Effects of polysiloxanes with different molecular weights on in vitro cytotoxicity and properties of polyurethane/cotton–cellulose nanofiber nanocomposite films

2020 ◽  
Vol 11 (32) ◽  
pp. 5225-5237 ◽  
Author(s):  
Chang-An Xu ◽  
Bingfei Nan ◽  
Mangeng Lu ◽  
Zhencai Qu ◽  
Zhiyou Tan ◽  
...  
Keyword(s):  
Cellulose Nanofibers ◽  
In Vitro Cytotoxicity ◽  
Cotton Cellulose ◽  
Cellulose Nanofiber ◽  
Nanocomposite Films ◽  
Isophorone Diisocyanate ◽  
Molecular Weights ◽  
Polycarbonate Diol

A series of polyurethane/cotton–cellulose nanofiber nanocomposite films are manufactured using amino-terminated polydimethylsiloxane, polycarbonate diol, isophorone diisocyanate, and dispersed cotton–cellulose nanofibers.

scholarly journals Effects of Polyethylene Glycol Spacer Length and Ligand Density on Folate Receptor Targeting of Liposomal Doxorubicin In Vitro

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Kumi Kawano ◽  
Yoshie Maitani
Keyword(s):  
Polyethylene Glycol ◽  
Liposomal Doxorubicin ◽  
Folate Receptor ◽  
In Vitro Cytotoxicity ◽  
Receptor Targeting ◽  
Spacer Length ◽  
Ligand Density ◽  
Molecular Weights ◽  
Folate Receptor Targeting

The folate receptor is an attractive target for selective tumor delivery of liposomal doxorubicin (DXR) because it is abundantly expressed in a large percentage of tumors. This study examined the effect of polyethylene glycol (PEG) spacer length and folate ligand density on the targeting ability of folate-modified liposomes. Liposomes were modified with folate-derivatized PEG-distearoylphosphatidylethanolamine with PEG molecular weights of 2000, 3400, or 5000. The association of DXR-loaded liposomes with KB cells, which overexpress the folate receptor, was evaluated by flow cytometry at various ratios of folate modification. A low ratio of folate modification with a sufficiently long PEG chain showed the highest folate receptor-mediated association with the cells, but did not show the highest in vitro cytotoxicity. DXR release from folate-modified liposomes in endosomes might be different. These findings will be useful for designing folate receptor-targeting carriers.

Preparation, Characterization and In Vivo Biocompatibility Studies of Cotton Cellulose Nanofibers

2020 ◽  
Vol 20 (10) ◽  
pp. 6532-6541
Author(s):  
Ana C. C. Gouveia ◽  
Michele Munk ◽  
Virgínia Oliveira ◽  
Ana P. Ferreira ◽  
Humberto M. Brandão ◽  
...  
Keyword(s):  
Zeta Potential ◽  
Cellulose Nanofibers ◽  
Cotton Cellulose ◽  
Cellulose Nanofiber ◽  
X Ray Diffraction ◽  
Potential Health ◽  
X Ray ◽  
Transmission Electron ◽  
Shaped Particle

Cellulose nanofibers have mechanical properties that make them very attractive in a myriad of fields such as biomedicine, tissue engineering, biosensors, cosmetics and food packet products. To evaluate the potential health risks of airborne cellulose nanofibers, the cellulose nanofiber was prepared and characterized and then its pulmonary potential toxicity to a mouse model was studied. Cellulose nanofiber has been prepared by acid hydrolysis of cotton cellulose and characterized by transmission electron microscopy, zeta potential and X-ray diffraction analysis. Then, using a short-term inhalation test, the pulmonary biocompatibility of cotton cellulose nanofibers at different concentrations (0.5 mg/mL, 1 mg/mL and 2 mg/mL) were evaluated. Transmission electron images showed needle-shaped particle with a diameter of about 6–18 nm and a length of 85–225 μm. Zeta potential was −25.3±7.80 mV and the X-ray diffraction patterns indicate that cotton cellulose nanofiber has pure structural characteristics. The In Vivo results revealed that the exposure to cotton cellulose nanofiber did not alter the number of inflammatory cells or cytokine secretion by lung cells (p > 0.05). The results demonstrate that the cotton cellulose nanofiber is biocompatible and it is an environment-friendly nanomaterial with promise in various industrial sectors.

