scholarly journals Polyurethane-functionalized starch nanocrystals as anti-tuberculosis drug carrier

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shivang K. Desai ◽  
Dhananjoy Mondal ◽  
Smritilekha Bera
Keyword(s):  
Drug Carrier ◽  
Drug Loading ◽  
Morphological Properties ◽  
Burst Release ◽  
Average Particle ◽  
Particle Sizes ◽  
First Line ◽  
Transmission Electron ◽  
H37rv Strain ◽  
Starch Nanocrystals

AbstractStudies related to loading ability and delivery of clinically used first-line anti-tuberculosis drugs (ATDs) such as isoniazid, rifampicin, pyrazinamide and streptomycin on the surface of starch-derived bulk and nanopolyurethanes (SBPUs and SNPUs) as drug delivery systems (DDS) have been focused to minimise or remove the drug-associated adverse effects. The efficiencies of nanopolyurethanes obtained from the differently substituted cyclic aliphatic and aromatic isocyanates have been studied for drug loading and release purposes. Different advanced instrumental techniques analysed the structural and morphological properties, thermal stability and crystallinity of the starch nanopolyurethans. Average particle sizes ranging from 27.35–42.38 nm to 126.89–218.60 nm for starch nanopolyurethans, SNPU3i and SNPU4i, respectively, were determined by high-resolution transmission electron microscopy. Similarly, the loading efficiency of ATDs to the surfaces of SNPUs and SBPUs was observed in the range of 60–97% while ATDs-loaded SNPUs showed a sustainable release profile for all ATDs except for streptomycin. However, most SBPUs provided burst-release for all the above-mentioned ATDs in pH-dependent studies. The anti-tuberculosis assay against the Mycobacterium tuberculosis H37Rv strain revealed that streptomycin-loaded SNPU4i and isoniazid-loaded SNPU7i are approximately 42 and 7 times more active than the native streptomycin and isoniazid, respectively.

scholarly journals Fabrication and Characterization of Strontium-Substituted Hydroxyapatite-CaO-CaCO3 Nanofibers with a Mesoporous Structure as Drug Delivery Carriers

Pharmaceutics ◽  
2018 ◽  
Vol 10 (4) ◽  
pp. 179 ◽  
Author(s):  
Shiao-Wen Tsai ◽  
Wen-Xin Yu ◽  
Pai-An Hwang ◽  
Sheng-Siang Huang ◽  
Hsiu-Mei Lin ◽  
...  
Keyword(s):  
Drug Carrier ◽  
Drug Loading ◽  
Average Pore Size ◽  
Sol Gel ◽  
Mesoporous Structure ◽  
Drug Carriers ◽  
Burst Release ◽  
Doping Amount ◽  
Sem Images ◽  
Average Pore

Hydroxyapatite (HAp) is the main inorganic component and an essential part of hard bone and teeth. Due to its excellent biocompatibility, bioactivity, and osteoconductivity, synthetic HAp has been widely used as a bone substitute, cell carrier, and therapeutic gene or drug carrier. Recently, numerous studies have demonstrated that strontium-substituted hydroxyapatite (SrHAp) not only enhances osteogenesis but also inhibits adipogenesis in mesenchymal stem cells. Mesoporous SrHAp has been successfully synthesized via a traditional template-based process and has been found to possess better drug loading and release efficiencies than SrHAp. In this study, strontium-substituted hydroxyapatite-CaO-CaCO3 nanofibers with a mesoporous structure (mSrHANFs) were fabricated using a sol–gel method followed by electrospinning. X-ray diffraction analysis revealed that the contents of CaO and CaCO3 in the mSrHANFs decreased as the doping amount of Sr increased. Scanning electron microscopy (SEM) images showed that the average diameter of the mSrHANFs was approximately 200~300 nm. The N2 adsorption–desorption isotherms demonstrated that the mSrHANFs possessed a mesoporous structure and that the average pore size was approximately 20~25 nm. Moreover, the mSrHANFs had excellent drug- loading efficiency and could retard the burst release of tetracycline (TC) to maintain antibacterial activity for over 3 weeks. Hence, mSrHANFs have the potential to be used as drug carriers in bone tissue engineering.

