Immobilization of Thrombin Inhibitors on Polyesters Surface: An Original Approach towards Materials Blood Compatibilization

2006 ◽  
Vol 514-516 ◽  
pp. 961-965 ◽  
Author(s):  
Claudio Salvagnini ◽  
Jacqueline Marchand-Brynaert
Keyword(s):  
Photoelectron Spectroscopy ◽  
Thrombin Inhibitors ◽  
Aromatic Azide ◽  
Poly Ethylene Terephthalate ◽  
Amide Derivatives ◽  
Human Thrombin ◽  
Coagulation Assay ◽  
Poly Ethylene ◽  
Derivatives Of

Piperazinyl-amide derivatives of N--(3-trifluoromethyl-benzenesulfonyl)-L-arginine were synthesized as graftable thrombin inhibitors. Their biological activity was evaluated in vitro, against human -thrombin, and in blood coagulation assay. The piperazinyl-amide derivatives were found to inhibit the activity of -thrombin in the micromolar range. The designed molecules were fixed on poly(ethylene terephthalate) (PET), and poly(butylene terephthalate) (PBT) by wet chemistry treatment (activation of hydroxyl chain-ends) and photochemistry (nitrene insertion by photoactivation of aromatic azide). The protocols were validated by X-ray photoelectron spectroscopy (XPS) and by radiochemical assay (liquid scintillation counting, LSC).

Surface Characterization and In Vitro Blood Compatibility of Poly(Ethylene Terephthalate) Immobilized with Hirudin

2005 ◽  
Vol 288-289 ◽  
pp. 421-424
Author(s):  
F. Li ◽  
Jin Wang ◽  
H. Sun ◽  
Nan Huang
Keyword(s):  
Free Energy ◽  
Photoelectron Spectroscopy ◽  
Surface Characterization ◽  
Ethylene Terephthalate ◽  
Blood Compatibility ◽  
Argon Plasma ◽  
Angle Measurement ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Poly(ethylene terephthalate) films were exposed under argon plasma glow discharge and induced polymerization of acrylic acid (AA) in order to introduce carboxylic acid group onto PET (PET-AA) assisting by ultroviolet radiation. Hirudin-immobilized PETs were prepared by the grafting of PET-AA, followed by chemical reaction with hirudin. The surface structure of the treated PET is determined by X-ray photoelectron spectroscopy (XPS). The wettability and surface free energy, interface free energy of the films is investigated by contact angle measurement. Platelet adhesion evaluatiion is conducted to examine the blood compatibility in vitro. Scanning electron microscopy (SEM) and optical microscopy reveal that the amounts of adhered, aggregated and morphologically changed platelets are reduced on hirudin-immobilized PET films.

Surface Characterization and Antibacterial Evaluation of Poly(Ethylene Terephthalate) Modified by Chitosan-Immobilization

2005 ◽  
Vol 288-289 ◽  
pp. 331-334 ◽  
Author(s):  
Peng Li ◽  
Jin Wang ◽  
W.C. Lu ◽  
H. Sun ◽  
Nan Huang
Keyword(s):  
Photoelectron Spectroscopy ◽  
Bacterial Adhesion ◽  
Surface Characterization ◽  
Ethylene Terephthalate ◽  
Attenuated Total Reflection ◽  
Poly Ethylene Terephthalate ◽  
Modified Surface ◽  
Poly Ethylene ◽  
Pet Films

Biomedical PET films were modified by the approach of chitosan-surface-grafting. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) revealed that chitosan molecules were successfully grafted on the PET surface. The bacterial adhesion on the modified surface was evaluated by bacteria plate counting in vitro and scanning electron microscopy (SEM). The results testified that chitosan did make the surface of PET become more antibacterial. The free energy of adhesion (∆Fadh) between the bacteria and the chitosan-immobilized surface of PET was calculated. The value of the ∆Fadh was positive, which suggests that the process of bacterial adhesion on the modified PET surface was not thermodynamically favorable, namely, not spontaneous.

Blood Compatibility of Chitosan Immobilized on Poly(Ethylene Terephthalate) Surface Modified by Plasma and Ultraviolet Grafting

2005 ◽  
Vol 288-289 ◽  
pp. 327-330 ◽  
Author(s):  
Jin Wang ◽  
P. Li ◽  
H. Sun ◽  
Ping Yang ◽  
Y.X. Leng ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Ethylene Terephthalate ◽  
Blood Compatibility ◽  
Attenuated Total Reflection ◽  
Grafting Modification ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Surface Modified ◽  
Pet Films

We report a study involving chitosan chains immobilized on poly (ethylene terephthalate) (PET) films by plasma and ultraviolet (UV) grafting modification. The surface structure of the modified PET is determined by means of attenuated total reflection Fourier transform infraed spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The results show that the chains of chitosan are successfully grafted on the surface of PET. Platelet adhesion evaluation in vitro is conducted to examine the blood compatibility in vitro. Scanning electron microscopy (SEM) and optical microscopy reveal that the amounts of adhered, aggregated and morphologically changed platelets are reduced on the chitosan-immobilized PET films. The number of platelet adhered on the modified film is reduced by almost 48% compared to the amount of platelets on the untreated film. Our result thus shows that chitosan immobilized on the PET surface improves blood compatibility.

