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hydrogel-nanocomposites
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Adsorption characteristics of malachite green dye onto novel kappa-carrageenan-g-polyacrylic acid/TiO2-NH2 hydrogel nanocomposite
, Article Journal of the Iranian Chemical Society ; Volume 11, Issue 4 , August 2014 , Pages 1057-1065 ; Doulabi, M ; Doroudian, M ; Sharif University of Technology
Abstract
Batch adsorption experiments were carried out for the removal of malachite green (MG) cationic dye from aqueous solution using novel hydrogel nanocomposite that was prepared by graft copolymerization of acrylic acid (AA) onto kappa-carrageenan (κC) biopolymer in the presence of a crosslinking agent, a free radical initiator and aminosilica-functionalized TiO2 nanoparticles (κC-g-PAA/TiO2-NH2). The factors influencing adsorption capacity of the adsorbents such as initial pH value (pH0) of the dye solutions, TiO2-NH2 content (wt%), initial concentration of the dye, amount of adsorbents, and temperature were investigated. The adsorption capacity of hydrogel nanocomposite for MG was compared...
Swelling and mechanical behavior of nanoclay reinforced hydrogel: single network vs. full interpenetrating polymer network
, Article Polymer Bulletin ; Volume 72, Issue 7 , March , 2015 , Pages 1663-1681 ; 01700839 (ISSN) ; Bagheri, R ; Kabiri, K ; Sharif University of Technology
Springer Verlag
2015
Abstract
Despite the various uses of hydrogels, one of their weaknesses is the poor gel strength. To overcome this restriction, the current study has focused on simultaneously employing an interpenetrating polymer network (IPN) structure and nanocomposite hydrogels. Through this approach, the influence of nanofiller in the single network and IPN hydrogel properties was also studied in detail. For this purpose, a novel full interpenetrating polymer network (IPN) hydrogel nanocomposite based on 2-acrylamido-2-methylpropane sulfonic acid (AMPS)/acrylic acid (AA)–sodium acrylate (AANa) was synthesized in two steps through a facile solution polymerization with incorporation of modified bentonite (MBE) as...
Design and Synthesis of Heterogeneous Nanocatalysts Based on Immobilized Metals on Polymeric Substrates and their Applications in Organic Reactions
, Ph.D. Dissertation Sharif University of Technology ; Pourjavadi, Ali (Supervisor)
Abstract
Today, catalysts have shown the growing applications in chemical industries especially for drug synthesis. Using immobilized heterogeneous catalysts is a sensible way to benefit from advantages of both heterogeneous and homogeneous catalysts. In this regards, homogeneous catalysts are immobilized on to a solid support through various methods. However, low loading amount of homogenous part and subsequently insufficient catalytic activity are main limitations of immobilized heterogeneous catalysts. For this reason, polymeric supports have been introduced to immobilize metal ions or nanoparticles. These polymeric supports not only possess advantages such as anti-corrosive properties, simple...
3D Stem Cell Culture and Differentiation Using Alginate Hydrogel Scaffolds Incorporated with Silicon-Based Nanoparticles
, Ph.D. Dissertation Sharif University of Technology ; Yaghmaei, Soheila (Supervisor) ; Arpanaei, Ayyoob (Co-Supervisor) ; Dolatshahi Pirouz, Alireza (Co-Supervisor)
Abstract
Bone is one of the most vital parts of the body for almost any functional movement. Due to its many involved diseases, traumas and injuries, bone maintenance and regeneration are of high importance. Engineering and design of complex tissues, with impeccable mimicry of the native ones, are always accounted as the solution to dysfunction of body organs due to aging, various diseases, etc. However, the inability to complete mimicry of the native tissue architecture and cell microenvironment are the main barriers to functional tissue regeneration. In this project, in order to design a suitable scaffold for bone regeneration, hydrogel nanocomposites with polysaccharide basis were developed by...
Biomimetic ultraflexible piezoresistive flow sensor based on graphene nanosheets and PVA hydrogel
, Article Advanced Materials Technologies ; 2021 ; 2365709X (ISSN) ; Moradi, H ; Wu, S ; Han, Z. J ; Razmjou, A ; Asadnia, M ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Flow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze-like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting...
Biomimetic ultraflexible piezoresistive flow sensor based on graphene nanosheets and PVA hydrogel
, Article Advanced Materials Technologies ; 2021 ; 2365709X (ISSN) ; Moradi, H ; Wu, S ; Han, Z. J ; Razmjou, A ; Asadnia, M ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Flow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze-like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting...
