scholarly journals Dissolvable Polyvinyl-Alcohol Film, a Time-Barrier to Modulate Sample Flow in a 3D-Printed Holder for Capillary Flow Paper Diagnostics

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 343 ◽  
Author(s):  
Dorin Harpaz ◽  
Tim Axelrod ◽  
Alicia Yitian ◽  
Evgeni Eltzov ◽  
Robert Marks ◽  
...  
Keyword(s):  
Polyvinyl Alcohol ◽  
Capillary Flow ◽  
Degree Of Hydrolysis ◽  
The Novel ◽  
Barrier Films ◽  
Critical Areas ◽  
Polyvinyl Alcohol Film ◽  
3D Printed ◽  
Paper Diagnostics ◽  
Higher Sensitivity

Integrating a dissolvable membrane into a sensor allows the control of sample flow, location and duration in critical areas. These time-barrier films stop the flow of samples until the membrane has dissolved, thus, for example, allowing increased exposure time between immunoreagents for the formation of greater numbers of immuno-complexes, ensuring higher sensitivity, reactivity, and helping to reduce false-positive signals. In this study, dissolvable polyvinyl alcohol (PVA) films are used in a 3D-printed sensor holder, which enables film integration without the use of glue. PVA is a synthetic hydrophilic linear polymer, its solubility is dependent on its molecular weight and degree of hydrolysis. Three types of PVAs films were tested herein: (1) PVA 1-Mw: 30–70 K, 87–90% hydrolyzed; (2) PVA 2-Mw: 31–50 K, 98–99% hydrolyzed and (3) PVA 3-Mw: 89–98 K, >99% hydrolyzed. The films were exposed to water in (1) the novel 3D-printed holder and (2) directly immersed into a water droplet. After comparing the time taken to dissolve PVA 1–3 films, PVA 1 films of 5–20% (w/v) are found to be most suitable as time barrier films, due to their optimal dissolution times and physical properties for integration into the customized 3D-printed holder.

Preparation of 3D Printed Chitosan/Polyvinyl Alcohol Double Network Hydrogel Scaffolds

2021 ◽  
pp. 2000398
Author(s):  
Fei Liu ◽  
Wenyu Li ◽  
Hongting Liu ◽  
Teng Yuan ◽  
Yu Yang ◽  
...  
Keyword(s):  
Polyvinyl Alcohol ◽  
Double Network ◽  
Hydrogel Scaffolds ◽  
3D Printed

scholarly journals A rapid and efficient method for the extraction and identification of menaquinones from Actinomycetes in wet biomass

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Fuquan Xie ◽  
Shengxiang Pei ◽  
Xihuang Lin ◽  
Yun Tian ◽  
Gaiyun Zhang
Keyword(s):  
Electron Transport ◽  
Efficient Method ◽  
Efficient Technique ◽  
The Novel ◽  
Species Classification ◽  
Wet Biomass ◽  
Freeze Dried ◽  
Taxonomic Research ◽  
Chloroform Methanol ◽  
Higher Sensitivity

Abstract Background Menaquinones are constituents of prokaryote cell membranes where they play important functions during electron transport. Menaquinone profiles are strongly recommended for species classification when proposing a new Actinomycetes taxon. Presently, the most widely used methods to determine menaquinones are based on freeze-dried cells. Taxonomic research in our lab has revealed that menaquinone concentrations are low for some species of the genus Microbacterium, leading to difficulties in identifying menaquinones. Results Menaquinones extracted using the novel lysozyme-chloroform-methanol (LCM) method were comparable in quality to those obtained using the Collins method, the most widely used method. All tested strains extracted via the LCM method showed higher concentrations of menaquinones than those extracted via the Collins method. For some Microbacterium strains, the LCM method exhibited higher sensitivity than the Collins method, and more trace menaquinones were detected with the LCM method than the Collins method. In addition, LCM method is faster than the Collins method because it uses wet cells. Conclusion The LCM method is a simple, rapid and efficient technique for the extraction and identification of menaquinones from Actinomycetes.

scholarly journals The Influence of Surfactant (SDS) on the Adsorption Properties of Polyvinyl Alcohol and Polyethylene Glycol in an Alumina/Solution System

2002 ◽  
Vol 20 (6) ◽  
pp. 573-582 ◽  
Author(s):  
S. Chibowski ◽  
M. Paszkiewicz ◽  
M. Wiśniewska
Keyword(s):  
Polyethylene Glycol ◽  
Polyvinyl Alcohol ◽  
Adsorption Layer ◽  
Sodium Dodecyl ◽  
Adsorption Properties ◽  
Degree Of Hydrolysis ◽  
Ionic Polymers ◽  
Solution System ◽  
Molecular Weights ◽  
Polymer Surfactant

The influence of sodium dodecyl sulphate (SDS) on the adsorption properties of non-ionic polymers, i.e. polyethylene glycol (PEG) and polyvinyl alcohol (PVA), at the Al2O3/solution interface was studied. Measurements for various molecular weights and for various amounts of functional groups on the polymer macromolecules were undertaken and the results obtained discussed in the light of these variations. Studies of the mutual interactions of the polymer–surfactant system in aqueous solution were helpful in explaining the equilibria involved in the Al2O3/polymer solution system in the presence of SDS. The thickness of the adsorption layer was determined by viscometric methods and the influence of the degree of hydrolysis of PVA on the structure of the adsorption layer demonstrated.

Design and Analysis of a New Mechanism for a Snake Like Robot

2020 ◽  
Author(s):  
Johnathon Garcia ◽  
Kooktae Lee
Keyword(s):  
Power Loss ◽  
Robot Design ◽  
The Novel ◽  
Loss Minimization ◽  
Positive Power ◽  
Unit Distance ◽  
Novel Structure ◽  
3D Printed ◽  
Numerical Minimization ◽  
Novel Design

Abstract In this paper, a novel snake like robot design is presented and analyzed. The structure described desires to obtain a robot that is most like a snake found in nature. This is achieved with the combination of both rigid and soft link structures by implementing a 3D printed rigid link and a soft cast silicone skin. The proposed structure serves to have a few mechanical improvements while maintaining the positives of previous designs. The implementation of the silicone skin presents the opportunity to use synthetic scales and directional friction. The design modifications of this novel design are analyzed on the fronts of the kinematics and minimizing power loss. Minimization of power loss is done through a numerical minimization of three separate parameters with the smallest positive power loss being used. This results in the minimal power loss per unit distance. This research found that the novel structure presented can be effectively described and modeled, such that they could be applied to a constructed model.

Graphene oxide-polyvinyl alcohol film in micro cavity for optical comb filter generation

2020 ◽  
Vol 17 (11/12) ◽  
pp. 787
Author(s):  
Siti Nur Fatin Zuikafly ◽  
Harith Ahmad ◽  
Suhaidi Shafie ◽  
Hong Ngee Lim ◽  
Fauzan Ahmad
Keyword(s):  
Graphene Oxide ◽  
Polyvinyl Alcohol ◽  
Comb Filter ◽  
Polyvinyl Alcohol Film ◽  
Micro Cavity ◽  
Optical Comb Filter
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