laterite Material. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2020; 2020:6623511. [PMID: 33489413 PMCID: PMC7787789 DOI: 10.1155/2020/6623511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/17/2020] [Accepted: 11/30/2020] [Indexed: 05/26/2023]
Abstract
This work investigated the removal of antibiotic tetracycline (TC) from wastewater using nanocomposite material based on laterite modified with polyanion, polystyrene sulfonate (PSS). The effective factors influenced on the TC removal using nanocomposite PSS-modified laterite (NCPML) were optimized and found to be pH 4, solid-liquid ratio 5 mg/mL, and contact time 180 min. The highest removal of TC reached about 88% under the optimum adsorption conditions. The adsorption isotherm and kinetics of TC adsorption onto NCPML were in good agreement with the Langmuir and pseudo-second-order models, respectively. The characteristics of the NCPML material before and after TC adsorption were examined by zeta (ζ) potential measurements, Brunauer-Emmett-Teller (BET) method, and Fourier transform infrared spectroscopy (FT-IR). The TC adsorption onto NCPML was induced by electrostatic interaction, hydrogen bonding, and diffusion interaction. The TC removal from wastewater was approximately 94% while efficiency still reached 66% after five regenerations. Our research reveals that NCPML is a high-performance adsorbent for TC removal from wastewater.
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Affiliation(s)
- Thi Hau Vu
- Thai Nguyen University of Education, Thai Nguyen University, 20 Luong Ngoc Quyen, Quang Trung, Thai Nguyen, Vietnam
| | - Thi Mai Viet Ngo
- Thai Nguyen University of Education, Thai Nguyen University, 20 Luong Ngoc Quyen, Quang Trung, Thai Nguyen, Vietnam
| | - Thi Tu Anh Duong
- Thai Nguyen University of Education, Thai Nguyen University, 20 Luong Ngoc Quyen, Quang Trung, Thai Nguyen, Vietnam
| | - Thi Hien Lan Nguyen
- Thai Nguyen University of Education, Thai Nguyen University, 20 Luong Ngoc Quyen, Quang Trung, Thai Nguyen, Vietnam
| | - Xuan Truong Mai
- Thai Nguyen University of Education, Thai Nguyen University, 20 Luong Ngoc Quyen, Quang Trung, Thai Nguyen, Vietnam
| | - Thi Hong Nguyet Pham
- Thai Nguyen University of Education, Thai Nguyen University, 20 Luong Ngoc Quyen, Quang Trung, Thai Nguyen, Vietnam
| | - Thi Phuong Le
- Thai Nguyen University of Education, Thai Nguyen University, 20 Luong Ngoc Quyen, Quang Trung, Thai Nguyen, Vietnam
| | - Thi Hue Tran
- Thai Nguyen University of Education, Thai Nguyen University, 20 Luong Ngoc Quyen, Quang Trung, Thai Nguyen, Vietnam
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12
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Kobayashi M. An analysis on electrophoretic mobility of hydrophobic polystyrene particles with low surface charge density: effect of hydrodynamic slip. Colloid Polym Sci 2020. [DOI: 10.1007/s00396-020-04716-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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13
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Strength of Flocs Formed by the Complexation of Lysozyme with Leonardite Humic Acid. Polymers (Basel) 2020; 12:polym12081770. [PMID: 32784682 PMCID: PMC7463964 DOI: 10.3390/polym12081770] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/02/2020] [Accepted: 08/05/2020] [Indexed: 11/23/2022] Open
Abstract
Aggregation and aggregates properties of natural organic and nanosized macromolecules such as humic substances and proteins are crucial to explore so-called colloid-mediated transport and the fate of substances in soil and water environments. Therefore, the aggregation and dispersion, charging, and floc strength of lysozyme (LSZ)–leonardite humic acid (LHA) flocs were experimentally investigated. The experiments were performed in different salt concentrations and LSZ to LHA mass ratios as a function of pH. We obtained the stronger flocs at pH 4.4, where the isoelectric point (IEP) of the complex with the mass ratio 2.5 was confirmed. Thus, the aggregation of LSZ–LHA flocs is mainly caused by charge neutralization. We obtained the floc strength of 4.7 nN around IEP at low salt concentration of 3 mM, which was stronger than 2.8 nN in high salt concentration of 50 mM. The effect of salt concentration can be rationalized by charge-patch attraction at low salt concentration. With increasing mass ratio, the IEP shifted to higher pH. This is due to the increase in positive charge from LSZ in the mixture. The effect of the LSZ to LHA mass ratio on the maximum strength was weak in the range studied.
