Preparation and Evaluation of Poly(γ-glutamic acid)-Based Anti-Adhesion Membranes

2007 ◽  
Vol 342-343 ◽  
pp. 225-228 ◽  
Author(s):  
Young Gwang Ko ◽  
Kwan Han Yoon ◽  
Chung Park ◽  
Moon Hee Sung ◽  
Oh Kyoung Kwon ◽  
...  
Keyword(s):  
Glutamic Acid ◽  
Animal Study ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Sprague Dawley ◽  
Electrospinning Technique ◽  
Water Contact ◽  
Tissue Adhesion ◽  
Preparation And Evaluation

Poly(γ-glutamic acid)(γ-PGA) based nanofiber sheets were prepared by using electrospinning technique to evaluate the ability of the prevention of postoperative tissue adhesion. The anti-adhesion membranes were prepared from poly(γ-glutamic acid) and PLGA with different compositions by electrospinning. Also nonsteroidal anti-inflammatory drug (ibuprofen) was incorporated during fabrication of nanofibers. Various electrospun nanofibers were characterized by the measurements of microstructure (surface morphology and fiber diameter by SEM), ATR-FTIR, water contact angle and in vivo animal study using Sprague Dawley rat model. The average diameter of nanofibers electrospun from trifluoroacetic acid (TFA) solution ranged from 300 nm to 900 nm, approximately. From in vivo animal study, it was observed that ibuprofen-incorporated γ- PGA nanofiber sheet was significantly effective in preventing tissue adhesion and inducing wound healing, probably due to the appropriate hydrophilicity of γ-PGA preventing shrinkage of the sheet and appropriate barrier property, while PLGA nanofibrous mat was dramatically contracted in in vivo due to its high hydrophobicity resulted in insufficient coverage of wound.

scholarly journals How does intraarticular dexmedetomidine injection effect articular cartilage and synovium? An animal study

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Başak Akça ◽  
Aysun Ankay Yılbaş ◽  
Filiz Üzümcügil ◽  
Berkem Büyükakkuş ◽  
Elham Bahador Zırh ◽  
...  
Keyword(s):  
Pain Relief ◽  
Knee Joint ◽  
Animal Study ◽  
Left Knee ◽  
Control Group ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Arthroscopic Knee ◽  
The Right

Abstract Background Intraarticular injections are widely used to provide pain relief after arthroscopic procedures and minimize the use of opioids. Dexmedetomidine has been proven to potentiate pain relief and postpone the demand for the first analgesic drug when it is used intraarticularly following arthroscopic knee procedures. However, the effects of dexmedetomidine on articular structures have not yet been evaluated. Our aim was to determine the effects of intraarticular dexmedetomidine injection on articular structures such as cartilage and synovium. Design Animal study. Methods Twenty adult rats (Sprague-Dawley) were enrolled in the study. Following appropriate aseptic and anesthetic conditions, dexmedetomidine (100 mcg/ml) (0.25 ml) was injected into the right knee joint (the study group) and normal saline solution (0.25 ml) into the left knee joint (the control group) of the rats. Four rats were sacrificed from each group on days 1, 2, 7, 14, and 21, and knee joint samples were obtained. Histologists evaluated the articular and periarticular regions and the synovium using histological sections, and a five-point scale was used to grade the inflammatory changes in a blinded manner. Results The groups were found to be similar in terms of median congestion scores, edema and inflammation scores, subintimal fibrosis, neutrophil activation and cartilage structure at each of the time intervals. Conclusion In our placebo-controlled, in vivo trial, the intraarticular use of dexmedetomidine seemed to be safe with respect to the studied histopathological parameters. However, complementary studies investigating the histopathological effects, analgesic dosage and adverse effects of dexmedetomidine on damaged articular structure models are needed.

scholarly journals Synthesis and Characterization of Stable and Binder-Free Electrodes of TiO2Nanofibers for Li-Ion Batteries

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Phontip Tammawat ◽  
Nonglak Meethong
Keyword(s):  
Electron Microscopy ◽  
Electrochemical Impedance ◽  
Coulombic Efficiency ◽  
Electronic Conductivity ◽  
Lithium Ion ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Reversible Capacity ◽  
Electrospinning Technique ◽  
Binder Free

