scholarly journals Bacteriophage Delivery Systems Based on Composite PolyHIPE/Nanocellulose Hydrogel Particles

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2648
Author(s):  
Tilen Kopač ◽  
Ana Lisac ◽  
Rok Mravljak ◽  
Aleš Ručigaj ◽  
Matjaž Krajnc ◽  
...  
Keyword(s):  
Targeted Delivery ◽  
Volume Ratio ◽  
Average Diameter ◽  
Target Site ◽  
Mechanical Stimuli ◽  
Bacteriophage Therapy ◽  
Important Place ◽  
Rapid Release ◽  
Reduced Frequency ◽  
Zero Order Release

The role of bacteriophage therapy in medicine has recently regained an important place. Oral phage delivery for gastrointestinal treatment, transport through the stomach, and fast release in the duodenum is one of such applications. In this work, an efficient polyHIPE/hydrogel system for targeted delivery of bacteriophages with rapid release at the target site is presented. T7 bacteriophages were encapsulated in low crosslinked anionic nanocellulose-based hydrogels, which successfully protected phages at pH < 3.9 (stomach) and completely lost the hydrogel network at a pH above 3.9 (duodenum), allowing their release. Hydrogels with entrapped phages were crosslinked within highly porous spherical polyHIPE particles with an average diameter of 24 μm. PolyHIPE scaffold protects the hydrogels from mechanical stimuli during transport, preventing the collapse of the hydrogel structure and the unwanted phage release. On the other hand, small particle size, due to the large surface-to-volume ratio, enables rapid release at the target site. As a consequence, a fast zero-order release was achieved, providing improved patient compliance and reduced frequency of drug administration. The proposed system therefore exhibits significant potential for a targeted drug delivery in medicine and pharmacy.

scholarly journals Solar-blind ultraviolet photodetector based on vertically aligned single-crystalline β-Ga2O3 nanowire arrays

Nanophotonics ◽  
2020 ◽  
Vol 9 (15) ◽  
pp. 4497-4503
Author(s):  
Liying Zhang ◽  
Xiangqian Xiu ◽  
Yuewen Li ◽  
Yuxia Zhu ◽  
Xuemei Hua ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Light Trapping ◽  
High Surface ◽  
Volume Ratio ◽  
Average Diameter ◽  
Nanowire Arrays ◽  
Etching Technique ◽  
Inductively Coupled ◽  
Solar Blind ◽  
Vertically Aligned

AbstractVertically aligned nanowire arrays, with high surface-to-volume ratio and efficient light-trapping absorption, have attracted much attention for photoelectric devices. In this paper, vertical β-Ga2O3 nanowire arrays with an average diameter/height of 110/450 nm have been fabricated by the inductively coupled plasma etching technique. Then a metal-semiconductor-metal structured solar-blind photodetector (PD) has been fabricated by depositing interdigital Ti/Au electrodes on the nanowire arrays. The fabricated β-Ga2O3 nanowire PD exhibits ∼10 times higher photocurrent and responsivity than the corresponding film PD. Moreover, it also possesses a high photocurrent to dark current ratio (Ilight/Idark) of ∼104 and a ultraviolet/visible rejection ratio (R260 nm/R400 nm) of 3.5 × 103 along with millisecond-level photoresponse times.

scholarly journals Electrosprayed Nanoparticles Based on Hyaluronic Acid: Preparation and Characterization

Technologies ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 71
Author(s):  
Petr Snetkov ◽  
Kseniia Zakharova ◽  
Svetlana Morozkina ◽  
Mikhail Baranov ◽  
Roman Olekhnovich ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Targeted Delivery ◽  
Drug Delivery Systems ◽  
Average Diameter ◽  
Delivery Systems ◽  
Polymer Carriers ◽  
Modern Drug ◽  
Subsequent Application ◽  
Pharmaceutical Agents ◽  
Targeted Delivery Systems

Modern drug delivery systems demand the development of targeted polymer-carriers with the set of obligatory requirements. Thus, such capsules must have total biocompatibility, biodegradability, and possess non-allergenic, and non-tumorigenic properties. Hyaluronic acid (HA), as a natural linear polysaccharide that is included in the pericellular and extracellular matrixes, satisfies all these demands in the best possible way. In this study, the biopolymer nanoparticles with an average diameter of 300 nm were successfully obtained from aqueous HA solutions by electrospraying technique and characterized. Due to the presence of active functional groups in the structure of HA, such polymer particles can incorporate various pharmaceutical agents. This finding expands the investigation and subsequent application of drug-loaded nanoparticles based on HA as challenging and advanced targeted delivery systems.

