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3.
Drug Dev Ind Pharm ; 50(6): 495-510, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38718260

ABSTRACT

OBJECTIVE: The purpose of this study is to investigate the taste masking of Paracetamol granules in the range of 250-850 µm, coated by two nanocomposites prepared from Eudragit® E100, nanozinc oxide, and nanochitosan, respectively, from 1 to 5% by the weight of the granules. METHODS: In this study, Paracetamol granules were coated in several formulas with two different types of nanocomposites (polymeric and mineral) on two sizes of granules to reduce bitter taste and with the FBC method and pH-sensitive polymers (Eudragit® E100). RESULTS: The effect of nanoparticles (Nano zinc oxide and Nanochitosan) on taste-masking Paracetamol was studied with dissolution-coated granules in vitro by simulating in the oral (pH 6.8) range. Based on the results of the studies, the rate of drug release was confirmed by the taste test, and the formulated granule with 5% nano-chitosan (F14) had the best bitter taste mask function of all samples. These results were also confirmed by scanning electron microscopy (SEM) analysis, which showed a smoother and more stable surface than the samples obtained from other formulations. CONCLUSION: In the comparison of the release of two types of nanocomposites in the dissolution test, it was shown that the type B granules of Paracetamol's 5% nano-chitosan-coated granule (F14) were released 99% less than Paracetamol's 5% nano-ZnO-coated granule (F11). and Paracetamol's 1% nano-chitosan-coated granule (F12) was released 91% less than Paracetamol's 1% nano-ZnO-coated granule (F9). The results showed that nano-chitosan-coated granules have better coverage of bitter taste instead of nano-ZnO.


Subject(s)
Acetaminophen , Chitosan , Drug Liberation , Nanocomposites , Taste , Zinc Oxide , Acetaminophen/administration & dosage , Acetaminophen/chemistry , Acetaminophen/pharmacology , Chitosan/chemistry , Taste/drug effects , Zinc Oxide/chemistry , Zinc Oxide/administration & dosage , Zinc Oxide/pharmacology , Nanocomposites/chemistry , Nanoparticles/chemistry , Chemistry, Pharmaceutical/methods , Polymers/chemistry , Solubility , Particle Size , Drug Compounding/methods , Humans , Hydrogen-Ion Concentration , Acrylates
4.
Anesth Pain Med ; 14(1): e142051, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38737591

ABSTRACT

Background: Clavicle fractures account for over one-third of shoulder injuries and up to 3.3% of all fractures in adults. While the majority of these fractures can be managed non-surgically, there are instances where surgical intervention is performed. Regional anesthesia (RA) can be a preferred alternative to general anesthesia (GA) to avoid complications and high costs in this surgery. Moreover, the identification of the most optimal approach for RA remains challenging. Objectives: This study aimed to compare the efficacy of interscalene block (ISB) with and without superficial cervical plexus block (SCPB) as an anesthetic technique for clavicular fracture operation. Methods: This double-blinded, non-inferiority clinical trial was conducted on 120 patients randomly divided into 2 groups: One receiving ISB and the other receiving ISB with SCPB. The primary outcome was defined as the conversion to GA. Various factors were recorded, including surgery duration, nerve block initiation, analgesics required in the postanesthesia care unit (PACU), and sedation during surgery. Pain was evaluated using the Visual Analog Scale (VAS) in PACU. SPSS version 26 was used for statistical analysis, performing descriptive analysis, Student's t-tests, and Mann-Whitney U tests to compare non-parametric variables between the 2 groups. Statistically significant results had a P value of less than 0.05. Results: A total of 120 patients were randomly divided into 2 equal groups, each consisting of 50 males and 10 females. The mean age of intervention and case groups were 37.23 ± 13.30 and 38.43 ± 11.95 years, respectively. After performing statistical tests (Student's t-test and Mann-Whitney U test), there was no significant difference in the initiation time of nerve block, surgery initiation time, surgery duration, the amount of required sedation, VAS scores, and meperidine consumption (P > 0.05). None of the patients in both groups required conversion to GA. Conclusions: The primary goal was achieved in all included cases, and no patients required conversion to GA. The efficacy of ISB is the same whether or not it is combined with a SCPB. Interscalene block is an alternative RA approach for clavicle fractures. Thus, ISB alone is as efficient as when used in combination with SCPB.