Biomimetic ultraflexible piezoresistive flow sensor based on graphene nanosheets and pva hydrogel
, Article Advanced Materials Technologies ; Volume 7, Issue 1 , 2022 ; 2365709X (ISSN) ; Moradi, H ; Wu, S ; Han, Z. J ; Razmjou, A ; Asadnia, M ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Flow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze-like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting...
Synthesis and in Vitro/in Vivo Evaluation of Bioprinted and Core-Shell Systems Containing Proteoglycan Nanoparticle and Growth Factor for Skin Tissue Regeneration
, Ph.D. Dissertation Sharif University of Technology ; Simchi, Abdolreza (Supervisor) ; Shokrgozar, Mohammad Ali (Supervisor) ; Tamjid, Elnaz (Co-Supervisor)
Abstract
Tissue engineering has the potential to revolutionize our health care system. Conceptually, lost or malfunctioning tissues will be replaced by man-made biological substitutes to restore, maintain, or improve function. Tissue engineering has already shown great promise to contribute to treatments of a myriad of diseases including osteoarthritis, cancer, diabetes, skin burns, cardiovascular conditions and various traumatic injuries. Tissue engineering is a highly multidisciplinary discipline that demands integration of knowledge, tools and skills from biology, chemistry, engineering and medicine. Integrating nano- and microtechnologies into clinically sized implants represents a major...
PVP-PEG-BaTiO3 Hydrogels, Synthesis and Characterization for Medical Applications
, M.Sc. Thesis Sharif University of Technology ; Frounchi, Masoud (Supervisor) ; Dadbin, Susan (Supervisor)
Abstract
Today, hydrogels have various biomedical applications as three-dimensional networks with the ability to absorb and retain water and biological fluids. This study aimed to prepare nanocomposite hydrogels from polyvinyl pyrrolidone, polyethylene glycol, and barium titanate nanoparticles. Gamma radiation at irradiation doses of 25 and 35 kGy was used as the hydrogel's crosslinking agent. The effects of gamma irradiation dose, percentage of polyethylene glycol, and barium titanate composition on the swelling ratio and gel content were investigated. It was observed that the amount of gel content with the addition of polyethylene glycol and barium titanate nanoparticles reduces the gel content and...
Design and Manufacture of Polymeric Nanocomposite in Order to Control the Production and Migration of Sand in Reservoirs
, Ph.D. Dissertation Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Baghban Salehi, Mahsa (Supervisor)
Abstract
Sand production from oil reservoirs leads to various problems, such as well productivity reduction, operating equipment corrosion, and increased production costs. Therefore, controlling sand production in unconsolidated reservoirs is crucial for operating companies. Chemical injection into the formation in order to strengthen and reduce sand production is one of the most important methods of sand control. In this study, a hydrogel nanocomposite was designed and its effectiveness in sand control was investigated. Various tests were carried out to define and assess its efficacy, as follows: Morphological tests demonstrated the creation of a dense, homogeneous, and porous structure. Structural...
Combinatorial screening of nanoclay-reinforced hydrogels: a glimpse of the "holy grail" in orthopedic stem cell therapy?
, Article ACS Applied Materials and Interfaces ; Volume 10, Issue 41 , 2018 , Pages 34924-34941 ; 19448244 (ISSN) ; Thakur, A ; Taebnia, N ; Kadumudi, F. B ; Shahbazi, M. A ; Pierchala, M. K ; Mohanty, S ; Orive, G ; Andresen, T. L ; Foldager, C. B ; Yaghmaei, S ; Arpanaei, A ; Gaharwar, A. K ; Mehrali, M ; Dolatshahi Pirouz, A ; Sharif University of Technology
American Chemical Society
2018
Abstract
Despite the promise of hydrogel-based stem cell therapies in orthopedics, a significant need still exists for the development of injectable microenvironments capable of utilizing the regenerative potential of donor cells. Indeed, the quest for biomaterials that can direct stem cells into bone without the need of external factors has been the "Holy Grail" in orthopedic stem cell therapy for decades. To address this challenge, we have utilized a combinatorial approach to screen over 63 nanoengineered hydrogels made from alginate, hyaluronic acid, and two-dimensional nanoclays. Out of these combinations, we have identified a biomaterial that can promote osteogenesis in the absence of...
