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1.
J Mater Chem B ; 11(40): 9597-9629, 2023 10 18.
Article in English | MEDLINE | ID: mdl-37740402

ABSTRACT

Polyesters based on polyols have emerged as promising biomaterials for various biomedical applications, such as tissue engineering, drug delivery systems, and regenerative medicine, due to their biocompatibility, biodegradability, and versatile physicochemical properties. This review article provides an overview of the synthesis methods, performance, and biodegradation mechanisms of polyol-based polyesters, highlighting their potential for use in a wide range of biomedical applications. The synthesis techniques, such as simple polycondensation and enzymatic polymerization, allow for the fine-tuning of polyester structure and molecular weight, thereby enabling the tailoring of material properties to specific application requirements. The physicochemical properties of polyol-based polyesters, such as hydrophilicity, crystallinity, and mechanical properties, can be altered by incorporating different polyols. The article highlights the influence of various factors, such as molecular weight, crosslinking density, and degradation medium, on the biodegradation behavior of these materials, and the importance of understanding these factors for controlling degradation rates. Future research directions include the development of novel polyesters with improved properties, optimization of degradation rates, and exploration of advanced processing techniques for fabricating scaffolds and drug delivery systems. Overall, polyol-based polyesters hold significant potential in the field of biomedical applications, paving the way for groundbreaking advancements and innovative solutions that could revolutionize patient care and treatment outcomes.


Subject(s)
Polyesters , Polymers , Humans , Polyesters/chemistry , Polymers/chemistry , Biocompatible Materials/chemistry , Biodegradation, Environmental
2.
J Contam Hydrol ; 249: 104048, 2022 08.
Article in English | MEDLINE | ID: mdl-35834911

ABSTRACT

In this study, the adsorption of benzoic acid and phenols in the aqueous phase by MOF-Cu adsorbent was investigated. A high-performance liquid chromatography (HPLC) device was used to analyze the concentration of contaminants in the solution. Three isotherms, Freundlich, Langmuir, and Temkin were performed for adsorption of Benzoic Acid (BA) and Phenol contaminants. Correlation factor for adsorption isotherms were fitted into Langmuir aqueous BA and Phenol would be 99.89 and 99.98%, respectively. The equilibrium adsorption capacity MOF-Cu of BA and Phenol is 636.73 and 524.42 mg/g, respectively. In this study, high contaminant adsorption with π-π interaction and hydrogen bonding leads to the high capacity of MOFCu. In addition, the increase in adsorption capacity of benzoic acid is due to the electronegative property of oxygen in the carbonyl group and the similarity of the carboxylic acid functional group with the adsorbent. The result shows, that at initial time adsorption, has been a non-linear trend. In addition, the first-order kinetic model is not a suitable option for fitting the experimental data of adsorption kinetics and the adsorption kinetics of BA and Phenol is very well compatible with the semi-second order with the correlation Factor being 99.7 and 99.78, respectively. Also, the equilibrium adsorption capacity in pseudo-second order kinetic for BA and Phenol is 613.5 and 523.56 mg/g respectively.


Subject(s)
Metal-Organic Frameworks , Water Pollutants, Chemical , Adsorption , Benzoic Acid/analysis , Hydrogen-Ion Concentration , Kinetics , Phenol/analysis , Phenol/chemistry , Phenols/analysis , Phenols/chemistry , Thermodynamics , Wastewater/chemistry , Water/analysis , Water Pollutants, Chemical/analysis
3.
Membranes (Basel) ; 10(10)2020 Oct 14.
Article in English | MEDLINE | ID: mdl-33066362

ABSTRACT

Nowadays, carbon nano (CN) structures and specifically carbon nanotubes (CNTs), because of the nanotube's nanoscale shape, are widely used in carrier and separation applications. The conjugation of CNTs with polysaccharide, proteins, drugs, and magnetic nanoparticles provides a chance for smart targeting and trajectory manipulation, which are used in the crucial field of life science applications, including for cancer disease diagnostics and treatments. Providing an optimal procedure for delivering a drug to a specific area based on mathematical criteria is key in systemic delivery design. Trajectory guidance and applied force control are the main parameters affected by systemic delivery. Moreover, a better understanding of the tissue parameters and cell membrane molecular behaviour are other factors that can be indirectly affected by the targeted delivery. Both sides are an essential part of successful targeting. The lung is one of the challenging organs for drug delivery inside the human body. It has a large surface area with a thin epithelium layer. A few severe diseases directly involve human lung cells, and optimal and successful drug delivery to the lung for the treatment procedure is vital. In this paper, we studied functionalized CNTs' targeted delivery via crossing through the lung cell membrane. Molecular dynamics (MD) software simulated all the interaction forces. Mathematical modelling of the cell membrane and proposed delivery system based on the relation of velocity and force has been considered. Dynamics equations for CNTs were defined in the time and frequency domain using control theory methods. The proposed delivery system consists of two main parts: crossing through the cell membrane and targeting inside the cell. For both steps, a mathematical model and a proper magnetic field profile have been proposed. The designed system provides criteria for crossing through the cell membrane within 30 s to 5 min and a translocation profile of 1 to 100 Å.