scholarly journals Mild Hydrothermal Synthesis of Ni–Cu Nanoparticles

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
G. H. Mohamed Saeed ◽  
S. Radiman ◽  
S. S. Gasaymeh ◽  
H. N. Lim ◽  
N. M. Huang
Keyword(s):  
Sodium Dodecyl ◽  
Hydrothermal Condition ◽  
Average Particle ◽  
Particle Sizes ◽  
Cu Nanoparticles ◽  
Cu Alloy ◽  
Transmission Electron ◽  
Metal Metal ◽  
Paramagnetic Behaviour ◽  
Triton X

Magnetic Ni-rich Ni–Cu nanoparticles with Ni : Cu mass ratio (S) of 2.0 and 2.6 were prepared using a mixture of polyoxyethylene (10) isooctylphenyl ether (Triton X-100) and sodium dodecyl sulfate (SDS) in a mild hydrothermal condition at 95ºC. X-ray diffractometry (XRD) showed that the nanoparticles prepared atS=2.0possessed Ni–Cu alloy characteristic whereas the characteristic was absent atS=2.6. The XRD data was enhanced by Fourier transform infrared spectroscopy (FTIR) which exhibited metal-metal (Ni–Cu) band at 455 cm−1. Based on transmission electron microscopy (TEM), the average particle sizes for the nanoparticles prepared atS=2.0and 2.6 were in the range of 19–23 nm. The as-prepared nanoparticles exhibited paramagnetic behaviour measured using a vibrating sample magnetometer (VSM) and the specific saturation magnetization decreased at the higher concentration of Ni.

Rapid Preparation of V2O3 and VN Nanocrystals by Ammonolysis of the Precursor VOC2O4•H2O

2011 ◽  
Vol 194-196 ◽  
pp. 660-664 ◽  
Author(s):  
Hua Lin ◽  
Bo Wan Tao ◽  
Qing Li ◽  
Yan Rong Li
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Average Particle ◽  
Particle Sizes ◽  
Tubular Furnace ◽  
Rapid Preparation ◽  
X Ray ◽  
Transmission Electron ◽  
Thermal Ammonolysis

V2O3 and VN nanocrystals have been conveniently synthesized from thermal ammonolysis of the precursor VOC2O4•H2O in a resistance tubular furnace at 500°С and 780°С for 30 min, respectively. The products were characterized by X-ray diffractometer (XRD)、X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) techniques. The average particle sizes of V2O3 and VN are both in the ranges of 20~35 nm. The evolution from precursor to hexagonal V2O3 and then to cubic VN was explored. The crucial factors，such as the reaction temperature and time，have also been discussed.

Synthesis of n-Hexadecylphosphonic Acid-Coated Monodisperse Fe3O4 Superparamagnetic Nanoparticles

2012 ◽  
Vol 512-515 ◽  
pp. 170-173
Author(s):  
Xue Song Tang ◽  
Ming Li
Keyword(s):  
Crystal Structure ◽  
Particle Size ◽  
Drug Loading ◽  
Average Particle Size ◽  
Superparamagnetic Nanoparticles ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Cubic Crystal ◽  
Transmission Electron ◽  
Potential Applications

Monodisperse Fe3O4 Superparamagnetic Nanoparticles Were Synthesized in N-Hexadecylphosphonic Acid/ Cyclohexane/ Water/ Ethanol Microemulsion under Solvothermal Conditions at 100°C. the Crystal Structure and Particle Size of Synthesized Fe3O4 Were Observed by X-Ray Diffraction (XRD) as Well as Transmission Electron Microscopy (TEM). the Results Show that the Nanoparticles Have a Cubic Crystal System and a Average Particle Size of about 10nm. each Nanoparticle Has a Single Crystal Structure. the Surface Chemistry of Synthesized Fe3O4 Nanoparticles Was Characterized by Fourier Transform Infrared Spectroscopy (FTIR), Indicating that the Nanoparticles Were Covered by a Layer of N-Hexadecylphosphonic Acid, which Made the Nanoparticles Totally Lipophilic. Magnetic Properties of the Nanoparticles Were Investigated by Using Vibrating Sample Magnetometer (VSM). the Result Reveals that the Saturation Magnetization (Ms) of the Nanoparticles Is Higher than 40 Emu/G and the Coercive Force Is near to 0. the Monodisperse Fe3O4 Nanoparticles Have Superparamagnetic Property and May Find Potential Applications in many Fields, such as Ferrofluids, Drug Loading and Release, Selective Biomolecular Separation and MRI.

