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1.
Heliyon ; 9(2): e13128, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36747553

RESUMEN

Nanotechnology has become an exciting area of research in diverse fields, such as: healthcare, food, agriculture, cosmetics, paints, lubricants, fuel additives and other fields. This review is a novel effort to update the practioneers about the most current developments in the widespread use of green synthesized nanoparticles in medicine. Biosynthesis is widely preferred among different modes of nanoparticle synthesis since they do not require toxic chemical usage and they are environment-friendly. In the green bioprocess, plant, algal, fungal and cyanobacterial extract solutions have been utilized as nucleation/capping agents to develop effective nanomaterials for advanced medical applications. Several metal salts, such as silver, zinc, titanium and other inorganic salts, were utilized to fabricate innovative nanoparticles for healthcare applications. Irrespective of the type of wound, infection in the wound area is a widespread problem. Micro-organisms, the prime reason for wound complications, are gradually gaining resistance against the commonly used antimicrobial drugs. This necessitates the need to generate nanoparticles with efficient antimicrobial potential to keep the pathogenic microbes under control. These nanoparticles can be topically applied as an ointment and also be used by incorporating them into hydrogels, sponges or electrospun nanofibers. The main aim of this review is to highlight the recent advances in the Ag, ZnO and TiO2 nanoparticles with possible wound healing applications, coupled with the bactericidal ability of a green synthesis process.

2.
Int J Biol Macromol ; 242(Pt 2): 124814, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37201889

RESUMEN

Metal nanoparticles have been tremendously utilised, such as; antibacterial and anticancer agents. Although metal nanoparticles exhibits antibacterial and anticancer activity, but the drawback of toxicity on normal cells limits their clinical applications. Therefore, improving the bioactivity of hybrid nanomaterial (HNM) and minimizing toxicity is of paramount importance for biomedical applications. Herein, a facile and simple double precipitation method was used to develop biocompatible and multifunctional HNM from antimicrobial chitosan, curcumin, ZnO and TiO2. In HNM, biomolecules chitosan and curcumin were used to control the toxicity of ZnO and TiO2 and improve their biocidal properties. The cytotxicological properties of the HNM was studied against human breast cancer (MDA-MB-231) and fibroblast (L929) cell lines. The antimicrobial activity of the HNM was examined against Escherichia coli and Staphylococcus aureus bacteria, via the well-diffusion method. In addition, the antioxidant property was evaluated by the radical scavenging method. These findings actively, support the ZTCC HNM potential, as an innovative biocidal agent for applications in the clinical and healthcare sectors.


Asunto(s)
Antiinfecciosos , Quitosano , Curcumina , Nanoestructuras , Óxido de Zinc , Humanos , Curcumina/farmacología , Óxido de Zinc/farmacología , Antibacterianos/farmacología
3.
Int J Biol Macromol ; 212: 561-578, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35643157

RESUMEN

Natural biopolymers have been widely employed as biomaterial ink hydrogels for three-dimensional (3D) extrusion bioprinting in the preparation of the next generation of bioengineering materials for healthcare applications. Alginate is a linear anionic polysaccharide with favourable properties, such as: typical rheological (gelling, viscosifying, and stabilizing dispersions) characteristics, biodegradability and biocompatibility properties. However, in order to improve alginate applicability for practical biomaterial/bio ink for advanced medical applications, it is often modified and functionalized with several polymers and nanomaterials in order to obtain better printability of alginate-based biomaterial/bio ink hydrogels. This review, principally, emphasizes the recent developments and with a comprehensive overview of alginate-based biomaterial/bio ink hydrogels and their biomaterials (3D scaffolds, tissue-like structures with hierarchical vasculatures, mimics of biological, physiological and pathological functionalities) for biomedical applications. It also addresses the significance of alginates, oxidized alginate and their functionalizations (interface) with various materials in order to improve the biomaterial/bio ink properties for 3D extrusion bioprinting applications. Finally, it provides current advances, vital roles and new perspectives of alginate-based materials and their future developments for 3D bioprinting purposes.


