scholarly journals Synthesis of Europium-doped Fluorapatite Nanorods and Their Multifunctional Biomedical Applications

Author(s):  
Hai Feng Zeng ◽  
Mu Yang Sun ◽  
Su Fan Wu ◽  
Hai Feng Chen

Europium (Eu)-doped fluorapatite (FA) nanorods has a similar biocompatibility with hydroxyapatite (HA) in terms, attracted much attention as cell imaging biomaterials due to their luminescent property. Here, we will discuss the new feature of europium doped fluorapatite (Eu-FA) nanorods as anticancer drug carrier. Eu-FA nanorods was prepared using a hydrothermal method. The morphology, crystal structure, fluorescence and composition are investigated. The specific crystal structure, enabling an effective loading of drug molecules. Doxorubicin (DOX), used as an anticancer model drug, was shown to be effectively loaded onto the surface of the nanorods. The DOX release was fairly pH-dependent, occurring more rapidly at pH 5.5 than pH 7.4 was observed. The intracellular penetration of the DOX-loaded Eu-FA nanorods (Eu-FA/DOX) can be imaged in situ due to the self-fluorescence property. Treatment of melanoma A375 cells with Eu-FA/DOX elicited a more effective apoptosis rate than direct DOX treatment. Overall, Eu-FA show great promise for tracking and treating tumor, may potentially useful as a multifunctional carrier system to effectively load and sustainably deliver drugs.

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Hui Zhou ◽  
Xiaodong Zeng ◽  
Anguo Li ◽  
Wenyi Zhou ◽  
Lin Tang ◽  
...  

AbstractNIR-II fluorophores have shown great promise for biomedical applications with superior in vivo optical properties. To date, few small-molecule NIR-II fluorophores have been discovered with donor-acceptor-donor (D-A-D) or symmetrical structures, and upconversion-mitochondria-targeted NIR-II dyes have not been reported. Herein, we report development of D-A type thiopyrylium-based NIR-II fluorophores with frequency upconversion luminescence (FUCL) at ~580 nm upon excitation at ~850 nm. H4-PEG-PT can not only quickly and effectively image mitochondria in live or fixed osteosarcoma cells with subcellular resolution at 1 nM, but also efficiently convert optical energy into heat, achieving mitochondria-targeted photothermal cancer therapy without ROS effects. H4-PEG-PT has been further evaluated in vivo and exhibited strong tumor uptake, specific NIR-II signals with high spatial and temporal resolution, and remarkable NIR-II image-guided photothermal therapy. This report presents the first D-A type thiopyrylium NIR-II theranostics for synchronous upconversion-mitochondria-targeted cell imaging, in vivo NIR-II osteosarcoma imaging and excellent photothermal efficiency.


2011 ◽  
Vol 364 ◽  
pp. 313-316 ◽  
Author(s):  
Karn Orachai Kullavadee ◽  
Ruktanonchai Uracha ◽  
Siwaporn Meejoo Smith

SLN have shown a great promise as an alternative drug carrier for intravenous and dermal applications. This work focuses on the basic properties of drug-free Compritol® ATO 888 based SLN systems by using cationic surfactant (CPC) and nonionic surfactant (Tween 80). Effects of surfactant on the physical properties of SLNs were investigated in the absence of model drug to avoid the interaction between drug and surfactant. These SLN samples have different particle size, zeta potential and morphology. DSC was used to quantify the crystallinity of SLN systems. It was found that %RI of both SLNs was similar, indicating that types of surfactant did not affect on crystallization of solid lipid. Spherical-like particle was observed with SLN-C, while rod-like particle was found with SLN-T. The results demonstrated that surfactant plays an important role on SLN physical characteristics.


2014 ◽  
Vol 28 ◽  
pp. 131-140 ◽  
Author(s):  
Luiz F. Cotica ◽  
Valdirlei F. Freitas ◽  
Daniel M. Silva ◽  
Karina Honjoya ◽  
Karen Honjoya ◽  
...  

In the search to reduce the side effects, toxicity and assuring the desired effectiveness of the drugs, many efforts has been made to improve specific drugs’ delivery characteristics. Several carrier nanoparticles have been used to assist the drugs incorporation, absorption and transport through the bloodstream. However, most chemical synthesis routes are multistep and time-consuming treatments and, also, many carrier nanoparticles have toxic effects. In this work, we report a simple one-pot approach for the synthesis of CoFe2O4 nanoparticles (20 to 100 nm). The magnetic measurements revealed nanoparticles with a magnetic saturation nearly one third of that for bulk CoFe2O4. In vitro assays showed no hemolytic potential and negligible toxicity. By in vivo experiments using adult male mice we found no potential risk alterations by the nanoparticles administration. Therefore, the CoFe2O4 nanoparticles, synthesized by the current approach, can be a model drug-carrier, which makes them useful for the biomedical applications.


