Investigation of Optimal Silk Film Thickness in Silk Microneedle Fabrication

2015 ◽  
Vol 752-753 ◽  
pp. 177-181 ◽  
Author(s):  
S. Jiruedee ◽  
W. Luangweera ◽  
B. Sookyu ◽  
K. Patoomvasna ◽  
A. Pimpin ◽  
...  
Keyword(s):  
Film Thickness ◽  
Silk Fibroin ◽  
Adhesion Force ◽  
Low Cost ◽  
Dissolving Microneedles ◽  
Strong Adhesion ◽  
Microneedle Patch ◽  
Fibroin Solution ◽  
Silk Film

Injection is one of the most commonly used methods for delivering drugs or vaccines into human bodies. It is rapid, low-cost and compatible with almost any drugs. However, the major drawbacks of the injection by hypodermic needles are the pain associated with the injection and the disposal of used needles. Microneedles have then received wide attention since they can overcome such drawbacks, especially dissolving microneedles. Recently, silk fibroin has been used to fabricate dissolving silk microneedles for transdermal drug delivery at low temperature. In the fabrication process, the quality of the silk microneedles relies on the solidification of silk fibroin solution. This research aims to study the role of silk fibroin concentration (silk film thickness) in the formation of silk microneedles. In the experiment, silk microneedles were fabricated using various concentrations of silk fibroin solution from 3 to 7% while the volume of the silk fibroin solution was fixed. According to the experimental resuls, it was found that the concentrations of 4-5% were suitable for producing silk microneedles (silk film thickness of 470 μm) while the concentrations of 6-7% caused wrinkles on microneedle patch due to mismatch of upper and lower layers of microneedles. Furthermore, the concentration of 3% had a problem with the demolding step of microneedles since it caused mold damage due to strong adhesion force between microneedles and mold.

Understanding the Role of Chlorine and Ozone to Control Postharvest Diseases in Fruit and Vegetables: A Review

2020 ◽  
Vol 16 (4) ◽  
pp. 455-461
Author(s):  
Gabriela M. Baia ◽  
Otniel Freitas-Silva ◽  
Murillo F. Junior
Keyword(s):  
Chlorine Dioxide ◽  
Broad Spectrum ◽  
Fruits And Vegetables ◽  
Low Cost ◽  
Residual Effects ◽  
Pathogenic Microorganisms ◽  
Postharvest Diseases ◽  
Post Harvest ◽  
By Products

Fruits and vegetables are foods that come into contact with various types of microorganisms from planting to their consumption. A lack or poor sanitation of these products after harvest can cause high losses due to deterioration and/ or pathogenic microorganisms. There are practically no post-harvest fungicides or bactericides with a broad spectrum of action that have no toxic residual effects and are safe. However, to minimize such problems, the use of sanitizers is an efficient device against these microorganisms. Chlorine is the most prevalent sanitizing agent because of its broad spectrum, low cost and well-established practices. However, the inevitable formation of disinfection by-products, such as trihalomethanes (THMs) and haloacetic acids (HAAs), is considered one of the main threats to food safety. Alternative sanitizers, such as chlorine dioxide (ClO2) and ozone, are becoming popular as a substitute for traditional post-harvest treatments. Thus, this review addresses the use of chlorine, chlorine dioxide and ozone emphasizing aspects, such as usage, safe application, spectrum of action and legislation. In order to ensure the quality and safety of final products, the adoption of well-prepared sanitation and sanitation programs for post-harvest fruits and vegetables is essential.

scholarly journals Vanadium doped CaTiO3 cuboids: Role of vanadium in improving the photocatalytic activity

2021 ◽  
Author(s):  
Harsha Bantawal ◽  
Sandhya U. Shenoy ◽  
Denthaje Krishna Bhat
Keyword(s):  
Photocatalytic Activity ◽  
Water Splitting ◽  
Dye Degradation ◽  
Low Cost ◽  
Physicochemical Stability ◽  
Photocatalytic Dye Degradation

CaTiO3 has attracted enormous interest in the field of photocatalytic dye degradation and water splitting owing to its low cost, excellent physicochemical stability and structural tunability. Herein, we have developed...

