Bacterial Enzyme Responsive Polymersomes: A Closer Look at the Degradation Mechanism of PEG-block-PLA Vesicles

2014 ◽  
Vol 67 (4) ◽  
pp. 578 ◽  
Author(s):  
Katrin-Stephanie Tücking ◽  
Stephan Handschuh-Wang ◽  
Holger Schönherr
Keyword(s):  
Lactic Acid ◽  
Pathogenic Bacteria ◽  
Degradation Mechanism ◽  
Wound Dressings ◽  
Proteinase K ◽  
Poly Lactic Acid ◽  
Fluorescence Lifetime Imaging ◽  
Stimuli Responsive ◽  
Bacterial Enzyme ◽  
Poly Ethylene

Stimuli-responsive polymersomes that are selectively cleaved by enzymes of pathogenic bacteria are herein reported. The local disruption of the polyester wall in poly(ethylene glycol)-block-poly(lactic acid) (PEG-b-PLA) polymersomes filled with reporter dyes owing to enzymatic degradation by proteinase K was monitored by fluorescence lifetime imaging microscopy. Capsule opening occurred on timescales of minutes to hours, leading to the release of the dye, followed by a slow capsule disintegration, and finally cleavage into monomeric lactic acid over several weeks. These nanocontainers represent a promising element in novel theranostic systems for potential application in advanced wound dressings.

Thermal degradation kinetics of Opuntia Ficus Indica flour and talc-filled poly (lactic acid) hybrid biocomposites by TGA analysis

2021 ◽  
pp. 002199832110082
Author(s):  
Azzeddine Gharsallah ◽  
Abdelheq Layachi ◽  
Ali Louaer ◽  
Hamid Satha
Keyword(s):  
Thermal Stability ◽  
Lactic Acid ◽  
Thermal Degradation ◽  
Degradation Kinetics ◽  
Degradation Mechanism ◽  
Melt Processing ◽  
Thermal Degradation Kinetics ◽  
Poly Lactic Acid ◽  
Opuntia Ficus Indica ◽  
Model Free

This paper reports the effect of lignocellulosic flour and talc powder on the thermal degradation behavior of poly (lactic acid) (PLA) by thermogravimetric analysis (TGA). Lignocellulosic flour was obtained by grinding Opuntia Ficus Indica cladodes. PLA/talc/ Opuntia Ficus Indica flour (OFI-F) biocomposites were prepared by melt processing and characterized using Wide-angle X-ray scattering (WAXS) and Scanning Electron Microscope (SEM). The thermal degradation of neat PLA and its biocomposites can be identified quantitatively by solid-state kinetics models. Thermal degradation results on biocomposites compared to neat PLA show that talc particles at 10 wt % into the PLA matrix have a minor impact on the thermal stability of biocomposites. Loading OFI-F and Talc/OFI-F mixture into the PLA matrix results in a decrease in the maximum degradation temperature, which means that the biocomposites have lower thermal stability. The activation energies (Ea) calculated by the Flynn Wall Ozawa (FWO) and Kissinger Akahira Sunose (KAS) model-free approaches and by model-fitting (Kissinger method and Coats-Redfern method) are in good agreement with one another. In addition, in this work, the degradation mechanism of biocomposites is proposed using Coats-Redfern and Criado methods.

The effect of poly(ethylene glycol) as plasticizer in blends of poly(lactic acid) and poly(butylene succinate)

2015 ◽  
Vol 133 (8) ◽  
pp. n/a-n/a ◽  
Author(s):  
Weraporn Pivsa-Art ◽  
Kazunori Fujii ◽  
Keiichiro Nomura ◽  
Yuji Aso ◽  
Hitomi Ohara ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Ethylene Glycol ◽  
Poly Lactic Acid ◽  
Poly Ethylene Glycol ◽  
Butylene Succinate ◽  
Poly Ethylene

Immobilization of trypsin onto poly(ethylene terephthalate)/poly(lactic acid) nonwoven nanofiber mats

2015 ◽  
Vol 104 ◽  
pp. 48-56 ◽  
Author(s):  
Teresa R. Silva ◽  
Daniela P. Rodrigues ◽  
Jorge M.S. Rocha ◽  
M. Helena Gil ◽  
Susana C.S. Pinto ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Ethylene Terephthalate ◽  
Poly Lactic Acid ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Nanofiber Mats

Biodegradable Microfluidic Device: Hydrolysis, Decomposition and Surface Modification

2010 ◽  
Vol 447-448 ◽  
pp. 755-759 ◽  
Author(s):  
Jia En Low ◽  
Wei Xiang Koh ◽  
Joon Kit Lai ◽  
Yan Jie Lee ◽  
Xu Li ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Microfluidic Device ◽  
Ph Value ◽  
Blood Compatibility ◽  
Blood Clot ◽  
Hydrophobic Surface ◽  
Poly Lactic Acid ◽  
Water Contact ◽  
Chemical Grafting ◽  
Poly Ethylene

Poly(lactic acid) (PLA) is a biodegradable and biocompatible aliphatic polyester whose lactic acid monomers are derived from renewable resources such as corn and sugar beet. As a thermal plastic it can be processed through compounding and injection. As such, we have developed a microfludic device using PLA aimed at blood dialysis application. To quantify the degradation of PLA, its hydrolysis at different pH value was studied. To study the bioresorbable property of these fabricated devices, its decomposition was tested by morphology observation and weight change measurements after embedding in soil under simulated environmental conditions. Upon contact with a hydrophobic surface, platelets and prothrombin are always activated to attach to the surface, resulting in blood clot. This would block the blood flow through the dialysis channels in the microfluidic device. To improve the hydrophilicity, hence the blood compatibility, chemical grafting of a hydrophilic polymer, poly(ethylene oxide) methacrylate (PEGmA), onto the surface of PLA microfluidic device was carried out and the changes in hydrophilicity was monitored through measuring the water contact angle. Our results indicate that chemical grafting of PEGmA significantly improves the hydrophilicity of the device surface.

Rheology of complex biobased quaternary blends: Poly(lactic acid) [poly(ethylene oxide)]/poly(ether-b-amide)/poly(amide 11)

2021 ◽  
Vol 65 (3) ◽  
pp. 437-451
Author(s):  
Leire Sangroniz ◽  
Teodora Gancheva ◽  
Basil D. Favis ◽  
Alejandro J. Müller ◽  
Antxon Santamaria
Keyword(s):  
Lactic Acid ◽  
Ethylene Oxide ◽  
Poly Lactic Acid ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Compatibility and physical properties of poly(lactic acid)/poly(ethylene terephthalate glycol) blends

2012 ◽  
Vol 20 (12) ◽  
pp. 1300-1306 ◽  
Author(s):  
Jun Yong Park ◽  
Sung Yeon Hwang ◽  
Won Jae Yoon ◽  
Eui Sang Yoo ◽  
Seung Soon Im
Keyword(s):  
Lactic Acid ◽  
Physical Properties ◽  
Ethylene Terephthalate ◽  
Poly Lactic Acid ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Poly(lactic acid)−Poly(ethylene oxide) (PLA−PEG) Nanoparticles:  NMR Studies of the Central Solidlike PLA Core and the Liquid PEG Corona

Langmuir ◽  
2002 ◽  
Vol 18 (9) ◽  
pp. 3669-3675 ◽  
Author(s):  
C. R. Heald ◽  
S. Stolnik ◽  
K. S. Kujawinski ◽  
C. De Matteis ◽  
M. C. Garnett ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Ethylene Oxide ◽  
Poly Lactic Acid ◽  
Nmr Studies ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene
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