An electrospinning technique was used to fabricate TiO2nanofibers for use as binder-free electrodes for lithium-ion batteries. The as-electrospun nanofibers were calcined at 400–1,000°C and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). SEM and TEM images showed that the fibers have an average diameter of ~100 nm and are composed of nanocrystallites and grains, which grow in size as the calcination temperature increases. The electrochemical properties of the nanofibers were evaluated using galvanostatic cycling and electrochemical impedance spectroscopy. The TiO2nanofibers calcined at 400°C showed higher electronic conductivity, higher discharge capacity, and better cycling performance than the nanofibers calcined at 600, 800, and 1,000°C. The TiO2nanofibers calcined at 400°C delivered an initial reversible capacity of 325 mAh·g−1approaching their theoretical value at 0.1 C rate and over 175 mAh·g−1at 0.3 C rate with limited capacity fading and Coulombic efficiency between 96 and 100%.

Fabrication of a Novel Electrospun Polyacrylonitrile/Giant Ball {Mo132} Composite Nanofibrous Mats in Adsorption of 2-CEES

2019 ◽  
Vol 3 (2) ◽  
pp. 130-138
Author(s):  
Reza Haddad ◽  
Mehdi Dusti Telgerd ◽  
Hojjatalla Hadi ◽  
Mohammad Sadeghinia
Keyword(s):  
Room Temperature ◽  
Composite Nanofibers ◽  
Sulfur Mustard ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Heterogeneous Structure ◽  
Adsorption Ability ◽  
Sem Images ◽  
Electrospinning Technique ◽  
Good Ability

Background: Polyacrylonitrile/Mo132 composite nanofibers mats was synthesized by an electrospinning technique using PAN and giant ball nano-polyoxomolybdateMo132. The nanocluster Mo132 was mixed with PAN solution and then electrospun to produce bead-free nanofibers. The aim of this study is to evaluate the adsorption ability of electrospun composite nanofibers against sulfur mustard stimulants and assess the possibility of using the electrospun nanofibers as protective membranes in chemical masks and warfare clothing. Adsorption of sulfur mustard stimulants was investigated on the surface of PAN nanofibers embedded with keplerate nano-polyoxomolybdate. Methods: In order to study the 2-CEES adsorption ability, the prepared PAN/Mo132 nanofibers composite was further prepared and exposed to 2-CEES solution. The surface morphology and other properties of the PAN/Mo132 nanofibers composite were characterized by various techniques, including SEM, TEM, FT-IR, UV-Vis. SEM images which showed that the average diameter of the fibers was found to be between 100-120 nm. Results: The adsorption efficiency of PAN/Mo132 composite in adsorption of 2-CEES was obtained 89% after 7h at room temperature. The results showed that composite nanofibers PAN/Mo132 will have a good ability as protective clothing and chemical masks against chemical warfare agents. Conclusion: PAN/Mo132 nanofibers were prepared by electrospinning method. The leaching of Mo132 from the nanofibers was not observed, meaning that the catalyst had excellent stability and could be used as a heterogeneous structure against the adsorption of sulfur mustard stimulant at room temperature. This composite nanofibers membrane exhibited good performance to adsorb 2-CEES in comparison with pure PAN. The adsorption rate of 2-CEES increases with increasing the amount of Mo132 embedded in the PAN nanofibers.

scholarly journals Fabrication and Evaluation of Polycaprolactone/Gelatin-Based Electrospun Nanofibers with Antibacterial Properties

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Lor Huai Chong ◽  
Mim Mim Lim ◽  
Naznin Sultana
Keyword(s):  
Drug Loading ◽  
Antibacterial Properties ◽  
Electrospun Nanofibers ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Electrospinning Technique ◽  
Water Contact ◽  
Nanofibrous Scaffolds ◽  
Model Drug

Nanofibrous scaffolds were fabricated through blending of a synthetic polymer, polycaprolactone (PCL), and a natural polymer, gelatin (GE), using an electrospinning technique. Processing and solution parameters were optimized to determine the suitable properties of PCL/GE-based nanofibers. Several characterizations were conducted to determine surface morphology by scanning electron microscopy (SEM), wettability using water contact angle measurement, and chemical bonding analysis using attenuated total reflectance (ATR) of PCL/GE-based nanofibers. Experimental results showed that 14% (w/v) PCL/GE with a flow rate of 0.5 mL/h and 18 kV demonstrated suitable properties. This nanofiber was then further investigated for itsin vitrodegradation, drug loading (using a model drug, tetracycline hydrochloride), and antibacterial testing (using zone inhibition method).