Asunto(s)
Alginatos , Bioimpresión , Alginatos/química , Materiales Biocompatibles/química , Bioimpresión/métodos , Hidrogeles/química , Impresión Tridimensional , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
4.
Carbohydr Polym ; 274: 118646, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34702465

RESUMEN

Biocidal activity and biocompatibility of nanomaterials (NMs) are crucial for healthcare applications. This study aims to develop biocidal hybrid NMs with high inhibition rates to control multidrug-resistant bacterial infection compared to conventional antibiotics. Herein, ZnO, chitosan-ZnO (CZnO) and alginate-ZnO (AZnO) NMs were synthesized via a simple one-pot technique. The one-pot process facilitates the efficiency of a chemical reaction whereby a reactant is subjected to successive chemical reactions in just one step. The resulted NMs bio-physicochemical features were analyzed using various analytical methods. The bactericidal and bacteriostatic mechanism of NMs strongly depends on the production of reactive oxygen species in NMs, due to their size, large surface areas, oxygen vacancies, ion release, and diffusion ability. The antibacterial potential of the NMs was tested against methicillin-resistant Staphylococcus aureus. The inhibition zone disclosed that the AZnO possessed an excellent antibacterial activity compared to ZnO and CZnO. Furthermore, toxicity studies revealed that the AZnO demonstrated low toxicity to the HepG2 cell lines. These results confirmed that the AZnO hybrid nanomaterials are promising futuristic biocidal agents suitable for the clinical and healthcare industries.


Asunto(s)
Alginatos , Antibacterianos/farmacología , Quitosano , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Nanoestructuras , Óxido de Zinc , Alginatos/química , Alginatos/farmacología , Quitosano/química , Quitosano/farmacología , Células Hep G2 , Humanos , Nanoestructuras/química , Nanoestructuras/microbiología , Especies Reactivas de Oxígeno/farmacología , Óxido de Zinc/química , Óxido de Zinc/farmacología
5.
Carbohydr Polym ; 259: 117762, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33674015

RESUMEN

Biopolymer-based nanomaterials have been developed as antimicrobial and anticancer agents due to their advanced physical, chemical and biomedical characteristics. Herein, chitosan-copper oxide nanomaterial was, successfully synthesized by a green method. In this process, copper salt was nucleated with Psidium guajava leaves extract in order to form the nanomaterial in the chitosan network. Attenuated total reflection-fourier transform, infrared spectroscopy, X-ray diffraction, Dynamic light scattering, Transmission electron microscope, Field emission scanning electron microscopy/Energy dispersive X-ray analysis, X-ray photoelectron spectroscopy and Photoluminescence spectroscopy techniques were, employed to characterize the synthesized nanomaterial. The average size of the nanomaterial was identified to be ∼52.49 nm with XRD. The antibacterial study of CCuO NM showed higher activity than the commercial amoxicillin against gram-positive (G + ve) (Staphylococcus aureus, Bacillus subtilis) and gram-negative (G-ve) bacteria (Klebsiella pneumonia, Escherichia coli). CCuO NM showed in-vitro anticancer potential against human cervical cancer cells (Hela) with an IC50 concentration of 34.69 µg/mL. Photoluminescence spectrum of CCuO NM showed a green emission (oxygen vacancies) observed at ∼516 nm, which is attributed to the generation of reactive oxygen species (ROS) by the nanomaterial, which is believed, to be responsible for the biocidal (cell death) effects. These results suggested that CCuO is a promising nanomaterial that could be suitable for advanced applications in the healthcare industries.


Asunto(s)
Antibacterianos/química , Antineoplásicos/química , Quitosano/química , Cobre/química , Nanoestructuras/química , Animales , Antibacterianos/farmacología , Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Tecnología Química Verde , Células HeLa , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Nanoestructuras/toxicidad , Tamaño de la Partícula , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Psidium/química , Psidium/metabolismo , Especies Reactivas de Oxígeno/metabolismo
6.
RSC Adv ; 11(49): 30623-30634, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-35479864