6.
BMC Anesthesiol ; 24(1): 57, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38331721

ABSTRACT

BACKGROUND: The erector spinae plane block (ESPB) is a novel regional block technique for pain management following thoracic surgeries. However, there are minimal cases in which the technique was used as the main anesthesia technique during surgery. CASE PRESENTATION: Here, we report the successful use of ESBP for applying anesthesia in a case during an emergent thoracotomy for performing pericardiotomy and loculated tamponade evacuation. CONCLUSIONS: Using ESPB with a higher concentration of local anesthetics, in this case, prepared appropriate anesthesia for performing an emergent thoracotomy while avoiding multiple needle insertions and the risk of further hemodynamic instability.


Subject(s)
Nerve Block , Thoracotomy , Humans , Anesthesia, Conduction/methods , Anesthetics, Local , Nerve Block/methods , Thoracotomy/adverse effects
7.
Pain Res Manag ; 2024: 3720344, 2024.
Article in English | MEDLINE | ID: mdl-38223902

ABSTRACT

Background: Acetabular fracture surgeries are frequently accompanied by protracted and severe perioperative pain, and there is no consensus on optimal pain relief management. Aim: This study aimed at comparing the analgesic efficacy of fascia iliaca compartment block (FICB) and quadratus lumborum block (QLB) in patients with acetabular fractures undergoing surgery using the Stoppa method. Methods: In this double-blind, randomized, noninferiority clinical trial, adult patients undergoing spinal anesthesia for acetabular fracture surgery, in Imam Hossein Hospital, Tehran, Iran (IRCT20191114045435N1), were randomly divided into two groups: FICB (n = 22) and QLB (n = 24). The visual analog scale (VAS) was used to assess the pain intensity at different times for all participants. In addition, the dose of fentanyl required to induce the patient to sit for spinal anesthesia and the pain intensity were evaluated. Moreover, the duration of analgesia and the total amount of morphine consumed in the first 24 h following surgery were evaluated, analyzed, and compared between the two study groups. Results: FICB and QLB demonstrated effective comparative postoperative analgesic profiles following acetabular fracture surgery; however, no significant differences in VAS values were observed between the two groups during the study. FICB experienced reduced cumulative fentanyl consumption during spinal anesthetic placement, whereas QLB had a significantly lower total morphine demand in the initial postoperative 24 h period. Conclusion: The lateral QLB and FICB can be introduced as effective routes for analgesia in acetabular fracture surgery using the Stoppa method. Clinical Trial Registration. The study was prospectively registered in the clinical trials registry system, on 2021-02-17, with registration number: IRCT20191114045435N1.


Subject(s)
Hip Fractures , Pain, Postoperative , Adult , Humans , Analgesics, Opioid/therapeutic use , Fascia , Fentanyl , Hip Fractures/surgery , Iran , Morphine , Pain, Postoperative/drug therapy , Pain, Postoperative/etiology , Double-Blind Method
8.
Eur Spine J ; 33(3): 1081-1088, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38170270

ABSTRACT

PURPOSE: Spine surgeries have experienced exponential growth over the past 2 decades. These surgeries are often accompanied by long and severe perioperative pain, presenting a significant management challenge. This study aims to assess and compare the efficacy of two techniques for postoperative pain (POP) management in lumbar spine surgeries: ultrasound-guided erector spinae plane block (ESPB) and intraoperative freehand ESPB. METHODS: In this prospective randomized non-inferiority trial (Registration Number: IRCT20221107056427N1), adult patients who were candidates for lumbar spinal fusion surgery were randomly divided into two groups: ultrasound-guided ESPB (n = 29) and freehand ESPB (n = 29). The primary outcomes were the total amount of morphine consumed during the first 24 h following the surgery and the numerical rating scale (NRS) pain score at various time points within the first 24 h following the surgery. The secondary outcome was the fentanyl used during surgery. RESULTS: Participants in the intraoperative freehand approach had considerably higher total morphine consumption in the first postoperative 24 h. The trend of NRS changes in both the ultrasound-guided ESPB group and the freehand ESPB group during the first 24 h after surgery showed a significant decrease. Still, there was no significant difference between the two groups. However, the first analgesic demand time was significantly shorter in the intraoperative freehand ESPB group compared to the ultrasound-guided approach. CONCLUSION: According to our results, the ultrasound-guided approach of ESPB is more effective in POP management and opioid sparing in lumbar spinal fusion surgeries compared to the freehand approach. However, the data from this study are not sufficient to draw robust conclusions, and further randomized controlled trials with larger sample sizes are required to validate our results.