Salep-g-poly(sodium acrylate)/alumina as an environmental-sensitive biopolymer superabsorbent composite: Synthesis and investigation of its swelling behavior
, Article Advances in Polymer Technology ; Volume 31, Issue 1 , 2012 , Pages 41-51 ; 07306679 (ISSN) ; Pourjavadi, A ; Soleyman, R ; Ghavami, S ; Sharif University of Technology
Abstract
A novel kind of a biopolymer-based superabsorbent composite, salep-g-poly(sodium acrylate)/alumina, was prepared from salep, sodium acrylate, and alumina by aqueous polymerization, using N,N'-methylenebisacrylamide (MBA) as a cross-linker and ammonium persulfate (APS) as an initiator. The reaction parameters [i.e., acrylic acid (AA), MBA, APS amounts, and neutralization percentage of AA as well as alumina/salep weight ratio] affecting the water absorbency of the hydrogel composite were optimized using systematic method to achieve a composite with high swelling capacity as possible. The swelling behavior of optimum superabsorbent composite was measured in various pH solutions. In addition,...
Hydrogel nanocomposite based on chitosan-g-acrylic acid and modified nanosilica with high adsorption capacity for heavy metal ion removal
, Article Iranian Polymer Journal (English Edition) ; Volume 24, Issue 9 , September , 2015 , Pages 725-734 ; 10261265 (ISSN) ; Mazaheri Tehrani, Z ; Salimi, H ; Banazadeh, A ; Abedini, N ; Sharif University of Technology
Springer-Verlag London Ltd
2015
Abstract
In this study, a novel hybrid hydrogel based on chitosan, acrylic acid and amine-functionalized nanosilica was prepared and characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. This hydrogel nanocomposite was used for removal of Co2+, Cu2+, Pb2+ and Zn2+ ions from aqueous solution. The metal ion adsorption was measured by inductively coupled plasma mass spectrometry. The adsorption behavior showed that the presence of modified nanosilica enhanced the porosity of the hydrogel network and affected its adsorption capacity in response to different parameters such as nanosilica content, metal ion concentration, adsorbent content,...
Structure, swelling and mechanical behavior of a cationic full-IPN hydrogel reinforced with modified nanoclay
, Article Iranian Polymer Journal (English Edition) ; Volume 24, Issue 5 , May , 2015 , Pages 379-388 ; 10261265 (ISSN) ; Bagheri, R ; Kabiri, K ; Sharif University of Technology
Springer-Verlag London Ltd
2015
Abstract
Despite various applications of hydrogels, they have poor gel strength and low resistance against crack propagation which lead to the limitation of their applications. For overcoming this inherent weakness, the current study has focused on the simultaneous utilization of interpenetrating polymer network (IPN) structure and nanocomposite hydrogels. It is known that IPN and nanocomposite gels can improve gel strength. The combination of IPN and nanocomposite structure was developed in hydrogels for improving gel strength. For this purpose, bentonite was successfully modified with a cationic surfactant, (3-methacrylamidopropyl) trimethyl ammonium chloride (MAPTAC), as intercalate, and...
Semi-IPN carrageenan-based nanocomposite hydrogels: Synthesis and swelling behavior
, Article Journal of Applied Polymer Science ; Volume 118, Issue 5 , 2010 , Pages 2989-2997 ; 00218995 (ISSN) ; Marandi, G. B ; Pourjavadi, A ; Kiani, G ; Sharif University of Technology
2010
Abstract
Inclusion of nano-clays into hydrogels is an efficient approach to produce nanocomposite hydrogels. The introduction of nano-clay into hydrogels causes an increase in water absorbency. In the present work, Nanocomposite hydro-gels based on kappa-carrageenan were synthesized using sodium montmorillonite as nano-clay. Acrylamide and meth-ylenebisacrylamide were used as monomer and crosslinker, respectively. The structure of nanocomposite hydrogels was investigated by XRD and SEM techniques. Swelling behavior of nanocomposite hydrogels was studied by varying clay and carrageenan contents as well as methylenebisacrylamide concentration. An optimum swelling capacity was achieved at 12% of sodium...
Both tough and soft double network hydrogel nanocomposite based on o-carboxymethyl chitosan/poly(vinyl alcohol) and graphene oxide: a promising alternative for tissue engineering
, Article Polymer Engineering and Science ; Volume 60, Issue 5 , 2020 , Pages 889-899 ; Mazaheri Tehrani, Z ; Salami, H ; Seidi, F ; Motamedi, A ; Amanzadi, A ; Zayerzadeh, E ; Shabanian, M ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
A reinforced double network (DN) hydrogel as a candidate for skin scaffold was prepared. It consists of O-carboxymethyl chitosan, polyvinyl alcohol, honey, CaCl2, and graphene oxide. The various concentrations of CaCl2, namely, 30, 45, and 60 wt% were investigated. Besides, the GO content was studied as 3, 5, and 10 wt%. The structure of the DN was characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, energy dispersive X-ray and Brunauer-Emmett-Teller were evaluated. The mechanical properties were studied, too. It showed that the DN with 45 wt% CaCl2 was optimized. Also, swelling mechanism was investigated....