RESUMEN

Mishandling of antibiotics often leads to the development of multiple drug resistance (MDR) among microbes, resulting in the failure of infection treatments and putting human health at great risk. As a response, unique nanomaterials with superior bioactivity must be developed to combat bacterial infections. Herein, CeO2-based nanomaterials (NMs) were synthesized by employing cerium(iii) nitrate and selective alkaline ions. Moreover, the influence of alkaline ions on CeO2 was investigated, and their characteristics, viz.: biochemical, structural, and optical properties, were altered. The size of nano Ba-doped CeO2 (BCO) was ∼2.3 nm, relatively smaller than other NMs and the antibacterial potential of CeO2, Mg-doped CeO2 (MCO), Ca-doped CeO2 (CCO), Sr-doped CeO2 (SCO), and Ba-doped CeO2 (BCO) NMs against Streptococcus mutans (S. mutans) and Staphylococcus aureus (S. aureus) strains was assessed. BCO outperformed all NMs in terms of antibacterial efficacy. In addition, achieving the enhanced bioactivity of BCO due to reduced particle size facilitated the easy penetration into the bacterial membrane and the presence of a sizeable interfacial surface. In this study, the minimum quantity of BCO required to achieve the complete inhibition of bacteria was determined to be 1000 µg mL-1 and 1500 µg mL-1 for S. mutans and S. aureus, respectively. The cytotoxicity test with L929 fibroblast cells demonstrated that BCO was less toxic to healthy cells. Furthermore, BCO did not show any toxicity and cell morphological changes in the L929 fibroblast cells, which is similar to the control cell morphology. Overall, the results suggest that nano BCO can be used in biomedical applications, which can potentially help improve human health conditions.

7.
J Hazard Mater ; 411: 124884, 2021 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-33858076

RESUMEN

In the present scenario, the development of eco-friendly multifunctional biocidal substances with low cost and high efficiency, has become the center of focus. This study is, focused on the synthesis of magnesium oxide (MgO) and chitosan-modified magnesium oxide (CMgO) nanoparticles (NPs), via a green precipitation process. In this process, leaves extract of Plumbago zeylanica L was, used as a nucleating agent. The MgO and CMgO NPs exhibit face-centered cubic structures, as confirmed by XRD studies. Morphologically, the FESEM and TEM images showed that the MgO and CMgO NPs were spherical, with an average particle size of ~40±2 and ~37±2 nm, respectively. EDX spectra were used to identify the elemental compositions of the nanoparticles. By using FTIR spectra, the Mg-O stretching frequency of MgO and CMgO NPs were observed at 431 and 435 cm-1, respectively. The photoluminescence (PL) spectra of MgO and CMgO NPs, revealed oxygen vacancies at 499 nm and 519 nm, respectively, due to the active radicals generated, which were responsible for their biocidal activities. The toxicity effects of the nanoparticles developed, on cell viability (antibacterial and anticancer), were measured on the MCF-7 cell line and six different types of gram-negative bacteria. The antibacterial activities of the nanoparticles on: Klebsiella pneumoniae, Escherichia coli, Shigella dysenteriae, Pseudomonas aeruginosa, Proteus vulgaris and Vibrio cholerae bacteria, were studied with the well diffusion method. The MgO and CMgO NPs were tested on breast cancer cell line (MCF-7) via an MTT assay and it proved that CMgO NPs possess higher anticancer properties than MgO NPs. Overall, CMgO NPs showed a higher amount of cytotoxicity for both the bacterial and cancer cells when compared to the MgO NPs. Toxicity studies of fibroblast L929 cells revealed that the CMgO NPs were less harmful to the healthy cells when compared to the MgO NPs. These results suggest that biopolymer chitosan-modified MgO NPs can be used for healthcare industrial applications in order to improve human health conditions.