Preparation and Evaluation of a Photo-Fenton Heterogeneous Catalyst: Spinel-Typed ZnFe2O4

2012 ◽  
Vol 550-553 ◽  
pp. 329-335 ◽  
Author(s):  
Ping Li ◽  
Huan Yan Xu ◽  
Xue Li ◽  
Wei Chao Liu ◽  
Yan Li
Keyword(s):  
Heterogeneous Catalyst ◽  
Sol Gel ◽  
Volume Ratio ◽  
Average Diameter ◽  
Egg White ◽  
Zinc Nitrate ◽  
Complexing Agent ◽  
Ferric Nitrate ◽  
Irregular Shapes ◽  
Fenton System

In this study, spinel-typed ZnFe2O4 was synthesized through Sol-Gel method, using fresh egg white as a complexing agent, and characterized by XRD and SEM. Then, the synthesized sample was used as the photo-Fenton heterogeneous catalyst for the discoloration of methyl orange (MO) in solution. The XRD results show that the synthesized sample was pure, only with the spinel structure, when the volume ratio of the fresh egg white/ferric nitrate/zinc nitrate was 2:2:1. And the lowest sintered temperature to obtain the single-phase ZnFe2O4 was 500°C. The SEM results reveal that the ZnFe2O4 crystalline grains presented irregular shapes and desultorily aggregated together, with a average diameter of 150-250nm. The experimental results show that MO could be efficiently discolored in photo-Fenton system of ZnFe2O4 and H2O2, under UV irradiation. MO discoloration ratio increased as H2O2 dosage increasing. The optimum dosage of ZnFe2O4 was 1g/L in this study. With the MO initial concentration increasing, MO discoloration ratio decreased. The ZnFe2O4 sample obtained at 500°C exhibited the optimum MO discoloration ratio. Finally, the mechanism for MO discoloration in the photo-Fenton system was discussed.

scholarly journals Investigation of the Larvicidal Potential of Silver Nanoparticles againstCulex quinquefasciatus: A Case of a Ubiquitous Weed as a Useful Bioresource

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Elijah T. Adesuji ◽  
Omolara O. Oluwaniyi ◽  
Haleemat I. Adegoke ◽  
Roshila Moodley ◽  
Ayomide H. Labulo ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Electron Microscope ◽  
Volume Ratio ◽  
Average Diameter ◽  
Environmentally Benign ◽  
X Ray ◽  
Transmission Electron ◽  
Aqueous Leaf Extract ◽  
Temperature Time ◽  
Filariasis Vector

Biosynthesized silver nanoparticles (AgNPs) usingCassia hirsutaaqueous leaf extract were reported in this study. The synthesis was optimized by measuring various parameters such as temperature, time, volume ratio, and concentration. The surface plasmon resonance at 440 nm for 30°C and 420 nm for both 50°C and 70°C measured using the UV-Vis spectrophotometer confirmed the formation of AgNPs synthesized usingC.hirsuta(CAgNPs). The functional groups responsible for the reduction and stabilization of the NPs were identified using Fourier Transform Infrared (FTIR). The morphology, size, and elemental composition of the NPs were obtained using scanning electron microscope (SEM), transmission electron microscope (TEM), and energy dispersive X-ray spectroscopy (EDX). X-ray diffractometer was used to identify the phases and crystallinity of CAgNPs. Crystalline spherical NPs with average diameter of 6.9 ± 0.1 nm were successfully synthesized. The thermal analysis of CAgNPs was observed from DSC-TGA. The larvicidal results against the different larva instar stage ofCulex quinquefasciatusgave LC50= 4.43 ppm and LC90= 8.37 ppm. This is the first study on the synthesis of AgNPs usingC.hirsutaand its application against lymphatic filariasis vector. Hence, it is suggested that theC.hirsutasynthesized AgNPs would be environmentally benign in biological control of mosquito.