An electroconductive, thermosensitive, and injectable chitosan/pluronic/gold-decorated cellulose nanofiber hydrogel as an efficient carrier for regeneration of cardiac tissue
, Article Materials ; Volume 15, Issue 15 , 2022 ; 19961944 (ISSN) ; Maleki Jirsaraei, N ; Simchi, A ; Mohandes, F ; Emami, Z ; Fassina, L ; Naro, F ; Conti, B ; Barbagallo, F ; Sharif University of Technology
MDPI
2022
Abstract
Myocardial infarction is a major cause of death worldwide and remains a social and healthcare burden. Injectable hydrogels with the ability to locally deliver drugs or cells to the damaged area can revolutionize the treatment of heart diseases. Herein, we formulate a thermo-responsive and injectable hydrogel based on conjugated chitosan/poloxamers for cardiac repair. To tailor the mechanical properties and electrical signal transmission, gold nanoparticles (AuNPs) with an average diameter of 50 nm were physically bonded to oxidized bacterial nanocellulose fibers (OBC) and added to the thermosensitive hydrogel at the ratio of 1% w/v. The prepared hydrogels have a porous structure with open...
Green polymer nanocomposites for skin tissue engineering
, Article ACS Applied Bio Materials ; 2022 ; 25766422 (ISSN) ; Shokrani, A ; Jouyandeh, M ; Seidi, F ; Gholami, F ; Kar, S ; Munir, M. T ; Kowalkowska Zedler, D ; Zarrintaj, P ; Rabiee, N ; Saeb, M. R ; Sharif University of Technology
American Chemical Society
2022
Abstract
Fabrication of an appropriate skin scaffold needs to meet several standards related to the mechanical and biological properties. Fully natural/green scaffolds with acceptable biodegradability, biocompatibility, and physiological properties quite often suffer from poor mechanical properties. Therefore, for appropriate skin tissue engineering and to mimic the real functions, we need to use synthetic polymers and/or additives as complements to green polymers. Green nanocomposites (either nanoscale natural macromolecules or biopolymers containing nanoparticles) are a class of scaffolds with acceptable biomedical properties window (drug delivery and cardiac, nerve, bone, cartilage as well as skin...
Piezoelectric behavior of Gamma-radiated nanocomposite hydrogel based on PVP-PEG-BaTiO3
, Article Materials Science and Engineering B: Solid-State Materials for Advanced Technology ; Volume 276 , 2022 ; 09215107 (ISSN) ; Frounchi, M ; Dadbin, S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This study aimed to evaluate the properties of nanocomposite hydrogel (NCH) based on poly (vinyl pyrrolidone) (PVP), poly (ethylene glycol) (PEG), and Barium titanate (BTNPs). Gamma radiation at various doses (25 kGy, 35 kGy) was employed to prepare cross-linked hydrogel. The effect of PVP concentration, PVP/PEG ratio, and BTNPs content, and irradiation dosage on gel content and swelling ratio of synthesized hydrogels were determined. The Flory-Rehner equation was employed to calculate the network parameters. The FTIR results indicate that the chemical structure was deformed through crosslinking PVP macromolecule radicals. The XRD spectra indicated the cubic phase of BTNPs particles and the...
Customizing nano-chitosan for sustainable drug delivery
, Article Journal of Controlled Release ; Volume 350 , 2022 , Pages 175-192 ; 01683659 (ISSN) ; Vahidi, O ; Moghbeli, M ; Ahmadi, S ; Asadnia, M ; Akhavan, O ; Seidi, F ; Rabiee, M ; Saeb, M. R ; Webster, T. J ; Varma, R. S ; Sharifi, E ; Zarrabi, A ; Rabiee, N ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Chitosan is a natural polymer with acceptable biocompatibility, biodegradability, and mechanical stability; hence, it has been widely appraised for drug and gene delivery applications. However, there has been no comprehensive assessment to tailor-make chitosan cross-linkers of various types and functionalities as well as complex chitosan-based semi- and full-interpenetrating networks for drug delivery systems (DDSs). Herein, various fabrication methods developed for chitosan hydrogels are deliberated, including chitosan crosslinking with and without diverse cross-linkers. Tripolyphosphate, genipin and multi-functional aldehydes, carboxylic acids, and epoxides are common cross-linkers used in...