Preparation and Characterization of Cellulose Nanofiber/Zinc Oxide Composite Films

2020 ◽  
Vol 14 (2) ◽  
pp. 203-208 ◽  
Author(s):  
Xiuqiang Zhang ◽  
Suxia Ren ◽  
Xiaofeng He ◽  
Lili Dong ◽  
Wei Bai ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Zno Nanoparticles ◽  
Biomedical Applications ◽  
Cellulose Nanofibers ◽  
Composite Films ◽  
Cellulose Nanofiber ◽  
Nanocomposite Films ◽  
Zno Films ◽  
X Ray Diffraction

Zinc oxide (ZnO)/cellulose nanofiber (CNF) nanocomposite films were prepared using cellulose nanofibers and ZnO nanoparticles. First, suspensions of CNF and ZnO mixtures were blended with different CNF/ZnO ratios; then, the mixtures were stirred, homogenized, filtered, and hot pressed to form nanofilms with various ZnO weight ratios (0–50 wt%). Rheological tests showed that the CNF shear thinning behavior was not affected by the addition of ZnO. X-ray diffraction and scanning electron microscopy studies proved the existence of ZnO nanoparticles in the nanocomposite films. Thermogravimetric results indicated that the presence of ZnO had almost no effect on the thermal properties of the composite. As the ZnO content increased, the tensile strength and strain-to-failure rate decreased. In comparison with neat CNF nanofilms, the nanocomposite films showed greater antimicrobial ability against Gram-positive Staphylococcus aureus due to the presence of ZnO nanoparticles, allowing the CNF/ZnO films to be used in some targeted biomedical applications.

scholarly journals Banana starch nanocomposite with cellulose nanofibers isolated from banana peel by enzymatic treatment: In vitro cytotoxicity assessment

2019 ◽  
Vol 207 ◽  
pp. 169-179 ◽  
Author(s):  
H. Tibolla ◽  
F.M. Pelissari ◽  
J.T. Martins ◽  
E.M. Lanzoni ◽  
A.A. Vicente ◽  
...  
Keyword(s):  
Cellulose Nanofibers ◽  
In Vitro Cytotoxicity ◽  
Enzymatic Treatment ◽  
Banana Peel ◽  
Cytotoxicity Assessment

scholarly journals Effects of Two Different Cellulose Nanofiber Types on Properties of Poly(vinyl alcohol) Composite Films

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Kitti Yuwawech ◽  
Jatuphorn Wootthikanokkhan ◽  
Supachok Tanpichai
Keyword(s):  
Fiber Type ◽  
Cellulose Nanofibers ◽  
Composite Films ◽  
Cellulose Nanofiber ◽  
Ductile Deformation ◽  
Nanocomposite Films ◽  
Light Transmittance ◽  
Poly Vinyl Alcohol ◽  
Fiber Types ◽  
Sem Images

This work concerns a study on the effects of fiber types and content of cellulose nanofiber on mechanical, thermal, and optical properties polyvinyl alcohol (PVA) composites. Two different types of cellulose nanofibers, which are nanofibrillated cellulose (NFC) and bacterial cellulose (BC), were prepared under various mechanical treatment times and then incorporated into the PVA prior to the fabrication of composite films. It was found that tensile modulus of the PVA film increased with nanofibers content at the expense of its percentage elongation value. DSC thermograms indicate that percentage crystallinity of PVA increased after adding 2–4 wt% of the fibers. This contributed to the better mechanical properties of the composites. Tensile toughness values of the PVA/BC nanocomposite films were also superior to those of the PVA/NFC system containing the same fiber loading. SEM images of the composite films reveal that tensile fractured surface of PVA/BC experienced more ductile deformation than the PVA/NFC analogue. The above discrepancies were discussed in the light of differences between the two types of fibers in terms of diameter and their intrinsic properties. Lastly, percentage total visible light transmittance values of the PVA composite films were greater than 90%, regardless of the fiber type and content.

Soluble Thrombomodulin Purified from Human Urine Exhibits a Potent Anticoagulant Effect In Vitro and In Vivo

1995 ◽  
Vol 73 (05) ◽  
pp. 805-811 ◽  
Author(s):  
Yasuo Takahashi ◽  
Yoshitaka Hosaka ◽  
Hiromi Niina ◽  
Katsuaki Nagasawa ◽  
Masaaki Naotsuka ◽  
...  
Keyword(s):  
Human Urine ◽  
Specific Activity ◽  
Anticoagulant Activity ◽  
Rabbit Lung ◽  
Soluble Thrombomodulin ◽  
Molecular Weights ◽  
Dose Dependent Fashion ◽  
Dose Dependent

SummaryWe examined the anticoagulant activity of two major molecules of soluble thrombomodulin purified from human urine. The apparent molecular weights of these urinary thrombomodulins (UTMs) were 72,000 and 79,000, respectively. Both UTMs showed more potent cofactor activity for protein C activation [specific activity >5,000 thrombomodulin units (TMU)/mg] than human placental thrombomodulin (2,180 TMU/mg) and rabbit lung thrombomodulin (1,980 TMU/mg). The UTMs prolonged thrombin-induced fibrinogen clotting time (>1 TMU/ml), APTT (>5 TMU/ml), TT (>5 TMU/ml) and PT (>40 TMU/ml) in a dose-dependent fashion. These effects appeared in the concentration range of soluble thrombomodulins present in human plasma and urine. In the rat DIC model induced by thromboplastin, administration of UTMs by infusion (300-3,000 TMU/kg) restored the hematological abnormalities derived from DIC in a dose-dependent fashion. These results demonstrate that UTMs exhibit potent anticoagulant and antithrombotic activities, and could play a physiologically important role in microcirculation.