Subject(s)
Nerve Block , Spinal Fusion , Adult , Humans , Analgesics, Opioid/therapeutic use , Morphine , Pain, Postoperative/drug therapy , Pain, Postoperative/prevention & control , Prospective Studies , Ultrasonography, Interventional
9.
BMC Anesthesiol ; 23(1): 412, 2023 12 13.
Article in English | MEDLINE | ID: mdl-38093201

ABSTRACT

BACKGROUND: Postoperative nausea and vomiting (PONV) is a common side effect associated with general anesthesia. Both ondansetron and aprepitant been effectively used to prevent PONV. However, there is a disagreement of opinions regarding the superiority of these two drugs. This study aims to compare the efficacy of aprepitant with ondansetron in preventing PONV following orthognathic surgeries. METHODS: In this double-blinded clinical trial, 80 patients scheduled for orthognathic surgery at Imam Hossein Hospital, Tehran, Iran, were randomly assigned to two groups. A standardized anesthesia protocol was used for all patients. The first group received a placebo capsule administered one hour before the surgical procedure along with 4 mg (2 ml) of ondansetron intravenously after anesthesia induction. The second group was given 80 mg aprepitant capsules one hour before the surgery, followed by an injection of 2 ml intravenous distilled water after anesthesia induction. The occurrence and severity of PONV, the amount of rescue medication required, and the complete response of patients assessed within 24 h after the surgery. RESULTS: There were no significant differences in demographic data between the two groups. Patients in the aprepitant group had a significantly lower incidence and severity of nausea (2.5% versus 27.5%), vomiting (5% versus 25%), and required fewer rescue medications (7.5% versus 62.5%) compared to the ondansetron group. Additionally, the aprepitant group showed a higher complete response rate (90% versus 67.5%) in the 0-2 and 12-24 postoperative hours. CONCLUSION: According to the findings of this study, aprepitant has demonstrated a greater efficacy in preventing PONV following orthognathic surgery, when compared to ondansetron. TRIAL REGISTRATION: Iranian Registry of Clinical Trials (IRCT code: IRCT20211205053279N3), date of registration: 16/12/2022.


Subject(s)
Antiemetics , Orthognathic Surgery , Humans , Ondansetron/therapeutic use , Aprepitant , Postoperative Nausea and Vomiting/epidemiology , Postoperative Nausea and Vomiting/prevention & control , Postoperative Nausea and Vomiting/drug therapy , Antiemetics/therapeutic use , Iran , Double-Blind Method
10.
Arch Bone Jt Surg ; 11(8): 524-530, 2023.
Article in English | MEDLINE | ID: mdl-38736722

ABSTRACT

Objectives: Excessive blood loss is a critical complication of total hip arthroplasty. We intended to determine whether preoperative fibrinogen administration reduces perioperative bleeding and the need for blood transfusion in total hip arthroplasty surgery. Methods: In 4 months, 178 patients who underwent total hip arthroplasty were randomly assigned equally to intervention and placebo-control groups in a double-blinded, parallel two-arm randomized controlled trial. Both intravenously, 30 min before the start of the surgery, the intervention group received two grams of fibrinogen concentrate dissolved in 100 ml of distilled water. In contrast, the control group received 100 ml of normal saline solution. The amount of postoperative blood loss served as the main result, and the requirement for blood transfusions served as the secondary outcome. Results: In comparison to the placebo, administering fibrinogen concentrate considerably reduced the amount of blood loss (P=0.001) and the requirement for blood transfusions (P=0.004). Patients who got fibrinogen concentrate experienced no side effects. In addition, patients in the fibrinogen group had significantly lower hemoglobin and higher fibrinogen levels in the recovery room and received lesser blood transfusions (P<0.005) than the placebo group. Conclusion: In total hip arthroplasty, fibrinogen concentrate lessens postoperative bleeding and the requirement for blood transfusions.