Asunto(s)
Quitosano , Nanopartículas del Metal , Nanopartículas , Antibacterianos/toxicidad , Quitosano/toxicidad , Bacterias Gramnegativas , Humanos , Óxido de Magnesio/toxicidad , Nanopartículas del Metal/toxicidad , Pruebas de Sensibilidad Microbiana , Nanopartículas/toxicidad , Extractos Vegetales
8.
Carbohydr Polym ; 254: 117302, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33357869

RESUMEN

Currently, special emphasis is being given to the design and fabrication of antibacterial nanocomposite hydrogels for wound dressing applications. Herein, we report the synthesis and characterization of hydroxypropyl methylcellulose (HPMC) reinforced with HPMC capped copper nanoparticles (HCu NPs) based nanocomposite hydrogel films (NHFs). Spherical nanostructures of HCu NPs (∼40 nm) were achieved by facile precipitation technique using ascorbic acid as a nucleating agent and subsequently made their NHFs via solution casting method. Spectral, thermal and structural characteristics of the developed materials were carried out. Antibacterial activity of the resultant NHFs showed the MIC and MBC values of 350 and 1400 µg/mL for S. aureus, and 500 and 2000 µg/mL for E. coli, respectively. These results conveyed that the HCu NPs incorporated HPMC NHFs can be used effectively in antibacterial applications.


Asunto(s)
Antibacterianos/química , Cobre/química , Hidrogeles/química , Derivados de la Hipromelosa/química , Nanopartículas del Metal/química , Metilgalactósidos/química , Nanocompuestos/química , Ácido Ascórbico/química , Vendajes , Precipitación Química , Escherichia coli/efectos de los fármacos , Calor , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Staphylococcus aureus/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos
9.
Int J Biol Macromol ; 165(Pt B): 2711-2720, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33069824

RESUMEN

An environmentally friendly nanocomposite adsorbent composed of two renewable biomaterials, bacterial cellulose (BC) nanofibrils and hydroxyapatite (HA) nanocrystals, was synthetized by an in situ wet chemical precipitation technique, using clam shell biowaste as feedstock. HA nanocrystals embedded in an ultrafine BC network were confirmed and characterized trough different instrumental techniques (SEM, FTIR, XRD, EDS, surface charge and BET analysis), describing its nanostructure, chemical composition and thermal stability. The adsorptive removal of lead ions by the nanocomposite was investigated through batch experiments conducted under different pH, contact times and Pb(II) initial concentrations, proving that the process was highly favorable according to the Langmuir isotherm model (monolayer adsorption) with chemisorption as the main mechanism and kinetic data obeying a nonlinear pseudo-second order kinetic model. The developed nanocomposite showed a strong removal capacity of Pb(II) both in batch experiments (192 mg/g) and packed-bed column systems (188 mg/g), placing this new nanocomposite among top-performing BC-based biomaterials for lead removal.


Asunto(s)
Celulosa/química , Durapatita/química , Plomo/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción/efectos de los fármacos , Plomo/toxicidad , Nanocompuestos/química , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Agua/química , Contaminantes Químicos del Agua/toxicidad , Purificación del Agua/métodos
10.
Int J Biol Macromol ; 164: 963-975, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32707282

RESUMEN

The development of ideal wound dressing materials with excellent characteristics is currently a major demand in wound therapy. In recent years, carboxymethyl cellulose (CMC)-based wound dressing materials have been of immense attraction due to their noble properties, such as: biocompatibility, biodegradability, tissue resembling, low cost and non-toxic. It is used extensively, in a variety of applications in the biomedical and pharmaceutical fields. The hydrophilic nature of CMC, makes it possible to blend and cross-link with other materials, such as: synthetic polymers, natural polymers and inorganic materials and it enables the preparation of innovative wound dressing biomaterials. Hence, this review, focuses on the intrinsic characteristics of CMC-based wound dressing materials, including hydrogels, films, 3D printing, fibres, gauzes and their recent advancements in chronic wound healing.


Asunto(s)
Vendajes , Materiales Biocompatibles/química , Carboximetilcelulosa de Sodio/química , Nanopartículas/química , Polímeros/química , Cicatrización de Heridas , Animales , Celulosa , Humanos , Hidrogeles/química , Control de Infecciones , Ratones , Impresión Tridimensional , Úlcera
11.
Carbohydr Polym ; 236: 116025, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32172843

RESUMEN

Alginate biopolymer has been used in the design and development of several wound dressing materials in order to improve the efficiency of wound healing. Mainly, alginate improves the hydrophilic nature of wound dressing materials in order to create the required moist wound environment, remove wound exudate and increase the speed of skin recovery of the wound. In addition, alginate can easily cross-link with other organic and inorganic materials and they can promote wound healing in clinical applications. This review article addresses the importance of alginates and the roles of derivative polymeric materials in wound dressing biomaterials. Additionally, studies on recent alginate-based wound dressing materials are discussed.