Yttria-based nano-sized powders: A new class of fractal materials obtained by combustion synthesis

2000 ◽  
Vol 15 (3) ◽  
pp. 586-589 ◽  
Author(s):  
Giuliano Fagherazzi ◽  
Stefano Polizzi ◽  
Marco Bettinelli ◽  
Adolfo Speghini
Keyword(s):  
Combustion Synthesis ◽  
Average Particle ◽  
Luminescent Materials ◽  
Particle Sizes ◽  
Saxs Data ◽  
New Class ◽  
X Ray Scattering ◽  
Transmission Electron ◽  
Fractal Materials ◽  
First Time

Small-angle x-ray scattering (SAXS) technique has been used to investigate nano-sized powders of Y2O3, Y1.8Er0.2O3, and Y1.8Nd0.2O3, obtained by means of combustion synthesis. The results show that the powders have a mass-fractal behavior, with fractal dimension, Df, in the 1.7–1.8 range, and average particle sizes in the 20–30-nm range. These results are supported by transmission electron microscope observations. Moreover, from SAXS data, it has been possible to establish a narrow particle size polydispersity, as well as the presence of particle-diffuse or “fuzzy” interfaces. These results show, for the first time, the fractal behavior of materials prepared by combustion synthesis and are in agreement with a recently developed model. The nanostructural features are discussed within the framework of the peculiar optical properties of the doped luminescent materials.

scholarly journals Design and evaluation of albumin nanoparticles for the delivery of a novel β-tubulin polymerization inhibitor

2021 ◽  
Vol 24 ◽  
pp. 344-362
Author(s):  
Alessandra Spada ◽  
Jaber Emami ◽  
Foroughalsadat Sanaee ◽  
Maral Aminpour ◽  
Igor, M Paiva ◽  
...  
Keyword(s):  
Drug Loading ◽  
In Vitro Release ◽  
Free Drug ◽  
Release Time ◽  
Burst Release ◽  
Average Particle ◽  
Albumin Nanoparticles ◽  
Significant Difference ◽  
Vitro Release

Purpose: The ultimate goal of this study is to develop a novel delivery system for a new potent cytotoxic compound, CCI-001, with anti-b tubulin activity, so that the drug can be effectively administered and at the same time its harmful side effects can be reduced. Methods: In the current study, CCI-001 was loaded into serum albumin (SA), using a modified desolvation method, generating CCI-001-SA nanoparticles. Both bovine and human SA were used for the encapsulation of this drug candidate. Optimum conditions for drug loading were achieved when already formed and crosslinked albumin nanoparticles were incubated overnight at 37°C with CCI-001 solutions. The CCI-001-loaded albumin nanoparticles were assessed for average particle diameter and polydispersity, zeta potential, drug loading, in vitro release, morphology and cell toxicity against SW620 and HCT116 colorectal cancer cells. Results: The spherical nanoparticles obtained were negatively charged (~ -30 mV) and had an average diameter of ~ 130 nm, with a narrow size distribution. The in vitro release of CCI-001 from the albumin nanoparticles showed a sustained release pattern over 24 hours without any initial burst release, compared to the fast release of the free drug under experimental conditions. No difference between the SA from the two species in terms of CCI-001 loading was observed. However, a significant difference was observed between the release profiles of CCI-001 from drug-loaded HSA and drug-loaded BSA nanoparticles with HSA nanoparticles showing slower drug release (mean release time, MRT, values of 5.14 ± 0.33 h and 6.88 ± 0.15 h for BSA-NPs and HSA-NPs, respectively, P < 0.01). Cellular toxicity studies showed higher cytotoxicity for CCI-001-SA compared to the free drug (IC50s of 0.62 ± 0.31 nM vs 2.06 ± 0.29 nM in SW620 cells and 0.9 ± 0.1 nM vs 4.2 ± 0.2 nM in HCT116 cells, for CCI-001-HSA NPs and free drug, respectively). Therefore, despite the low drug content level in the HSA nanoparticles of CCI-001, the formulation provides relevant concentrations for further in vivo studies in animal models due to high drug potency. Conclusions: The data support the potential use of albumin as a nanocarrier for CCI-001 in biological systems.