11.
Langmuir ; 37(24): 7591-7599, 2021 06 22.
Article in English | MEDLINE | ID: mdl-34106713

ABSTRACT

The forward osmosis (FO) process suffers from unfavorable internal concentration polarization (ICP) of the solute within the support layer of thin-film composite forward osmosis (TFC-FO) membranes. To lower the ICP effect, a support layer with low tortuosity, high porosity, and interconnected pores is necessary. In the present investigation, sodium bicarbonate has been presented as a simple pore-forming agent to decline the ICP within a poly(ethersulfone) substrate. In particular, the porous poly(ethersulfone) support layer was fabricated by embedding sodium bicarbonate into the casting solution to form CO2 gas bubbles in the substrate during phase inversion in an acidic nonsolvent. Experimental results revealed that the separation performance of the TFC-FO membranes significantly improved. The most water-permeable membrane was prepared in the acidic nonsolvent (TFC-SB.3) and it demonstrated a water flux of 26.6 LMH and a reverse salt flux of 3.6 gMH in the FO test. In addition, the TFC-SB.3 membrane showed an 85% increase in water permeability (2.13 LMH/bar) with negligible change in salt rejection (94.3%). Such observations were based on the increase of substrate porosity and the improved connectivity of the finger-like channels through in situ CO2 gas bubbling that alleviate the ICP phenomena. Therefore, the current study presents a simple, scalable method to design a high-performance TFC-FO membrane.


Subject(s)
Sodium Bicarbonate , Water Purification , Membranes, Artificial , Osmosis , Permeability
12.
BMC Anesthesiol ; 20(1): 228, 2020 09 07.
Article in English | MEDLINE | ID: mdl-32894054

ABSTRACT

BACKGROUND: Bupivacaine, an amid-type local anesthetic, is widely used for clinical patients especially in pregnant women. In addition to neurotoxicity effect of bupivacaine, it can cross the placenta, accumulates in this tissue and retained in fetal tissues. Nevertheless, whether bupivacaine can cause neurotoxicity in fetus remains unclear. Hence, this study was design to investigate the effects of maternal bupivacaine use on fetus hippocampal cell apoptosis and the possible related mechanism. METHODS: On day 15 of pregnancy, sciatic nerve of pregnant wistar rat (180-200 g) were exposed by lateral incision of the right thigh and 0.2 ml of bupivacaine was injected. After their delivery, we randomly selected one male offspring of every mother. On day 30 after of their birth, the rat's hippocampi were isolated for molecular studies. Western blotting was used to examine the expression of cleaved caspase-3, caspase-8 and p-Akt in fetal hippocampus. RESULTS: Our results showed that maternal bupivacaine use caused a significant increment of cleaved caspase-3 and caspase-8 expression in fetal hippocampus compared with the sham group. In addition, maternally administered bupivacaine could significantly decrease hippocampal P.Akt/T.Akt ratio which was concurrent with an increment of cleaved caspase-3 and caspase-8 expression. CONCLUSION: Our data suggest that maternal bupivacaine use increases fetal hippocampal cell apoptosis markers such as caspase 8 and cleaved caspase 3, at least in part, via inhibiting the Akt activation.


Subject(s)
Anesthetics, Local/toxicity , Apoptosis/drug effects , Bupivacaine/toxicity , Hippocampus/drug effects , Prenatal Exposure Delayed Effects/chemically induced , Sciatic Nerve/drug effects , Anesthetics, Local/administration & dosage , Animals , Animals, Newborn , Apoptosis/physiology , Bupivacaine/administration & dosage , Caspase 3/biosynthesis , Caspase 8/biosynthesis , Female , Hippocampus/enzymology , Hippocampus/pathology , Male , Pregnancy , Prenatal Exposure Delayed Effects/enzymology , Prenatal Exposure Delayed Effects/pathology , Rats , Rats, Wistar , Sciatic Nerve/enzymology , Sciatic Nerve/pathology
13.
Int J Nanomedicine ; 15: 3983-3999, 2020.
Article in English | MEDLINE | ID: mdl-32606660