scholarly journals Do Institutional Transplants Succeed? Regulating Raiffeisen Cooperatives in South India, 1930–1960

2021 ◽  
pp. 1-27
Author(s):  
Maanik Nath
Keyword(s):  
South India ◽  
Financial Regulation ◽  
Low Cost ◽  
Credit Market ◽  
Rural Credit ◽  
Market State ◽  
The Government ◽  
Political Economic ◽  
Rural Credit Market

The government in British-ruled India established cooperative banks to compete with private moneylenders in the rural credit market. State officials expected greater competition to increase the supply of low-cost credit, thereby expanding investment potential for the rural poor. Cooperatives did increase credit supply but captured a small share of the credit market and reported net losses throughout the late colonial and early postcolonial period. The article asks why this experiment did not succeed and offers two explanations. First, low savings restricted the role of social capital and mutual supervision as methods of financial regulation in the cooperative sector. Second, a political-economic ideology that privileged equity over efficiency made for weak administrative regulation.

scholarly journals Current role of ultrasound in hemodialysis access evaluation

2021 ◽  
pp. 112972982110346
Author(s):  
Meola Mario ◽  
Jose Ibeas ◽  
Jan Malik
Keyword(s):  
Turning Point ◽  
Point Of Care ◽  
Low Cost ◽  
Wireless Systems ◽  
Future Perspectives ◽  
Maturation Period ◽  
Surveillance Programs ◽  
Dialysis Nurses

Physical examination (PE) is considered the backbone before vascular access (VA) placement, during maturation period and for follow-up. However, it may be inadequate in identifying suitable vasculature, mainly in comorbid patients, or in detecting complications. This review highlights the advantages of ultrasound imaging to manage VA before placement, during maturation and follow-up. Furthermore, it analyses the future perspectives in evaluating early and late VA complications thank to the availability of multiparametric platforms, point of care of ultrasound, and portable/wireless systems. Technical improvements and low-cost systems should favor the widespread ultrasound-based VA surveillance programs. This significant turning point needs an adequate training of nephrologists and dialysis nurses and the standardization of exams, parameters, and procedures.

scholarly journals Towards a Glass New World: The Role of Ion-Exchange in Modern Technology

2021 ◽  
Vol 11 (10) ◽  
pp. 4610
Author(s):  
Simone Berneschi ◽  
Giancarlo C. Righini ◽  
Stefano Pelli
Keyword(s):  
Ion Exchange ◽  
Communication Networks ◽  
High Speed ◽  
High Performance ◽  
Low Cost ◽  
Modern Technology ◽  
Historical Background ◽  
Wide Range ◽  
Happy Marriage

Glasses, in their different forms and compositions, have special properties that are not found in other materials. The combination of transparency and hardness at room temperature, combined with a suitable mechanical strength and excellent chemical durability, makes this material indispensable for many applications in different technological fields (as, for instance, the optical fibres which constitute the physical carrier for high-speed communication networks as well as the transducer for a wide range of high-performance sensors). For its part, ion-exchange from molten salts is a well-established, low-cost technology capable of modifying the chemical-physical properties of glass. The synergy between ion-exchange and glass has always been a happy marriage, from its ancient historical background for the realisation of wonderful artefacts, to the discovery of novel and fascinating solutions for modern technology (e.g., integrated optics). Getting inspiration from some hot topics related to the application context of this technique, the goal of this critical review is to show how ion-exchange in glass, far from being an obsolete process, can still have an important impact in everyday life, both at a merely commercial level as well as at that of frontier research.

scholarly journals Investigation of the biological activity, mechanical properties and wound healing application of a novel scaffold based on lignin–agarose hydrogel and silk fibroin embedded zinc chromite nanoparticles

RSC Advances ◽  
2021 ◽  
Vol 11 (29) ◽  
pp. 17914-17923
Author(s):  
Reza Eivazzadeh-Keihan ◽  
Hooman Aghamirza Moghim Aliabadi ◽  
Fateme Radinekiyan ◽  
Mohammad Sobhani ◽  
Farzane khalili ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Wound Healing ◽  
Biological Activity ◽  
Silk Fibroin ◽  
Agarose Hydrogel ◽  
Novel Scaffold ◽  
Fibroin Solution ◽  
Zinc Chromite

Given the important aspects of wound healing approaches, in this work, an innovative biocompatible nanobiocomposite scaffold was designed and prepared based on cross-linked lignin–agarose hydrogel, extracted silk fibroin solution, and zinc chromite (ZnCr2O4) nanoparticles.