Biomolecules ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 325 ◽  
Author(s):  
Neta Tanner ◽  
Oded Kleifeld ◽  
Iftach Nachman ◽  
Gali Prag

Ubiquitin (Ub) receptors respond to ubiquitylation signals. They bind ubiquitylated substrates and exert their activity in situ. Intriguingly, Ub receptors themselves undergo rapid ubiquitylation and deubiquitylation. Here we asked what is the function of ubiquitylation of Ub receptors? We focused on yeast epsin, a Ub receptor that decodes the ubiquitylation signal of plasma membrane proteins into an endocytosis response. Using mass spectrometry, we identified lysine-3 as the major ubiquitylation site in the epsin plasma membrane binding domain. By projecting this ubiquitylation site onto our crystal structure, we hypothesized that this modification would compete with phosphatidylinositol-4,5-bisphosphate (PIP2) binding and dissociate epsin from the membrane. Using an E. coli-based expression of an authentic ubiquitylation apparatus, we purified ubiquitylated epsin. We demonstrated in vitro that in contrast to apo epsin, the ubiquitylated epsin does not bind to either immobilized PIPs or PIP2-enriched liposomes. To test this hypothesis in vivo, we mimicked ubiquitylation by the fusion of Ub at the ubiquitylation site. Live cell imaging demonstrated that the mimicked ubiquitylated epsin dissociates from the membrane. Our findings suggest that ubiquitylation of the Ub receptors dissociates them from their products to allow binding to a new ubiquitylated substrates, consequently promoting cyclic activity of the Ub receptors.


Nanoscale ◽  
2015 ◽  
Vol 7 (17) ◽  
pp. 7885-7895 ◽  
Author(s):  
Hui Wang ◽  
Guixin Cao ◽  
Zheng Gai ◽  
Kunlun Hong ◽  
Probal Banerjee ◽  
...  

Multifunctional hybrid nanoparticles have been developed for biomedical applications, including magnetic/NIR-responsive drug release, multicolor cell imaging, and enhanced photothermal therapy.


2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 158
Author(s):  
Snežana Ilić-Stojanović ◽  
Ljubiša Nikolić ◽  
Vesna Nikolić ◽  
Slobodan Petrović ◽  
Violeta Oro ◽  
...  

In this study, poly(N-isopropylacrylamide-co-2-hydroxypropyl methacrylate) hydrogels were synthesized using free radical initiated copolymerization method. Four hydrogels with different cross-linker concentrations were prepared. Semi-crystalline, cross-linked copolymer networks were confirmed by FTIR, SEM and XRD analysis. Variation of swelling behaviour was monitored gravimetrically and thermo-responsiveness has been noticed. An application of synthesized thermo-responsive hydrogels as carriers for the modulated release of anti-inflammatory model drug was investigated. Moreover, naproxen loading into these hydrogels was also determined using FTIR, SEM and XRD techniques and release was analyzed using HPLC method at simulated physiological conditions. Swelling kinetic and mechanism of water transport, as well as diffusion of naproxen through the hydrogels were analyzed. Thus, the aim of this work was to study various compositions of obtained hydrogels and their possibility of application as a thermo-responsive carrier for prolonged naproxen release in order to evaluate as a potential candidate for drug carrier in future pharmaceutical applications.


2021 ◽  
pp. 002199832110237
Author(s):  
V Sivaprakash ◽  
R Narayanan

Fabrication of TiO2 nanotubes (NTs) has extensive application properties due to their high corrosion resistant and compatibility with biomedical applications, the synthesis of TiO2 nanotubes over titanium has drawn interest in various fields. The synthesis of TiO2 NTs using novel in-situ step-up voltage conditions in the electrochemical anodization process is recorded in this work. For manufacturing the NTs at 1 hour of anodization, the input potential of 30, 40 and 50 V was selected. With increasing step-up voltage during the anodization process, an improvement in the NTs was observed, favoring corrosion resistance properties. The surface of NTs enhances the structure of the ribs, raising the potential for feedback over time. XRD was used to analyze phase changes, and HR-SEM analyzed surface topography. Impedance tests found that longer NTs improved the corrosion resistance.


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