ABSTRACT

INTRODUCTION: In recent years, the use of cost-effective, multifunctional, environmentally friendly and simple prepared nanomaterials/nanoparticles have been emerged considerably. In this manner, different synthesizing methods were reported and optimized, but there is still lack of a comprehensive method with multifunctional properties. MATERIALS AND METHODS: In this study, we aim to synthesis the copper oxide nanoparticles using Achillea millefolium leaf extracts for the first time. Catalytic activity was investigated by in situ azide alkyne cycloaddition click and also A3 coupling reaction, and optimized in terms of temperature, solvent, and time of the reaction. Furthermore, the photocatalytic activity of the synthesized nanoparticles was screened in terms of degradation methylene blue dye. Biological activity of the synthesized nanoparticles was evaluated in terms of antibacterial and anti-fungal assessments against Staphylococcus aureus, M. tuberculosis, E. coli, K. pneumoniae, P. mirabili, C. diphtheriae and S. pyogenes bacteria's and G. albicans, A. flavus, M. canis and G. glabrata fungus. In the next step, the biosynthesized CuO-NPs were screened by MTT and NTU assays. RESULTS: Based on our knowledge, this is a comprehensive study on the catalytic and biological activity of copper oxide nanoparticles synthesizing from Achillea millefolium, which presents great and significant results (in both catalytic and biological activities) based on a simple and green procedure. CONCLUSION: Comprehensive biomedical and catalytic investigation of the biosynthesized CuO-NPs showed the mentioned method leads to synthesis of more eco-friendly nanoparticles. The in vitro studies showed promising and considerable results, and due to the great stability of these nanoparticles in a green media, effective biological activity considered as an advantageous.


Subject(s)
Biomedical Technology , Copper/pharmacology , Metal Nanoparticles/chemistry , Achillea/chemistry , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Bacteria/drug effects , Catalysis , Cell Survival/drug effects , Cycloaddition Reaction , Fungi/drug effects , Hep G2 Cells , Humans , Metal Nanoparticles/ultrastructure , Microbial Sensitivity Tests , Plant Extracts/chemistry , Solvents/chemistry , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Temperature , Time Factors , X-Ray Diffraction
14.
Mikrochim Acta ; 187(5): 298, 2020 04 28.
Article in English | MEDLINE | ID: mdl-32347371

ABSTRACT

A unique and novel µ-thin-layer chromatography method based on Sn(II) ion-imprinted polymer (Sn-IIP) for speciation of tin ion species in water and plasma samples is introduced for the first time. For this purpose, N-allylthiourea (NATU) and ethylene glycol dimethacrylate (EGDMA) were copolymerized in the presence of Sn(II). The obtained polymer particles were identified using multiple techniques like BET, FT-IR, XRD, and FESEM. The effects of different variables such as pH of the solution, mobile phase composition, and IIP per CaSO4 mass ratio on the separation efficiency were also evaluated. After completion of the separation process on the plate, its surface was scanned by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Under the established optimal condition, the detection limit, relative standard deviation (RSD) of responses, and linear dynamic range (LDR) of the method were obtained as 0.3 µg L-1, 3.5%, and 0.8-900 µg L-1 for Sn(II) and 0.4 µg L-1, 4%, and 1-740 µg L-1 for Sn(IV) assay, respectively. The developed method was finally applied to the speciation of tin in various water and plasma samples. Graphical abstract Schematic representation of µ-thin-layer chromatography method based on tin(II) ion-imprinted polymer (Sn-IIP) for speciation of tin ion species in water and plasma samples and scanned separated casts by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS).


Subject(s)
Lasers , Polymers/chemistry , Tin/analysis , Chromatography, Thin Layer , Humans , Mass Spectrometry , Molecular Structure , Particle Size , Surface Properties , Wastewater/chemistry
15.
Biotechnol Biofuels ; 13: 57, 2020.
Article in English | MEDLINE | ID: mdl-32206090