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14
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Huang Y, Kobayashi M. Direct Observation of Relaxation of Aqueous Shake-Gel Consisting of Silica Nanoparticles and Polyethylene Oxide. Polymers (Basel) 2020; 12:polym12051141. [PMID: 32429469 PMCID: PMC7285087 DOI: 10.3390/polym12051141] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/14/2020] [Accepted: 05/15/2020] [Indexed: 11/23/2022] Open
Abstract
Controlling the rheological property of suspensions consisting of colloidal particles and polymers is necessary in industry. Especially, gels induced by shear (shake-gel) are interesting phenomena in rheological field. To gain insight into the shake-gel phenomena of the aqueous suspensions of silica nanoparticles and poly(ethylene oxide) (PEO) and its temporal change, we observed the state transition and measured the viscosity of the silica-PEO suspensions. Our results showed that PEO dose, pH, and molecular weight of PEO influence the state of suspension greatly, and revealed the differences of the suspension states, namely, cloudy, permanent gel, shake-gel, and high viscosity sol. We found that the relaxation time from shake-gel to flowable sol increases to the maximum and decreases again with increasing PEO dose. Shake-gels at pH 8.4 relaxed more slowly than at pH 9.4, and shake-gel did not form at pH above 10 in most of cases, indicating high pH inhibits the formation of shake-gels. PEO of molecular weight of 1000 and 4000 kDa easily bonds more silica nanoparticles by bridging and results in the formation of gels with more stable polymer networks. PEO of molecular weight of 1000 and 4000 kDa also led to longer relaxation time of the silica-PEO suspensions from gel to sol.
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Affiliation(s)
- Yi Huang
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennoudai, Tsukuba, Ibaraki 305-8572, Japan;
| | - Motoyoshi Kobayashi
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennoudai, Tsukuba, Ibaraki 305-8572, Japan
- Correspondence:
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15
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Pham TD, Pham TT, Phan MN, Ngo TMV, Dang VD, Vu CM. Adsorption characteristics of anionic surfactant onto laterite soil with differently charged surfaces and application for cationic dye removal. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112456] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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16
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Pham TD, Bui TT, Trang Truong TT, Hoang TH, Le TS, Duong VD, Yamaguchi A, Kobayashi M, Adachi Y. Adsorption characteristics of beta-lactam cefixime onto nanosilica fabricated from rice HUSK with surface modification by polyelectrolyte. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2019.111981] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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17
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Adsorptive Removal of Antibiotic Ciprofloxacin from Aqueous Solution Using Protein-Modified Nanosilica. Polymers (Basel) 2020; 12:polym12010057. [PMID: 31906267 PMCID: PMC7023575 DOI: 10.3390/polym12010057] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 12/19/2019] [Accepted: 12/20/2019] [Indexed: 12/02/2022] Open
Abstract
The present study aims to investigate adsorptive removal of molecular ciprofloxacin using protein-modified nanosilica (ProMNS). Protein was successfully extracted from Moringa seeds while nanosilica was synthesized from rice husk. Fourier-transform infrared (FTIR), ultraviolet visible (UV-Vis) and high-performance liquid chromatography (HPLC) were used to evaluate the characterization of protein. Adsorption of protein onto nanosilica at different pH and ionic strength was thoroughly studied to modify nanosilica surface. The removal efficiency of antibiotic ciprofloxacin (CFX) increased from 56.84% to 89.86% after surface modification with protein. Effective conditions for CFX removal using ProMNS were systematically optimized and found to be pH 7.0, adsorption time 90 min, adsorbent dosage 10 mg/mL, and ionic strength 1 mM KCl. A two-step model was successfully used to fit the adsorption isotherms of CFX onto ProMNS at different ionic strength while a pseudo-second-order model could fit adsorption kinetic of CFX onto ProMNS very well. Maximum adsorption capacity was very high that reached to 85 mg/g. Adsorption of CFX onto ProMNS decreased with increasing KCl concentration, suggesting that adsorption of CFX onto ProMNS is mainly controlled by electrostatic attraction between positively charged ProMNS surface and anionic species of CFX. Adsorption mechanisms of CFX onto ProMNS were discussed in detail based on adsorption isotherms, the change in surface charge by zeta potentail and the change in functional groups by FT-IR. The removal of CFX after three regenerations was greater than 73% while CFX removal from an actual hospital wastewater using ProMNS reached to 70%. Our results suggest that ProMNS is a new and eco-friendly adsorbent to remove antibiotics from aqueous solutions.