Dynamic Responses of Partially Cavitated Hydrofoil Cascade to Axial Gust in Bubbly Water

1984 ◽  
Vol 106 (3) ◽  
pp. 312-318
Author(s):  
Tetsuo Nishiyama ◽  
Hideya Nishiyama
Keyword(s):  
Water Conservation ◽  
Pressure Rise ◽  
Volume Ratio ◽  
Gain Factor ◽  
Dynamic Responses ◽  
Cavity Model ◽  
Cavity Pressure ◽  
Reduced Frequency ◽  
The Mean ◽  
Unsteady Discharge

A method for analysis by singularity representations is presented for dynamic responses of partially cavitated hydrofoil cascade to axial gust in bubbly water. Conservation laws of mass and momentum are applied to take account of the unsteady parts of cavity area, cavity termination thickness, and cavity pressure for unsteady partial cavity model. Also, the cavitation compliance and mass flow gain factor obtained from the cavity model determined are considered in relations to cavity length, reduced frequency, and air volume ratio. Comparisons of the mean unsteady pressure rise and unsteady discharge difference are also made with the available former results.

Electrospinning and Characterization of Novel Opuntia ficus-indica Mucilage Biomembrane

2012 ◽  
Vol 1480 ◽  
Author(s):  
Sylvia W. Thomas ◽  
Norma A. Alcantar ◽  
Yanay Pais
Keyword(s):  
Acetic Acid ◽  
Acid Solution ◽  
Acetic Acid Solution ◽  
Volume Ratio ◽  
Average Diameter ◽  
Low Molecular Weight ◽  
Opuntia Ficus Indica ◽  
Force Microscopy ◽  
Atomic Force

ABSTRACTOpuntia ficus-indica (Ofi) cactus non-gelling (NE) mucilage nanofibers were electrospun with acetic acid solution and polyvinyl alcohol (PVA) as a polymer. The best fiber coverage was achieved with an aqueous 50% acetic acid solution and 9% low molecular weight PVA at a 70:30 PVA:Mucilage volume ratio. Other volume ratios (30:70 and 50:50) produced beads and other deformities. Fibers were formed with an average diameter of 180nm as measured by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Favorable electrospinning conditions were used to fabricate a 1 cm x 1 cm Ofi nanofiber biomembrane. Heat flow (W/g) versus temperature peaks ranged from 214 – 222°C, which is comparable to endothermic peak ranges observed for crystalline PVA. This could possibly further indicate some form of crystallinity within the Ofi nanofiber membrane. The electrospun process used precursors that were biodegradable, non-toxic, and sustainable to optimize the mucilage nanofiber formation, which will help enhance the potential performance of the Ofi nanofiber biomembrane in filtration and sensory systems.

scholarly journals Emerging nanomaterials for dental treatments

2020 ◽  
Vol 4 (6) ◽  
pp. 613-625
Author(s):  
Zi Hong Mok ◽  
Gordon Proctor ◽  
Maya Thanou
Keyword(s):  
Targeted Delivery ◽  
Volume Ratio ◽  
Stem Cell Differentiation ◽  
Bioactive Molecules ◽  
Dental Composites ◽  
Small Particle Size ◽  
Tooth Structure ◽  
Dental Tissues ◽  
Intense Action ◽  
Anti Inflammation

The emergence of nanomaterials for dental treatments is encouraged by the nanotopography of the tooth structure, together with the promising benefits of nanomedicine. The use of nanoparticles in dentistry, also termed as ‘nanodentistry', has manifested in applications for remineralisation, antimicrobial activity, local anaesthesia, anti-inflammation, osteoconductivity and stem cell differentiation. Besides the applications on dental tissues, nanoparticles have been used to enhance the mechanical properties of dental composites, improving their bonding and anchorage and reducing friction. The small particle size allows for enhanced permeation into deeper lesions, and reduction in porosities of dental composites for higher mechanical strength. The large surface area to volume ratio allows for enhanced bioactivity such as bonding and integration, and more intense action towards microorganisms. Controlled release of encapsulated bioactive molecules such as drugs and growth factors enables them to be delivered more precisely, with site-targeted delivery for localised treatments. These properties have benefitted across multiple fields within dentistry, including periodontology and endodontics and reengineering of dental prosthetics and braces. This review summarises the current literature on the emerging field of nanomaterials for dental treatments.

