scholarly journals Heparinization of bovine pericardial scaffold by layer-by-layer (LBL) assembly technique

Author(s):  
My Thi Ngoc Nguyen ◽  
Ha Le Bao Tran
2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Qiangying Yi ◽  
Gleb B. Sukhorokov ◽  
Jin Ma ◽  
Xiaobo Yang ◽  
Zhongwei Gu

Phase change materials absorb the thermal energy when changing their phases (e.g., solid-to-liquid) at constant temperatures to achieve the latent heat storage. The major drawbacks such as limited thermal conductivity and leakage prevent the PCMs from wide application in desired areas. In this work, an environmentally friendly and low cost approach, layer-by-layer (LbL) assembly technique, was applied to build up ultrathin shells to encapsulate the PCMs and therefore to regulate their changes in volume when the phase change occurs. Generally, the oppositely charged strong polyelectrolytes Poly(diallyldimethylammonium chloride) (PDADMAC) and Poly(4-styrenesulfonic acid) sodium salt (PSS) were employed to fabricate multilayer shells on emulsified octadecane droplets using either bovine serum albumin (BSA) or sodium dodecyl sulfate (SDS) as surfactant. Specifically, using BSA as the surfactant, polyelectrolyte encapsulated octadecane spheres in size of ∼500 nm were obtained, with good shell integrity, high octadecane content (91.3% by mass), and good thermal stability after cycles of thermal treatments.


RSC Advances ◽  
2015 ◽  
Vol 5 (72) ◽  
pp. 58499-58503 ◽  
Author(s):  
Shiwei Wang ◽  
Zhuo Chen ◽  
Ahmad Umar ◽  
Yao Wang ◽  
Peng-gang Yin

Single component was used to construct conjugated polymer multilayer films by electric-field induced layer-by-layer assembly technique, which provides a universal approach for CPs and broadens the applicable scope of LBL assembly technique.


RSC Advances ◽  
2016 ◽  
Vol 6 (24) ◽  
pp. 20286-20293 ◽  
Author(s):  
Farzana Khan ◽  
Panpan Liu ◽  
Fujun Xu ◽  
Ying Ma ◽  
Yiping Qiu

This work utilizes layer-by-layer (LbL) assembly technique to dye cotton fabrics and investigates the dye aggregation in these polymer matrixes.


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Sepehr Lajevardi Esfahani ◽  
Shohre Rouhani ◽  
Zahra Ranjbar

Abstract It proved that the most destructive effects of the toxic Al3+ ion on the human nervous system and disease that are involved with this system, such as Alzheimer's. The development of solid-state electrodes is still in its infancy during the sensor-based detection methods for Al3+. Hence, in this study, a novel flexible ITO/PET-based electrochemical solid-state sensor was designed and constructed. Modification of the surface of electrode bedding was done by layer-by-layer (LbL) assembly of Mg–Al LDH. nanoplatelets along with alizarin red S (ARS) in an interconnected matrix film. In the molecular design of sensing base of the electrode, the electroactive organic units (ARS molecules) present in the ITO/PET-layered (ARS/LDHs)n matrix are involved in electrochemical reactions when exposed to the target molecule (Al3+ ion), so the electrochemical changes of the new formed Al-chelated system are detectable. This type of sensor is used for sensitive and selective detection of Al3+. The minimum sheet resistance, morphology and high electrocatalytic activity of the modified matrix film are obtained in the fifth cycle of LbL assembly technique. In this electrochemical sensor, both electrochemical and optical methods were detected with high sensitivity and selectivity of Al3+, so that in a cyclic voltammetry electrochemical method, the lower detection limit of 10.1 nM with a linear range of [0.2–120 μM] was obtained compared to the fluorescence-based optical method.