ABSTRACT

BACKGROUND: Microalgae, due to its well-recognized advantages have gained renewed interest as potentially good feedstock for biodiesel. Production of fatty acid methyl esters (FAMEs) as a type of biodiesel was carried out from Chlorella vulgaris bio-oil. Biodiesel was produced in the presence of nano-biocatalysts composed of immobilized lipase on functionalized superparamagnetic few-layer graphene oxide via a transesterification reaction. A hybrid of few-layer graphene oxide and Fe3O4 (MGO) was prepared and characterized. The MGO was functionalized with 3-aminopropyl triethoxysilane (MGO-AP) as well as with a couple of AP and glutaraldehyde (MGO-AP-GA). The Rhizopus oryzae lipase (ROL) was immobilized on MGO and MGO-AP using electrostatic interactions as well as on MGO-AP-GA using covalent bonding. The supports, MGO, MGO-AP, and MGO-AP-GA, as well as nano-biocatalyst, ROL/MGO, ROL/MGO-AP, and ROL/MGO-AP-GA, were characterized using FESEM, VSM, FTIR, and XRD. The few-layer graphene oxide was characterized using AFM and the surface charge of supports was evaluated with the zeta potential technique. The nano-biocatalysts assay was performed with an evaluation of kinetic parameters, loading capacity, relative activity, time-course thermal stability, and storage stability. Biodiesel production was carried out in the presence of nano-biocatalysts and their reusability was evaluated in 5 cycles of transesterification reaction. RESULTS: The AFM analysis confirmed the few-layer structure of graphene oxide and VSM also confirmed that all supports were superparamagnetic. The maximum loading of ROL (70.2%) was related to MGO-AP-GA. The highest biodiesel conversion of 71.19% achieved in the presence of ROL/MGO-AP-GA. Furthermore, this nano-biocatalyst could maintain 58.77% of its catalytic performance after 5 cycles of the transesterification reaction and was the best catalyst in the case of reusability. CONCLUSIONS: In this study, the synthesized nano-biocatalyst based on bare and functionalized magnetic graphene oxide was applied and optimized in the process of converting microalgae bio-oil to biodiesel for the first time and compared with bare lipase immobilized on magnetic nanoparticles. Results showed that the loading capacity, kinetic parameters, thermal stability, and storage stability improved by the functionalization of MGO. The biocatalysts, which were prepared via covalent bonding immobilization of enzyme generally, showed better characteristics.

16.
Carbohydr Polym ; 230: 115589, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31887865

ABSTRACT

This study was conducted to investigate the application of gamma irradiation as a means to control the release rate of catechin from polymer matrix. First, chitosan and polyvinyl alcohol (1:3) were mixed and later chitosan nanoparticles containing catechin were added to the mixture and coated on polylactic acid surface and then films were irradiated at 0, 40 and 60 kGy doses of gamma-ray. Irradiation lowered the water solubility value of the films, furthermore 60 kGy dose reduced the water vapor permeability and tensile strength without significant effect on elongation at break of films. Results of release test indicated that gamma-ray decreased release rate of catechin from polymer matrix and generally release in high-fat simulant was about 2.5 times slower than low-fat simulant. This study was undertaken to design a packaging material with controlled release ability of antioxidant compound over time for further application in oxidation-sensitive foods.

17.
Chemosphere ; 238: 124691, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31524626

ABSTRACT

In recent years, forward osmosis (FO) has represented numerous potential applications in safe water production. In this study, we improved the performance of FO thin film composite (TFC) membranes for the removal of trace organic compounds (TOrCs) by tuning the chemistry of its top active layer. The TFC membranes were synthesized by interfacial polymerization (IP) reaction between amine-containing monomers, e.g., meta-phenylene diamine (MPD) or para-phenylenediamine (PPD), and an acid chloride monomer, e.g., trimesoyl chloride (TMC). Owing to three free amine functionals over main core, melamine was used in the amine monomers solution to increase cross-linking among polyamide chains. Chemical and morphological characterization of the prepared membranes confirmed that melamine was successfully incorporated into the chemical structure of the top PA layer. Two agricultural toxic materials (atrazine and diazinon) were used to investigate the capability of the newly fabricated membranes in the removal of TOrCs. The obtained results showed that melamine-improved FO membranes provided higher atrazine and diazinon rejections in two different FO membrane configurations, including active layer facing feed solution (ALF) and active layer facing draw solution (ALD). The highest rejections of both diazinon (99.4%) and atrazine (97.3%) were achieved when the melamine modified MPD-based membrane served in ALF mode with 2 M NaCl as a draw solution.


Subject(s)
Humic Substances/analysis , Osmosis/physiology , Water Purification/instrumentation , Water Purification/methods , Atrazine/analysis , Diazinon/analysis , Membranes, Artificial , Nylons/chemistry , Phenylenediamines/chemistry , Polymerization , Sodium Chloride/chemistry , Triazines/chemistry , Tricarboxylic Acids/chemistry , Water/chemistry
18.
Environ Sci Pollut Res Int ; 26(2): 1181-1191, 2019 Jan.
Article in English | MEDLINE | ID: mdl-28871353

ABSTRACT

In recent years, forward osmosis (FO) has received considerable attention due to its huge potentials in water desalination. The thin film composite (TFC) membrane used in the FO desalination consists of a bottom support layer covered by an active layer on top. Polyamide (PA) is commonly employed as an active layer forming via interfacial polymerization between m-phenylenediamine (MPD) and trimesoyl chloride (TMC) monomers. In this study, the effects that the MPD and TMC concentrations could have on the performance and anti-fouling behavior of the obtained FO membrane have been investigated. Results showed that there is a trade-off relationship between the water flux and salt rejection, which by increasing MPD concentration, the water flux was reducedو while the salt rejection was enhanced. Also, by increasing the TMC concentration, an opposite trend was observed. Using 0.20 wt.% of TMC monomer, the highest water fluxes of 21.6 LMH and 29.3 LMH were achieved in two different membrane configurations. Furthermore, higher TMC concentration caused better anti-fouling property, when PA active layer of the membrane was in a high fouling potential environment.