4.
Environ Sci Pollut Res Int ; 27(32): 40618-40632, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32671703

ABSTRACT

A new type of honeycomb structured UiO-66 metal-organic frameworks (MOF) was synthesized and amino functionalized followed by employing them to prepare mixed matrix membranes (MMM). The influences of dimethylformamide (DMF) and H2O/ethanol (70/30 wt.%) blend were firstly investigated on morphology, structure, and CO2/CH4 separation efficiency of Pebax®1657 membranes. Based on the transmission electron microscopy (TEM) analysis, the synthesized MOF has 15 nm in diameter. DMF led to the formation of a more crystalline (based on X-ray diffraction (XRD) analysis) and more porous structure. Higher CO2 permeability and CO2/CH4 selectivity were observed as DMF was employed to fabricate neat membranes. Scanning electron microscopy (SEM) exhibited MOF agglomeration as the UiO-66 was used while the nanoparticle dispersion was enhanced when UiO-66-NH2 was exploited. Fourier transform infrared spectroscopy (FTIR) confirmed the successful MOF incorporation into the MMMs. Ultimately, the gas separation experiments showed that CO2 permeability was enhanced compared to the neat membrane by 44.7% and 49.4% as 10 wt.% UiO-66 and UiO-66-NH2 were used, respectively. Moreover, the Pebax®1657-UiO-66-NH2 MMMs exhibited 71.7% and 34.5% improvement in selectivity of CO2/N2 and CO2/CH4, respectively, owing to enhancing CO2-OH interactions while the CO2/O2 was declined by 8.8%.


Subject(s)
Metal-Organic Frameworks , Nanoparticles , Carbon Dioxide , Porosity , Spectroscopy, Fourier Transform Infrared
5.
Environ Sci Pollut Res Int ; 25(23): 22889-22902, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29855888

ABSTRACT

The main purpose of this paper is to investigate how to optimize gasoline in order to reduce the emitted pollutants caused by combustion, while the torque and power of the engine reach the maximum capabilities. To optimize gasoline formulation, an ethanol and magnesium oxide (MgO) or cerium oxide (CeO2) mixture was added to gasoline. This study explores the role of main variables such as type of metal nanoparticle additive, engine speed, and throttle on engine performance and exhaust gas emissions through the modeling and optimization methods. Experimental design conducted through the implementation of D-optimal design, taking into account the three main parameters. To review the efficiency of this novel fuel, it was tested by a four-stroke engine connected to a dynamometer and an analyzer, under different controlled environments: speeds of 1500, 2000, 2500, and 3000 rpm at both half and full throttle conditions. The analyzed data are the power and torque of the engine, the amount of emitted CO, CO2, HC, and NOx, the octane index, and the viscosity. The analyzed data were calculated and turned into models. Applying the models to data (the optimization process), close correlation between predicted and actual outcomes was found, highlighting the validity of the work. A secondary finding is that the CeO2 mixture used at higher speeds and throttles produces less emissions, while lower speeds and throttles using the MgO mixture produce less emissions.


Subject(s)
Cerium/chemistry , Gasoline , Magnesium Oxide/chemistry , Metal Nanoparticles/chemistry , Vehicle Emissions/analysis , Air Pollutants/chemistry , Carbon Dioxide/analysis , Carbon Monoxide/analysis , Equipment Design , Ethanol/chemistry , Models, Theoretical , Octanes/chemistry
6.
J Membr Biol ; 250(6): 651-661, 2017 12.
Article in English | MEDLINE | ID: mdl-29127488

ABSTRACT

In the present work, vertically aligned carbon nanotube (VA-CNT) sheets were synthesized via pyrolysis of polybenzimidazole (PBI)-Kapton inside the pores of anodized aluminum oxide (AAO). The synthesized VA-CNT sheets were then evaluated for the desalination of salty water. The results indicated that the VA-CNT sheets were effective for application as an adsorbent for desalination of salty water due to their high adsorption capacity, with no loss of CNTs in the treated water. This study explored the impact of operating time and temperature on liquid adsorption performance through optimization and modeling methods. An empirical model was developed through the evolution of a full factorial design process which considered two significant factors for enhanced antibacterial efficiency and adsorption uptake. The highest antibacterial efficiency was achieved with carbon precursors synthesized at a higher temperature. However, optimal values were obtained for both antibacterial efficiency and adsorption uptake (NaCl) with a combination of CNT membranes. The best conditions for such a membrane were 800 °C and 18 min. Under these conditions, antibacterial efficiency, contact angle, carbon content, adsorption uptake (NaCl = 10,000) and adsorption uptake (NaCl = 20,000) were 90.079, 1.69256, 75.213, 76.2352 and 0.997, respectively.


Subject(s)
Nanotubes, Carbon/chemistry , Water Purification/methods , Adsorption , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Temperature
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