Solvothermal Synthesis and Photoluminescence of Rod-Like YVO4:Dy 3+ Nanocrystals

2011 ◽  
Vol 415-417 ◽  
pp. 633-636 ◽  
Author(s):  
Jia Gui Li ◽  
Guo Cong Liu ◽  
Da Wen Liang
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Powder Diffraction ◽  
Solvothermal Synthesis ◽  
Photoluminescence Spectroscopy ◽  
Yellow Emission ◽  
Average Particle ◽  
Particle Sizes ◽  
X Ray ◽  
Transmission Electron

YVO 4:Dy 3+ nanorods were synthesized via a solvothermal route at 150°C. The as-prepared products were investigated using the X-ray powder diffraction, transmission electron microscopy, and photoluminescence spectroscopy. The results showed that the average particle sizes of these nanorods are from 20 to 600 nm. The photoluminescence (PL) measurements showed that these nanorods exhibited improved photoluminescence compared with YVO 4:Dy 3+ irregular nanoparticles. It is found that the appropriate calcinations temperature is helpful to improve the yellow emission.

scholarly journals Preparation of a novel ginkgolide B niosomal composite drug

2020 ◽  
Vol 18 (1) ◽  
pp. 1064-1074
Author(s):  
Juntong Zhou ◽  
Xiao Wu ◽  
Zhanhong Zhao ◽  
Zhenpeng Wang ◽  
Shumu Li ◽  
...  
Keyword(s):  
Particle Size ◽  
Brain Tissue ◽  
Loading Rate ◽  
Drug Carrier ◽  
Drug Loading ◽  
Water Soluble ◽  
Average Particle ◽  
Ginkgolide B ◽  
Mass Ratio ◽  
Hydrophilic Lipophilic Balance

AbstractGinkgolide B (GB) and Puerarin (Pue) are active pharmaceutical ingredients for the treatment of Parkinson’s disease (PD); however, both are poorly water-soluble, which limits their bioavailability. The present study used the niosome vesicle encapsulation technique to prepare a novel GB composite drug. The conditions for GB–Pue niosomal complex preparation were as follows: a hydration temperature of 60°C, a hydrophilic–lipophilic balance of 10.5, a drug–carrier mass ratio of 8:100, and a surfactant–cholesterol mass ratio of 1.5:1. The niosomal complex suspension was uniformly distributed and milky white in color, with no stratification over a duration of 1 month. It had an average particle size of 187.3 nm, a particle-size distribution of 0.237, a GB encapsulation efficiency (EE) of 68.2%, a GB drug-loading rate of 90.1%, a Pue EE of 40.5%, and a Pue drug-loading rate of 83.3%. The optimal storage temperature for the niosomal complex suspension was 4°C. Following an intravenous injection of the niosomal complex suspension into the rat tail, the area under the curve (AUC) from 0 to 4 h was 54.1 h µg mL−1, with a mean residence time (MRT) of 0.96 h, a distribution half-life (T1/2α) of 0.195 h, and a total clearance of 0.003 L h−1 kg−1. The AUC and MRT of the composite prescription were 1.1- and 1.4-times those of the commercial injection, respectively, showing significantly increased sustained release and bioavailability. Moreover, the distribution of GB in the brain tissue was 1.8-times that of the commercial injection. In conclusion, the novel GB niosomal composite drug, with excellent stability, improved pharmacokinetics, and brain tissue distribution, demonstrates great potential for the delivery of GB and Pue for PD therapeutics.

A High Resolution Study of Alumina Supported Iridium Catalysts

1980 ◽  
Vol 38 ◽  
pp. 202-203
Author(s):  
C. Stoeckert ◽  
B. Etherton ◽  
M. Beer ◽  
J. Gryder
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Metal Particles ◽  
Optical Transfer Function ◽  
Particle Sizes ◽  
Iridium Catalysts ◽  
Transmission Electron ◽  
Optical Transfer ◽  
Conventional Transmission Electron Microscope ◽  
Resolution Study

The interpretation of the activity of catalysts requires information about the sizes of the metal particles, since this has implications for the number of surface atoms available for reaction. To determine the particle dimensions we used a high resolution STEM1. Such an instrument with its simple optical transfer function is far more suitable than a conventional transmission electron microscope for the establishment of particle sizes. We report here our study on the size and number distribution of Ir particles supported on Al2O3 and also examine simple geometric models for the shape of Ir particles.

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