Morphology and Mechanical Properties of the Polyurethane/PANI-DBSA Blend Nanofibers by the Electrospinning Technique

2013 ◽  
Vol 651 ◽  
pp. 87-90 ◽  
Author(s):  
Xiu Lian Wang ◽  
Liu Xue Zhang
Keyword(s):  
Sulfonic Acid ◽  
Composite Nanofibers ◽  
Weight Ratio ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Electrospinning Process ◽  
Sem Images ◽  
Electrospinning Technique ◽  
Dodecylbenzene Sulfonic Acid ◽  
Morphology And Mechanical Properties

In this study, composite nanofibers of polyaniline doped with dodecylbenzene sulfonic acid (PANI-DBSA) and polyurethane (PU) were prepared via an electrospinning process. The morphology, diameter, and structure of the electrospun nanofibers were investigated. SEM images showed that the morphology and diameter of the nanofibers were mainly affected by the weight ratio of the blend. The average diameter of the nanofibers was 370–1620 nm. The diameter gradually decreased with increasing PANI-DBSA content in the blend, and more beads were obtained in the composite.

Effect of LiCl and non-ionic surfactant on morphology of polystyrene electrospun nanofibers

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Delaram Fallahi ◽  
Mehdi Rafizadeh ◽  
Naser Mohammadi ◽  
Behrooz Vahidi
Keyword(s):  
Electron Microscopy ◽  
Surface Tension ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Ionic Surfactant ◽  
Electrospun Fibers ◽  
Electrospinning Technique ◽  
Solution Surface ◽  
Solution Conductivity ◽  
Scanning Electron

AbstractPolystyrene fibers were produced by the electrospinning technique. The effects of solution conductivity, surface tension and concentration on morphology and average diameter of electrospun fibers were investigated by scanning electron microscopy (SEM). Solutions of 12, 10, 8, 6% (w/v) polystyrene in dimethylformamide were prepared. Lithium Chloride and a non-ionic surfactant were used to change the conductivity and surface tension of the solutions, respectively. The results indicate that increasing the solution conductivity eliminates the bead formation and increases the fiber diameters. By addition of salt, fine and consistent fibers could be produced from electrospinning of 8% (w/v) PS/DMF solution. Adding 0.1% surfactant reduces the solution surface tension and results in smaller beads and higher fiber diameters. By increasing the amount of surfactant to 0.3%, big beads and thinner fibers are produced.

Preparation and Characterization of Sandwich Structure Purification Material via Gas-Jet/Electrospinning Technique

2012 ◽  
Vol 531 ◽  
pp. 14-18
Author(s):  
Tai Qi Liu ◽  
Bin Bin Cao ◽  
Xiao Long Zhao ◽  
Chen Wang ◽  
Ruo Fan Zhang ◽  
...  
Keyword(s):  
Sandwich Structure ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Antibacterial Activities ◽  
Nano Particles ◽  
Gas Jet ◽  
Nano Tio2 ◽  
Electrospinning Technique ◽  
High Efficient

Nano-TiO2 is a high efficient and no poisonous light induced catalyst. It is important how to immobilize it on some supporter for its application. In this paper, The Nylon-6 (PA-6) nanofibres bearing TiO2 nano-particles were prepared via gas-jet/electrospinning technique. The resulted materials were characterized by XRD, SEM, TEM, EDX and TG techniques, and antibacterial activities of the resulted fibers were tested by Shake Flask method. The results show that fibers bearing nano-TiO2, in an average diameter from 60 to 65nm were prepared, and the antibacterial efficiency of these gas-jet/electrospun nanofibers can reach 99.74%. The titled fibers can be loaded in a sandwich structure nanofiber super-cleaning material by hot-press process, and its filtration efficiency can reach 99.50% with 1µm polystyrene microspheres as the filter media.