Toxicity of Heparinoids, with Special Reference to the Precipitation of Fibrinogen

1964 ◽  
Vol 12 (01) ◽  
pp. 232-261 ◽  
Author(s):  
S Sasaki ◽  
T Takemoto ◽  
S Oka
Keyword(s):  
Molecular Weight ◽  
Dextran Sulfate ◽  
Anticoagulant Activity ◽  
Molecular Structures ◽  
Severe Reaction ◽  
Clinical Use ◽  
Molecular Weights ◽  
Close Relationship

SummaryTo demonstrate whether the intravascular precipitation of fibrinogen is responsible for the toxicity of heparinoid, the relation between the toxicity of heparinoid in vivo and the precipitation of fibrinogen in vitro was investigated, using dextran sulfate of various molecular weights and various heparinoids.1. There are close relationships between the molecular weight of dextran sulfate, its toxicity, and the quantity of fibrinogen precipitated.2. The close relationship between the toxicity and the precipitation of fibrinogen found for dextran sulfate holds good for other heparinoids regardless of their molecular structures.3. Histological findings suggest strongly that the pathological changes produced with dextran sulfate are caused primarily by the intravascular precipitates with occlusion of the capillaries.From these facts, it is concluded that the precipitates of fibrinogen with heparinoid may be the cause or at least the major cause of the toxicity of heparinoid.4. The most suitable molecular weight of dextran sulfate for clinical use was found to be 5,300 ~ 6,700, from the maximum value of the product (LD50 · Anticoagulant activity). This product (LD50 · Anticoagulant activity) can be employed generally to assess the comparative merits of various heparinoids.5. Clinical use of the dextran sulfate prepared on this basis gave satisfactory results. No severe reaction was observed. However, two delayed reactions, alopecia and thrombocytopenia, were observed. These two reactions seem to come from the cause other than intravascular precipitation.

Platelet Microtubule Subunit Proteins

1979 ◽  
Vol 42 (05) ◽  
pp. 1630-1633 ◽  
Author(s):  
A G Castle ◽  
N Crawford
Keyword(s):  
Epithelial Cells ◽  
Gel Electrophoresis ◽  
Blood Platelets ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Lens Epithelial Cells ◽  
Molecular Weights ◽  
Kinetics Of ◽  
Microtubular Structures

SummaryBlood platelets contain microtubule proteins (tubulin and HMWs) which can be polymerised “in vitro” to form structures which resemble the microtubules seen in the intact platelet. Platelet tubulin is composed of two non-identical subunits a and p tubulin which have molecular weights around 55,000 but can be resolved in alkaline SDS-polyacrylamide gel electrophoresis. These subunits associate as dimers with sedimentation coefficients of about 5.7 S although it is not known whether the dimer protein is a homo- or hetero-dimer. The dimer tubulin binds the anti-mitotic drug colchicine and the kinetics of this binding are similar to those reported for neurotubulins. Platelet microtubules also contain two HMW proteins which appear to be essential and integral components of the fully assembled microtubule. These proteins have molecular weights greater than 200,000 daltons. Fluorescent labelled antibodies to platelet and brain tubulins stain long filamentous microtubular structures in bovine lens epithelial cells and this pattern of staining is prevented by exposing the cells to conditions known to cause depolymerisation of cell microtubules.

Formulation and Evaluation of Chitosan-Polyaniline Nanocomposites for Controlled Release of Anticancer Drug Doxorubicin

2018 ◽  
Vol 8 (2) ◽  
Author(s):  
Dillip Kumar Behera ◽  
Kampal Mishra ◽  
Padmolochan Nayak
Keyword(s):  
Tensile Strength ◽  
Drug Release ◽  
Nanocomposite Films ◽  
Casting Method ◽  
Sustained Drug Release ◽  
In Vitro Drug Release ◽  
Clay Particles ◽  
Solution Casting Method ◽  
Nanoclay Content

In this present work, chitosan (CS) crosslink with polyaniline (PANI) with montmorilonite (MMT) called as (CSPANI/MMT) and CS crosslink with PANI without MMT called as (CS-PANI) were prepared by employing the solution casting method. Further the formation of nanocomposites CS-PANI/MMT and CS-PANI were investigated using XRD, FTIR, SEM and tensile strength. Water uptake and swelling ratio of the CS-PANI and CS-PANI/MMT were found to decrease with increase in concentration of clay. Mechanical properties of the CS-PANI and CS-PANI/MMT were assessed in terms of tensile strength and extensibility using texture analyzer. Increase in tensile strength and reduction in extensibility was reported with increase in the nanoclay content. In vitro drug release study on CS-PANI and CS-PANI/MMT indicated pronounced sustained release of doxorubicin by the incorporation of clay particles in the CS polymer matrix. Overall CSPANI/MMT nanocomposite films exhibited improved mechanical and sustained drug release properties than CS-PANI.

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