ChemInform Abstract: THROMBIN INHIBITORS. 3. CARBOXYL-CONTAINING AMIDE DERIVATIVES OF Nα-SUBSTITUTED L-ARGININE

1981 ◽  
Vol 12 (16) ◽  
Author(s):  
R. KIKUMOTO ◽  
Y. TAMAO ◽  
K. OHKUBO ◽  
T. TEZUKA ◽  
S. TONOMURA ◽  
...  
Keyword(s):  
Thrombin Inhibitors ◽  
Amide Derivatives ◽  
Derivatives Of

Nimbolide from Azadirachta indica and its derivatives plus first-generation cephalosporin antibiotics: a novel drug combination for wound-infecting pathogens

RSC Advances ◽  
2015 ◽  
Vol 5 (109) ◽  
pp. 89503-89514 ◽  
Author(s):  
S. R. Dhanya ◽  
S. Nishanth Kumar ◽  
Vandana Sankar ◽  
K. G. Raghu ◽  
B. S. Dileep Kumar ◽  
...  
Keyword(s):  
Azadirachta Indica ◽  
Drug Combination ◽  
First Generation ◽  
Bacterial Pathogens ◽  
Generation Cephalosporin ◽  
Amide Derivatives ◽  
Cephalosporin Antibiotics ◽  
Novel Drug ◽  
Derivatives Of

We evaluate the in vitro efficacy of nimbolide, desacetylnimbin, and the amide derivatives of nimbolide in combination with first-generation cephalosporin antibiotics against major wound-associated bacterial pathogens.

scholarly journals Insights into Adsorption Characterization of Sulfated Xylans onto Poly(ethylene terephthalate)

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 825 ◽  
Author(s):  
Lidija Fras Zemljič ◽  
Nena Dimitrušev ◽  
Rok Zaplotnik ◽  
Simona Strnad
Keyword(s):  
Photoelectron Spectroscopy ◽  
Ethylene Terephthalate ◽  
Research Field ◽  
Polymer Composite Material ◽  
Coulomb Interactions ◽  
Poly Ethylene Terephthalate ◽  
Physical Interactions ◽  
Poly Ethylene ◽  
Repulsive Forces ◽  
Adsorption Desorption

The main aim of this investigation was to study the interaction of sulfated xylans as antithrombotic substances with poly(ethylene terephthalate) (PET) model films as a model for blood contacting surfaces. The adsorption of sulfated xylans onto PET model films was studied as a function of pH and ionic strength using the quartz crystal microbalance with dissipation (QCM-D) technique. The application of positively charged polyethyleneimine (PEI) as an anchoring polymer was done to improve the adsorption. The hydrophilic/hydrophobic properties of functionalized PET surfaces were monitored by goniometry, whilst their elemental composition was determined by X-ray photoelectron spectroscopy. Sulfated xylans adsorbed favorably at pH 5 by physical interactions and by entropy gain driven adsorption. Higher ionic strengths of solutions improved adsorption, due to the reduction of electrostatic repulsive forces between PET surfaces and anionic xylans’ macromolecules. The intermediate PEI layer caused more extensive and stable adsorption due to Coulomb interactions. The surface modifications presented in this work provided important information regarding the adsorption/desorption phenomena between antithrombotic sulfated xylans and PET surfaces. The latter is of great interest when preparing advanced polymer composite material such as functional antithrombotic PET surfaces for blood-contacting medical devices and presents an extremely challenging research field.

Thrombin inhibitors. 3. Carboxyl-containing amide derivatives of N.alpha.-substituted L-arginine

1980 ◽  
Vol 23 (12) ◽  
pp. 1293-1299 ◽  
Author(s):  
Ryoji Kikumoto ◽  
Yoshikuni Tamao ◽  
Kazuo Ohkubo ◽  
Tohru Tezuka ◽  
Shinji Tonomura ◽  
...  
Keyword(s):  
Thrombin Inhibitors ◽  
Amide Derivatives ◽  
Derivatives Of
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