Asunto(s)
Alginatos/química , Materiales Biocompatibles/química , Vendas Hidrocoloidales , Humanos , Hidrogeles/química , Nanopartículas/química , Polímeros/química
12.
Carbohydr Polym ; 249: 116825, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32933672

RESUMEN

As a result of the existence of drug-resistant bacteria and the attendant deficiency of innovative antibiotics, the therapeutic and the clinical sectors are, continually, in search of appropriate multifunctional nanomedicines. Herein, curcumin-chitosan-zinc oxide (CCZ) was successfully synthesized by a one-pot method. Transmission electron micrograph reveals that curcumin and chitosan were layered on a hexagonal ZnO and the particles are sized to ∼48 ±2nm. X-ray diffractogram confirmed the formation of CCZ crystal structure. The photoluminescence spectra of CCZ, shows blue and green emissions at 499 nm and 519 nm, respectively, due to the active radicals generated in the nanomaterial, which are responsible for the associated antimicrobial and anticancer activities. The antibacterial activity of the CCZ, performed against methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), showed a greater antibacterial effect than the commercial amoxicillin. The cytotoxic effect of the CCZ nanomaterial was examined in cultured (MCF-7) human breast cancer cells. An IC50 concentration value of 43.53 µg/mL, was recorded when evaluated after 24 h of CCZ with the MCF-7 cell line. From this study, it is believed that CCZ is a highly promising nanomaterial, which will be suitable for advanced clinical applications.


Asunto(s)
Antibacterianos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Quitosano/química , Curcumina/farmacología , Escherichia coli/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Óxido de Zinc/química , Curcumina/química , Femenino , Humanos , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Nanoestructuras/administración & dosificación , Nanoestructuras/química
13.
Carbohydr Polym ; 236: 116053, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32172868

RESUMEN

A few fruits have short post-harvest life due to high metabolic activity, relatively high water content vulnerability towards microbes and loss of weight during their storage. Carboxymethyl cellulose (CMC)-Guar gum-silver nanocomposite films (CG-Ag0NC) are developed to address these issues. The silver nanoparticles were generated in the CMC-Guar gum matrix through a reduction by Mentha leaves extract. All the films were characterized by UV-vis spectroscopy, FT-IR, TGA, XRD, SEM, TEM, and zeta potential measurements. The antimicrobial activity of CG and CG-Ag0NC was measured by determining their zone inhibition values with ten food pathogenic microbes. The shelf life of CG-Ag0NC films was tested with the model fruit, strawberries, and compared with other packing films. The results are encouraging in terms of freshness, shelf-life and weight loss.


Asunto(s)
Antibacterianos/farmacología , Carboximetilcelulosa de Sodio/química , Galactanos/química , Mananos/química , Nanopartículas del Metal/química , Nanocompuestos/química , Gomas de Plantas/química , Plata/farmacología , Antibacterianos/química , Bacterias/efectos de los fármacos , Embalaje de Alimentos , Conservación de Alimentos , Fragaria , Mentha , Pruebas de Sensibilidad Microbiana , Plata/química , Resistencia a la Tracción
14.
Int J Biol Macromol ; 143: 825-832, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31715225

RESUMEN

Copper nanoparticles were synthesized via precipitation technique using the pseudonatural cationic chitosan biopolymer as a stabilizing agent. The nanoparticles developed were successfully incorporated into the 1:1 ratio of blended chitosan: pluronic F127 polymer solution and made their nanocomposite hydrogels by solution casting method. The formed copper-based nanocomposite hydrogels were characterized by using Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy-energy dispersive spectroscopy and transmission electron microscopy studies. The antimicrobial activity of the fabricated nanocomposite hydrogels was tested via an inhibition zone process against both E. coli (gram-negative) and S. aureus (gram-positive) bacteria. The results conveyed that the copper-embedded chitosan-pluronic\ F127 nanocomposite hydrogels can be used effectively for antimicrobial applications as well as for wound care applications.