2017 ◽  
Vol 29 (1) ◽  
pp. 96-105 ◽  
Author(s):  
Warunee Wattanatanom ◽  
Sireerat Churuchinda ◽  
Pranut Potiyaraj

Purpose The purpose of this paper is to investigate the potential use of the layer-by-layer (LbL) assembly as an intumescent flame retardant for polyester, cotton and their blended fabrics. Design/methodology/approach In this study, polyester (PET), cotton and their blends were applied with the flame retardant coating via the LbL assembly technique. The flame retardancy, melt dripping, thermal properties and morphology of coated polyester fabrics were then examined. Findings The scanning electron micrograph of uncoated and coated fabrics revealed that the LbL assembly coating on the fabric surface was successful. The assessment of the flame retardancy and thermal properties of the coated fabrics showed that the after-flame time and melt dripping during the vertical burning test decreased. The char residue at temperatures ranging from 450 to 800°C during thermogravimetric analysis was enhanced as compared with the uncoated fabric. Furthermore, the morphology of the char residual of coated fabrics was rougher and bulkier than the uncoated fabrics, suggesting the typical behavior of intumescence. Social implications The LbL technique generally uses much fewer chemicals, thus making this flame retardant finishing much more environmentally friendly. It is also expected that these fabrics will show better touch characteristics. These fabrics may be tested for their comfort compared to that of conventional coating to enable their use on an industrial scale. Originality/value This work demonstrated the ability to apply an effective intumescent coating on polyester, cotton and blend fabric. In order to maintain fabric handle property, the Lbl coating technique is also employed.


RSC Advances ◽  
2016 ◽  
Vol 6 (97) ◽  
pp. 94739-94747 ◽  
Author(s):  
Ping Zhang ◽  
Hailong Li ◽  
Jingjing Shi ◽  
Jun Lu

This article reports that the neutral conjugated polymers (NCPs) can also be assembled with exfoliated MgAl-layered double hydroxide (LDH) nanosheets to form the ordered inorganic/organic hybrid ultrathin films via the LbL assembly technique.


2017 ◽  
Vol 214 ◽  
pp. 213-217 ◽  
Author(s):  
Bao Zhang ◽  
Yi Pan ◽  
Hanqing Chen ◽  
Tengfei Liu ◽  
Han Tao ◽  
...  

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 133
Author(s):  
Yu-Che Cheng ◽  
Shu-Lin Guo ◽  
Kun-Da Chung ◽  
Wei-Wen Hu

To sustain gene delivery and elongate transgene expression, plasmid DNA and cationic nonviral vectors can be deposited through layer-by-layer (LbL) assembly to form polyelectrolyte multilayers (PEMs). Although these macromolecules can be released for transfection purposes, their entanglement only allows partial delivery. Therefore, how to efficiently deliver immobilized genes from PEMs remains a challenge. In this study, we attempt to facilitate their delivery through the pretreatment of the external electrical field. Multilayers of polyethylenimine (PEI) and DNA were deposited onto conductive polypyrrole (PPy), which were placed in an aqueous environment to examine their release after electric field pretreatment. Only the electric field perpendicular to the substrate with constant voltage efficiently promoted the release of PEI and DNA from PEMs, and the higher potential resulted in the more releases which were enhanced with treatment time. The roughness of PEMs also increased after electric field treatment because the electrical field not only caused electrophoresis of polyelectrolytes and but also allowed electrochemical reaction on the PPy electrode. Finally, the released DNA and PEI were used for transfection. Polyplexes were successfully formed after electric field treatment, and the transfection efficiency was also improved, suggesting that this electric field pretreatment effectively assists gene delivery from PEMs and should be beneficial to regenerative medicine application.


RSC Advances ◽  
2014 ◽  
Vol 4 (46) ◽  
pp. 24369-24376 ◽  
Author(s):  
Jiemin Zhao ◽  
Xiaoping Wang ◽  
Yanshen Kuang ◽  
Yufeng Zhang ◽  
Xiaowen Shi ◽  
...  

Alginate (ALG)–lysozyme (LZ) beads were fabricated by a cross-linking process. Negatively charged ALG and positively charged LZ were alternately deposited on the positively charged ALG–LZ beads via a layer-by-layer (LBL) self-assembly technique.


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