Enhancing the Superhydrophobic Behavior of Electrospun Fibers via Graphene Addition and Heat Treatment

2010 ◽  
Author(s):  
M. Ceylan ◽  
R. Asmatulu
Keyword(s):  
Heat Treatment ◽  
Contact Angle ◽  
Water Contact Angle ◽  
Fiber Surface ◽  
Electrospun Nanofibers ◽  
Contact Angles ◽  
Polymeric Fibers ◽  
Electrospinning Technique ◽  
Water Contact ◽  
Nanocomposite Fibers

Polyvinyl chloride (PVC) fibers incorporated with graphene nanoflakes were produced using electrospinning technique, and then superhydrohobicity of the electrospun nanofibers were investigated as a function of inclusion and temperature. In the absence of graphene, water contact angle of the fibers is below 140°; however, the water contact angle values of 0.5, 1, 2 and 4% graphene in fibers become 142, 152, 165 and 166°, respectively. Using a heat treatment, the contact angle values of samples also increase up to glass transition temperature of PVC. This indicates that graphene inclusions in the polymeric fibers and temperature drastically change the surface morphology and chemistry, which results in higher contact angles. The reason behind this phenomena may be the formation of smaller nanosized graphene bumps on the fiber surface that make the contact area between the droplet and the fiber extremely small. As a result, this process minimizes attractive forces between the water molecules and surface atoms of the rough nanocomposite fibers to bead up and rolls off.

Preparation of Poly(vinyl alcohol)/Polyoxalate Composite Nanofibers by Electrospinning and Drug Release Profiles

2014 ◽  
Vol 894 ◽  
pp. 369-373
Author(s):  
Nutthakritta Phromviyo ◽  
Ekaphan Swatsitang ◽  
Apiwat Chompoosor
Keyword(s):  
Drug Release ◽  
Rhodamine B ◽  
Vinyl Alcohol ◽  
In Vitro Release ◽  
Control Release ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Poly Vinyl Alcohol ◽  
Electrospinning Technique

This study investigated the use of a biodegradable polyoxalate blended with poly (vinyl alcohol) nanofibers to tailor properties of nanofibers and to control release of Rhodamine B from nanofibers. Nanofibers were prepared using an electrospinning technique. The morphology and average diameter of electrospun nanofibers were investigated using scanning electron microscopy. It was found that poly (vinyl alcohol) to polyoxalate ratio had a significant effect on the size of nanofibers (~175-403 nm). An in vitro release study showed that rate of Rhodamine B release increased with increasing poly (vinyl alcohol)/polyoxalate ratios yielding rate of release in the range of 0.1980.469 mg%/min. The mechanism of rhodamine B release can be explained by a two-stage process of diffusion and degradation. The results suggested that a water-insoluble polyoxalate could govern the rate of drug release. The ability to tune the release of chemicals from nanofibers has significant implications for controlled release of drugs.

Sinusoidal Cells in Bone Marrow Take Up BSA-Au Conjugates in the Presence of an Artificial Blood Substitute

1985 ◽  
Vol 43 ◽  
pp. 700-701
Author(s):  
J.S. Geoffroy ◽  
R.P. Becker
Keyword(s):  
Bone Marrow ◽  
Los Angeles ◽  
Iliac Artery ◽  
Blood Substitute ◽  
Sprague Dawley ◽  
Coated Pits ◽  
Sinusoidal Cells ◽  
Artificial Blood ◽  
Left Common Iliac Artery

The pattern of BSA-Au uptake in vivo by endothelial cells of the venous sinuses (sinusoidal cells) of rat bone marrow has been described previously. BSA-Au conjugates are taken up exclusively in coated pits and vesicles, enter and pass through an “endosomal” compartment comprised of smooth-membraned tubules and vacuoles and cup-like bodies, and subsequently reside in multivesicular and dense bodies. The process is very rapid, with BSA-Au reaching secondary lysosmes one minute after presentation. (Figure 1)In further investigations of this process an isolated limb perfusion method using an artificial blood substitute, Oxypherol-ET (O-ET; Alpha Therapeutics, Los Angeles, CA) was developed. Under nembutal anesthesia, male Sprague-Dawley rats were laparotomized. The left common iliac artery and vein were ligated and the right iliac artery was cannulated via the aorta with a small vein catheter. Pump tubing, preprimed with oxygenated 0-ET at 37°C, was connected to the cannula.

Sign in / Sign up

Export Citation Format

Share Document