Asunto(s)
Antiinfecciosos/química , Antiinfecciosos/farmacología , Quitosano/química , Cobre/química , Nanocompuestos/química , Nanogeles/química , Fenómenos Químicos , Técnicas de Química Sintética , Escherichia coli/efectos de los fármacos , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Nanocompuestos/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Difracción de Rayos X
15.
RSC Adv ; 9(15): 8326-8332, 2019 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-31131098

RESUMEN

Well-defined nanocomposite structures have received significant attention due to their superior combinatorial properties. Rational tuning of the core and shell of the nanostructure(s) can offer potent antibacterial activity. Such advanced core-shell nanocomposite methodologies allow not only the incorporation of antibacterial agents on the shell but also provide its stability and nurture antibacterial activity. Herein, antibiotic zinc oxide-curcumin (ZnO-Cum) core-shell nanoparticles for antibacterial application were synthesised. The ZnO-Cum core-shell nanoparticles were prepared by curcumin nanolayer deposition on zinc oxide nanoparticles via a sonication process. The resulting ZnO-Cum core-shell nanoparticles were spiracle in shape with a ∼45 nm ZnO core and ∼12 nm curcumin shell layer size, respectively, determined by transmission electron microscopy. X-ray diffraction analysis confirmed the formation of a core-shell crystal structure. Additionally, UV-DRS and ATR-FTIR spectral analysis support the existence of ZnO and curcumin in a core-shell nanocomposite. The antibacterial activities of nanoparticles developed were studied against Staphylococcus aureus and Streptococcus pneumoniae and Escherichia coli and Shigella dysenteriae bacterial stains using the diffusion method. A greater inhibition of the growth of Gram positive and negative bacteria was noticed upon treatment with core-shell ZnO and curcumin nanoparticles than the commercial antibiotic amoxicillin which indicates their antibacterial property. The findings of this study provide evidence that the zinc oxide-curcumin core-shell nanoparticles may be highly promising for antibacterial and biomedical applications.

16.
RSC Adv ; 9(40): 22883-22890, 2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-35514475

RESUMEN

Hydroxyapatite (HA) was synthesized by wet chemical precipitation, using clam shell (CS) waste as feedstock. SEM and TEM observation of the produced hydroxyapatite revealed the presence of rod-shaped nanocrystals, while XRD and EDS analyses confirmed the characteristic patterns of hydroxyapatite molecules. This material was subsequently employed as a sorbent for heavy metal removal from aqueous solutions, both in batch and column equilibrium procedures. In batch studies, higher sorption efficiencies were obtained at pH 5, with the highest adsorption capacities of 265, 64, and 55 mg g-1 for Pb(ii), Cd(ii), and Cu(ii), respectively. In addition, an adsorption capacity of 42.5 mg g-1 was determined using a CS-HA packed bed column fed with a solution of Pb(ii). Finally, the breakthrough curve was fitted with Thomas model in order to predict column behavior and scaling up.

17.
Int J Biol Macromol ; 128: 499-508, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30699337

RESUMEN

Chitosan (CH) capped inorganic nanomaterials have been considered as significant antibacterial materials in the clinical field. This work shows the synthesis of two new different antibacterial composite films as a result of the incorporation of CH capped copper oxide (CHCuO) and copper (CHCu) nanoparticles (NPs). Here, CHCuO and CHCu NPs were achieved by a facile chemical reduction of Cu2+ ions using sodium hydroxide and ascorbic acid. TEM analysis revealed the morphology as rod-type nanoflakes for CHCuO and a spherical shape for CHCu NPs with ~7 ±â€¯2 nm size. Antimicrobial activity of the developed materials was studied by the inhibition zone method, against both gram-negative and gram-positive bacteria. The antimicrobial activity revealed that the CHCuO NPs and CHCuO-CH film showed a higher inhibition zone than the other nanomaterials. The results suggested that the synthesized materials can be used in wound dressing applications.