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18
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Yamaguchi A, Kobayashi M, Adachi Y. Yield stress of mixed suspension of silica particles and lysozymes: The effect of zeta potential and adsorbed amount. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.123575] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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19
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The effect of monovalent anion species on the aggregation and charging of allophane clay nanoparticles. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.05.054] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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20
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Yu M, Du N, Li H, Hou W. Understanding Li-Al-CO3 layered double hydroxides. (II) Interface electrochemical properties. J Colloid Interface Sci 2019; 547:217-223. [DOI: 10.1016/j.jcis.2019.03.100] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 03/28/2019] [Accepted: 03/29/2019] [Indexed: 10/27/2022]
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21
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22
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Hristova SH, Zhivkov AM. Electrooptical determination of the isoelectric point of globular proteins: Cytochrome c adsorbed on montmorillonite nanoplates. Colloids Surf B Biointerfaces 2019; 176:480-487. [DOI: 10.1016/j.colsurfb.2018.12.069] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 12/20/2018] [Accepted: 12/29/2018] [Indexed: 01/15/2023]
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23
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Investigation about validity of the Derjaguin approximation for electrostatic interactions for a sphere-sphere system. Colloid Polym Sci 2019. [DOI: 10.1007/s00396-019-04469-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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24
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Yu M, Hou W. Predicting Points of Zero Net Charge of Layered Double Hydroxides. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:12619-12624. [PMID: 30265006 DOI: 10.1021/acs.langmuir.8b02469] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Many models such as electrostatic and crystallographic models have been developed to predict the point of zero net charge (PZNC) of (hydr)oxides without structural charges. Nevertheless, there is still a lack of feasible models for the prediction of the PZNC of structurally charged (hydr)oxides such as layered double hydroxides (LDHs), a large class of lamellar inorganic materials possessing positive structural charges. Herein, a modified electrostatic model is proposed by taking the structural charge (σst) and the Pauling's electrostatic valence principle into account, to correlate the PZNC with the characteristic physical constants of (hydr)oxides. The new model suggests that the PZNC of structurally charged (hydr)oxides is proportional to their σst, which was confirmed by the PZNC data of 28 LDH samples. The model can be used to describe or predict the PZNC of LDHs and also may provide guidance for the designed synthesis and application of LDH materials.
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Affiliation(s)
- Miao Yu
- Key Laboratory for Colloid and Interface Chemistry (Ministry of Education) , Shandong University , Jinan 250100 , P. R. China
| | - Wanguo Hou
- Key Laboratory for Colloid and Interface Chemistry (Ministry of Education) , Shandong University , Jinan 250100 , P. R. China
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25
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Zoukrami F, Haddaoui N, Sclavons M, Devaux J, Vanzeveren C. Rheological properties and thermal stability of compatibilized polypropylene/untreated silica composites prepared by water injection extrusion process. Polym Bull (Berl) 2018. [DOI: 10.1007/s00289-018-2344-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Adsorption of Polyelectrolyte onto Nanosilica Synthesized from Rice Husk: Characteristics, Mechanisms, and Application for Antibiotic Removal. Polymers (Basel) 2018; 10:polym10020220. [PMID: 30966256 PMCID: PMC6415144 DOI: 10.3390/polym10020220] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/12/2018] [Accepted: 02/22/2018] [Indexed: 11/17/2022] Open
Abstract
Adsorption of the polyelectrolyte polydiallyldimethylammonium chloride (PDADMAC) onto nanosilica (SiO2) fabricated from rice husk was studied in this work. Nanosilica was characterized by X-ray diffraction, Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Adsorption of PDADMAC onto SiO2 increased with increasing pH because the negative charge of SiO2 is higher at high pH. Adsorption isotherms of PDADMAC onto silica at different KCl concentrations were fitted well by a two-step adsorption model. Adsorption mechanisms of PDADMAC onto SiO2 are discussed on the basis of surface charge change, evaluation by ζ potential, surface modification by FTIR measurements, and the adsorption isotherm. The application of PDADMAC adsorption onto SiO2 to remove amoxicillin antibiotic (AMX) was also studied. Experimental conditions such as contact time, pH, and adsorbent dosage for removal of AMX using SiO2 modified with PDADMAC were systematically optimized and found to be 180 min, pH 10, and 10 mg/mL, respectively. The removal efficiency of AMX using PDADMAC-modified SiO2 increased significantly from 19.1% to 92.3% under optimum adsorptive conditions. We indicate that PDADMAC-modified SiO2 rice husk is a novel adsorbent for removal of antibiotics from aqueous solution.
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