Needleless electrospun mats based on polyamidoamine dendritic polymers for encapsulation of essential oils in personal respiratory equipment

2021 ◽  
pp. 152808372110481
Author(s):  
Maryam Mounesan ◽  
Somaye Akbari ◽  
Bogumil E Brycki
Keyword(s):  
Volume Ratio ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Dust Particles ◽  
High Porosity ◽  
Dendritic Polymers ◽  
Tea Tree ◽  
Electrospinning Method ◽  
Oil Mist ◽  
Pass Through

The ever-increasing concern of air pollution triggered by broad-spreading contagious disease, bioterrorism, and release of dust particles in the air is targeted to be addressed in this paper by developing a novel personal respiratory equipment (PRE). For this purpose, polyamidoamine dendritic polymers (PAMAMs) were utilized not only for encapsulating tea tree essential oil (TEO), an antimicrobial material, but also for battling against perilous bioaerosols. Furthermore, TEO is encapsulated inside both PAMAM and polyacrylonitrile (PAN) electrospun nanofibers. Results clarified that electrospun samples containing both TEO and PAMAM possess thinner nanofibers with 440 nm reduction in their average diameter, and pursuantly higher filtration efficiency against both NaCl and paraffin oil mist particles about 98% and well above 99%, respectively. Herein, the electrospinning method is employed first for high porosity, enhanced surface area to volume ratio, and interconnected pores of resulted nanofibers, which are strongly useful in capturing the dust and allowing more air to flow and pass through, and creating a good air circulation. Second, the synergistic effect of using both electrospinning and PAMAM as the host molecules is also a promising approach for addressing the volatility of fragrances by producing a controlled release of TEO.

Enhanced Anti-tumor Activity of Drug through pH-Triggered Release and Dual Targeting by Calcium Phosphate-Covered Mesoporous Silica Vehicles

2021 ◽  
Author(s):  
Juan Liu ◽  
Xixue Hu ◽  
Shubin Jin ◽  
Xing-Jie Liang ◽  
Xiaowei Ma
Keyword(s):  
Controlled Release ◽  
Calcium Phosphate ◽  
Targeted Delivery ◽  
Antitumor Drugs ◽  
Triggered Release ◽  
Dual Targeting ◽  
Rapid Release ◽  
Main Factors ◽  
Anti Tumor Activity

Rapid release and clearance of antitumor drugs in vivo are the main factors to evade the effectiveness of chemotherapeutics. Targeted delivery and controlled release of drugs are the most pressing...

Uniform Nano/Micron-Sized ZnO Spheres with Controllable Diameter

2012 ◽  
Vol 496 ◽  
pp. 268-271
Author(s):  
Ji Hang Cheng ◽  
Shuang Xu ◽  
Chang Hong Ding
Keyword(s):  
Hydrothermal Method ◽  
Absorption Spectra ◽  
Volume Ratio ◽  
Average Diameter ◽  
Absorption Peak ◽  
Nano Particles ◽  
Visible Absorption ◽  
Uv Visible

Novel uniform nano/micron-sized ZnO spheres assembled from the aggregation of nano-particles have been synthesized by hydrothermal method. It was observed that ZnO spheres with controllable diameter were obtained when various volume ratios of triethanolamine (TEA) to H2O were used. Increasing the volume ratio of TEA to H2O could result in the formation of loosely packed ZnO spheres. The UV-visible absorption spectra show that the absorption peak red-shifts with the increasing average diameter of the spheres.

Sign in / Sign up

Export Citation Format

Share Document