Asunto(s)
Quitosano/química , Cobre/química , Cobre/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Nanopartículas del Metal/química , Nanocompuestos/química , Antibacterianos/química , Antibacterianos/farmacología , Bacillus/efectos de los fármacos , Cápsulas , Escherichia coli/efectos de los fármacos , Propiedades de Superficie , Temperatura
18.
RSC Adv ; 8(32): 18118-18127, 2018 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-29904603

RESUMEN

Herein, two kinds of nano-hydroxyapatite were synthesized from Clam and Magellan shell by wet chemical precipitation method. Mainly, carboxymethyl cellulose/acrylamide/nano-hydroxyapatite composite hydrogels were developed via a free-radical polymerization process and investigated as a sorbent for Acid Blue 113 (AB) from aqueous AB solution. The swelled and kinetic behaviours of hydrogels were investigated using a gravimetric method. The swelling properties of the CMC-AM-hydrogels were influenced by the calcium electrolytes (Ca2+) content in nano-hydroxyapatites. The diffusion coefficient value increased with the increase of nano-hydroxyapatite content in the CMC-AM/nHA-CS (0.22353-0.27681 cm2 s-1) and CMC-AM/nHA-MS (0.22377-0.29737 cm2 s-1) hydrogels. The mechanism of water diffusion was found to be anomalous transport. The CMC-AM/nHA-MS hydrogels showed high AB absorption efficiency and adsorption capacities. These results explained that the nano-hydroxyapatites of Magellan shells based hydrogels are attractive nanocomposite hydrogels for the adsorption of dye in the water purification applications.

19.
Carbohydr Polym ; 164: 186-194, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28325316

RESUMEN

Carboxymethyl cellulose has been used for the design of novel engineered hydrogels in order to obtain effective three-dimensional structures for industrial applications. In this work, dye removal carboxymethyl cellulose-acrylamide-graphene oxide (CMC-AM-GO) hydrogels were prepared by a free-radical polymerization method. The GO was developed by the modified Hummers method. The CMC-AM-GO and GO were characterized by FTIR, XRD and SEM. The swelling and swelling kinetics were calculated using gravimetric process. The kinetic parameter, swelling exponent values [n=0.59-0.7507] explained the fact that the CMC-AM-GO hydrogles have super Case II diffusion transport mechanism. CMCx-AM-GO (x=1-4) and CMC-AM hydrogels were used for removal of Acid Blue-133. The result explains that composite hydrogels significantly removed the acid blue when compared to the neat hydrogel. The maximum AB absorption (185.45mg/g) capacity was found in the case of CMC2-AM-GO hydrogel. Therefore, cellulose-based GO hydrogels can be termed as smart systems for the abstraction of dye in water purification applications.

20.
Mater Sci Eng C Mater Biol Appl ; 70(Pt 1): 85-93, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27770963

RESUMEN

The present investigation describes the development of metal-oxide polymer nanocomposite films from biodegradable poly-ε-caprolactone, disposed poly(ethylene terephthalate) oil bottles monomer and zinc oxide-copper oxide nanoparticles. The terephthalic acid and zinc oxide-copper oxide nanoparticles were synthesized by using a temperature-dependent precipitation technique and double precipitation method, respectively. The terephthalic acid synthesized was confirmed by FTIR analysis and furthermore, it was characterized by thermal analysis. The as-prepared CuO-ZnO nanoparticles structure was confirmed by XRD analysis and its morphology was analyzed by SEM/EDS and TEM. Furthermore, the metal-oxide polymer nanocomposite films have excellent mechanical properties, with tensile strength and modulus better than pure films. The metal-oxide polymer nanocomposite films that were successfully developed show a relatively brighter colour when compared to CuO film. These new metal-oxide polymer nanocomposite films can replace many non-degradable plastics. The new metal-oxide polymer nanocomposite films developed are envisaged to be suitable for use in industrial and domestic packaging applications.


Asunto(s)
Materiales Biocompatibles/química , Metales/química , Nanocompuestos/química , Óxidos/química , Ácidos Ftálicos/química , Poliésteres/química , Polímeros/química , Nanopartículas/química , Nanopartículas/ultraestructura , Polimerizacion , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Estrés Mecánico , Termogravimetría , Difracción de Rayos X
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