Subject(s)
Membranes, Artificial , Osmosis , Waste Disposal, Fluid/methods , Nylons/chemistry , Permeability
19.
J Colloid Interface Sci ; 536: 328-338, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-30380432

ABSTRACT

Thin-film composite (TFC) membranes with high water flux and low reverse salt flux are the most conventional materials for forward osmosis (FO) process. However, these membranes are not suitable for natural or wastewaters treatment due to the intrinsic physicochemical and surface properties of the rejection layer. The present work shows the fabrication of new thin film nanocomposite (TFN) forward osmosis membranes incorporate superhydrophilic modified silica nanoparticles. Surface of silica nanoparticles were functionalized by quaternary ammonium groups and subsequently were coated using superhydrophilic wheel polyoxometalates (POM). TFN membranes containing different weight ratio of nanoparticles in PA rejection layer were synthesized by interfacial polymerization (IP) of m-phenylenediamine (MPD) and trimesoyl chloride (TMC) as monomers in aqueous and organic solution, respectively. POM coated silica nanoparticles were dispersed in aqueous solution of MPD monomer prior to IP process. The changing in the performance and physicochemical properties of TFN membranes incorporating with superhydrophilic nanoparticles were investigated by different instrumental analysis and were compared with a pristine TFC membrane. Compared to pristine TFC membrane, the TFN membrane with 0.2 wt% nanoparticle incorporation (TFNw0.2) showed superior water flux (18 vs. 31 LMH in FO mode) and negligible increases in reverse salt flux (6.25 vs. 8.45 gMH). In addition, better anti-fouling propensity toward protein (bovine serum albumin, BSA) and organic (sodium alginate, SA) foulant was observed. Therefore, Using newly developed thin film nanocomposite membranes may provide a novel class of high-performance membrane for FO processes.


Subject(s)
Biofouling/prevention & control , Nanocomposites/chemistry , Osmosis , Tungsten Compounds/chemistry , Water Purification , Water/chemistry , Hydrophobic and Hydrophilic Interactions , Particle Size , Permeability , Surface Properties
20.
IET Nanobiotechnol ; 12(6): 822-827, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30104457

ABSTRACT

This study concerns the optimisation of green synthesis of manganese oxide nanoparticles (MnO NPs) with Dittrichia graveolens (L.) extract via response surface methodology (RSM). Central composite design was used to evaluate the effect of pH, time, and the extract to the metal ratio on the synthesised nanoparticles (NPs). Nine runs were designed to investigate the effect of each parameter while NPs were synthesised under different conditions. Considering the p-values (p-value < 0.05), it is indicated that the extract to the metal ratio was the most effective parameter. The synthesised NPs were characterised using UV-vis. Synthesis of the NPs by polyphenolic compounds of green reducing agent and their stabilisation by curcumin was confirmed by Fourier transform infrared spectra and the surface morphology of the spherical MnO NPs was studied by field-emission scanning electron microscopy and transmission electron microscope techniques. The present researchers claimed the optimal condition as follows: time = 56.7 min, pH = 7.2, and the extract to the metal ratio = 87.9 v/v. MnO NPs at optimum condition were then employed for degradation of industrial dyes and they showed high dye degradation activity against Rhodamine B and light green dye. The average size of the synthesised MnO NPs at optimal condition was claimed to be nearly 38 nm.


Subject(s)
Green Chemistry Technology , Manganese Compounds/chemical synthesis , Metal Nanoparticles/chemistry , Oxides/chemical synthesis , Asteraceae/chemistry , Calibration , Curcumin/chemistry , Curcumin/pharmacology , Green Chemistry Technology/methods , Green Chemistry Technology/standards , Manganese Compounds/chemistry , Oxides/chemistry , Particle Size , Reducing Agents/chemistry , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Surface Properties/drug effects , X-Ray Diffraction
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