Preparation and Characterization of Silk Fibroin/Hydroxyapatite Bilayer Scaffolds

2011 ◽  
Vol 415-417 ◽  
pp. 1810-1815 ◽  
Author(s):  
Jian Bing Liu ◽  
Qiang Tang ◽  
Shen Zhou Lu ◽  
Ceng Zhang ◽  
Ming Zhong Li
Keyword(s):  
Silk Fibroin ◽  
Electron Excitation ◽  
Mouse Bone Marrow ◽  
High Porosity ◽  
X Ray Diffraction ◽  
Tissue Engineering Scaffolds ◽  
Molding Method ◽  
Isostatic Compaction ◽  
Fibroin Solution

When the articular cartilage defect accompanies with the subchondral bone defect, using bilayer scaffolds which can integrate with surrounding host cartilage and bone tissue respectively as the tissue engineering scaffolds will be conducive to the repair of tissue defects. This paper reports a new method for preparing bilayer scaffolds. Firstly, hydroxyapatite (HA)/silk fibroin(SF) composite porous materials which have high porosity were prepared by a isostatic compaction molding method, then it was fully immersed in silk fibroin solution, and finally SF/HA bilayer scaffolds were obtained by freeze-drying. The structure of the bilayer scaffolds were investigated through scanning electron microscopy, X-ray diffraction, Fourier transform-infrared spectroscopy, electron excitation spectroscopy and electron microprobe. The results indicated that the upper layer of SF/HA bilayer scaffolds is porous SF component, the under layer is the porous HA/SF composite component and the interface of the two layer is closely connected. Furthermore, mesenchymal stem cells from mouse bone marrow were seeded into the bilayer scaffolds and the results showed that the cells had a well adhesion and growth after culturing for 3 days.

scholarly journals Hematite photoelectrodes for water splitting: evaluation of the role of film thickness by impedance spectroscopy

2014 ◽  
Vol 16 (31) ◽  
pp. 16515 ◽  
Author(s):  
Tânia Lopes ◽  
Luísa Andrade ◽  
Florian Le Formal ◽  
Michael Gratzel ◽  
Kevin Sivula ◽  
...  
Keyword(s):  
Impedance Spectroscopy ◽  
Film Thickness ◽  
Water Splitting

scholarly journals Engineering Mesoporous NiO with Enriched Electrophilic Ni3+ and O− toward Efficient Oxygen Evolution

Catalysts ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 310 ◽  
Author(s):  
Xiu Liu ◽  
Zhi-Yuan Zhai ◽  
Zhou Chen ◽  
Li-Zhong Zhang ◽  
Xiu-Feng Zhao ◽  
...  
Keyword(s):  
Surface Area ◽  
Oxygen Evolution ◽  
Low Cost ◽  
Large Surface Area ◽  
Nucleophilic Attack ◽  
Title Reaction ◽  
Highly Active ◽  
Decomposition Of Water ◽  
Uniform Mesopores

Tremendous efforts have been devoted to develop low-cost and highly active electrocatalysts for oxygen evolution reaction (OER). Here, we report the synthesis of mesoporous nickel oxide by the template method and its application in the title reaction. The as-prepared mesoporous NiO possesses a large surface area, uniform mesopores, and rich surface electrophilic Ni3+ and O− species. The overpotential of meso-NiO in alkaline medium is 132 mV at 10 mA cm−1 and 410 mV at 50 mA cm−1, which is much smaller than that of the other types of NiO samples. The improvement in the OER activity can be ascribed to the synergy of the large surface area and uniform mesopores for better mass transfer and high density of Ni3+ and O− species favoring the nucleophilic attack by OH− to form a NiOOH intermediate. The reaction process and the role of electrophilic Ni3+ and O− were discussed in detail. This results are more conducive to the electrochemical decomposition of water to produce hydrogen fuel as a clean and renewable energy.

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