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Jing-Min Liu, Yao-Yao Liu, Dong-Dong Zhang, Guozhen Fang, Shuo Wang
The rise of multimodal nanoprobes has promoted the development of new methods to explore multiple molecular targets simultaneously, or to combine various bioimaging tools in one assay to more clearly delineate localization and expression of bio-markers. Persistent luminescence nanophosphors (PLNPs) have been qualified as the promising contrast agent for in vivo imaging. The easy surface modification and proper nanostructure design strategy would favor the fabrication of PLNPs based multi-functional nanoprobes for biological application...
October 19, 2016: ACS Applied Materials & Interfaces
Priten Savaliya, Anuj Dhawan
Employing finite difference time domain simulations, we demonstrate that electromagnetic field enhancement is substantially greater for tapered optical fibers with plasmonic nanostructures present on their tips as compared with non-tapered optical fibers having those plasmonic nanostructures, or with tapered optical fibers without the plasmonic nanostructures. We also carried out fabrication of plasmonic nanostructures on optical fiber tips.
October 1, 2016: Optics Letters
Laure Mercier de Lépinay, Benjamin Pigeau, Benjamin Besga, Pascal Vincent, Philippe Poncharal, Olivier Arcizet
The miniaturization of force probes into nanomechanical oscillators enables ultrasensitive investigations of forces on dimensions smaller than their characteristic length scales. It also unravels the vectorial character of the force field and how its topology impacts the measurement. Here we present an ultrasensitive method for imaging two-dimensional vectorial force fields by optomechanically following the bidimensional Brownian motion of a singly clamped nanowire. This approach relies on angular and spectral tomography of its quasi-frequency-degenerated transverse mechanical polarizations: immersing the nanoresonator in a vectorial force field not only shifts its eigenfrequencies but also rotates the orientation of the eigenmodes, as a nanocompass...
October 17, 2016: Nature Nanotechnology
Lei Bao, Lin Ding, Jingjing Hui, Huangxian Ju
A lysosome-accessing nanoprobe is designed for recognition of lysosomal neuraminidases (Lyso-Neus), which can cleave the 4-methylumbelliferone moieties of the substrate from the nanoprobe, and lead to the escape of the moieties from acidic lysosomes into the neutral cytosol assisted by cationic poly(ethyleneimine) to light up the pH-responsive fluorescence for visual detection and dynamic tracking of Lyso-Neu activity in living cells.
October 14, 2016: Chemical Communications: Chem Comm
Yamei Li, Nan Wang, Zhanhang He
Nitrogen-doped fluorescent carbon quantum dots (CQDs) was prepared by gas assisted method using cellulose as precursors under ammonia atmosphere, which not only exhibited excellent photoluminescent properties, but also showed highly selective and sensitive detection of mercury ion. The nitrogen-doped CQDs displayed excitation wavelength dependent fluorescent behavior with outstanding dispersibility. Moreover, they exhibited high tolerance to various external conditions, such as storage time, pH value and ionic strength...
October 12, 2016: Environmental Technology
Amit Kumar, Sungi Kim, Jwa-Min Nam
The localized surface plasmon resonance of metal nanopar-ticles is the collective oscillation of electrons on particle surface, and is a particle composition, morphology and cou-pling-dependent property. Plasmonic engineering deals with highly precise formation of the targeted nanostructures with targeted plasmonic properties (e.g., electromagnetic field distribution and enhancement) via controlled synthetic, assembling and atomic/molecular tuning strategies. These plasmonically engineered nanostructures (PENs) have a variety of unique and beneficial physical, chemical and bio-logical properties including optical signal enhancement, catalytic property and local temperature-tuning photother-mal property...
October 10, 2016: Journal of the American Chemical Society
G Veronesi, A Deniaud, T Gallon, P-H Jouneau, J Villanova, P Delangle, M Carrière, I Kieffer, P Charbonnier, E Mintz, I Michaud-Soret
Silver nanoparticles (AgNPs) can enter eukaryotic cells and exert toxic effects, most probably as a consequence of the release of Ag(+) ions. Due to the elusive nature of Ag(+) ionic species, quantitative information concerning AgNP intracellular dissolution is missing. By using a synchrotron nanoprobe, silver is visualized and quantified in hepatocytes (HepG2) exposed to AgNPs; the synergistic use of electron microscopy allows for the discrimination between nanoparticular and ionic forms of silver within a single cell...
September 29, 2016: Nanoscale
Lang Rao, Zhaobo He, Qian-Fang Meng, Ziyao Zhou, Lin-Lin Bu, Shi-Shang Guo, Wei Liu, Xing-Zhong Zhao
Upconversion nanoparticles (UCNPs), with fascinating optical and chemical features, are a promising new generation of fluorescent probes. Although UCNPs have been widely used in diagnosis and therapy, there is an unmet need for a simple and effective surface engineering method that can produce cancer-targeting UCNPs. Here, we show that by coating particles with macrophage membranes, it becomes possible to utilize the adhesion between macrophages and cancer cells for effective cancer targeting. Natural macrophage membranes along with their associated membrane proteins were reconstructed into vesicles and then coated onto synthetic UCNPs...
October 8, 2016: Journal of Biomedical Materials Research. Part A
Stefania Biffi, Luca Petrizza, Chiara Garrovo, Enrico Rampazzo, Laura Andolfi, Pierangela Giustetto, Ivaylo Nikolov, Gabor Kurdi, Miltcho Boyanov Danailov, Giorgio Zauli, Paola Secchiero, Luca Prodi
PURPOSE: The aim of the present study was to develop nanoprobes with theranostic features, including - at the same time - photoacoustic, near-infrared (NIR) optical imaging, and photothermal properties, in a versatile and stable core-shell silica-polyethylene glycol (PEG) nanoparticle architecture. MATERIALS AND METHODS: We synthesized core-shell silica-PEG nanoparticles by a one-pot direct micelles approach. Fluorescence emission and photoacoustic and photothermal properties were obtained at the same time by appropriate doping with triethoxysilane-derivatized cyanine 5...
2016: International Journal of Nanomedicine
James Jenkins, Sergey M Borisov, Dmitri B Papkovsky, Ruslan I Dmitriev
Live cells function within narrow limits of physiological temperature (T), O2 and metabolite concentrations. We have designed a cell-permeable T-sensitive fluorescence lifetime-based nanoprobe based on lipophilic sulforhodamine, which stains 2D and 3D cell models, shows cytoplasmic localization and robust response to T (~0.037 ns/K). Subsequently, we evaluated the probe and FLIM technique for combined imaging of T and O2 gradients in metabolically active cells. We found that in adherent 2D culture of HCT116 cells intracellular T and O2 are close to ambient values...
October 4, 2016: Analytical Chemistry
Zhihua Li, Haixia Miao, Ying Fu, Yuxiang Liu, Ran Zhang, Bo Tang
A novel method of fabricating water-soluble bio-probes with ultra-small size such as NaYF4:Yb,Er (18 nm), NaGdF4:Yb,Er (8 nm), CaF2:Yb,Er (10 nm), PbS (7 nm), and ZnS (12 nm) has been developed to provide for the solubility switch of nanoparticles from oil-soluble to water-soluble in terms of hydrion rivalry aided by ultrasonic. Using NaYF4:Yb,Er (18 nm) as an example, we evaluate the properties of as-prepared water-soluble nanoparticles (NPs) by using thermogravimetric analyses (TGA), Fourier transform infrared spectroscopy (FTIR), zeta potential (ζ) testing, and 1H nuclear magnetic resonance ((1)HNMR)...
December 2016: Nanoscale Research Letters
Kishor Karki, James R Ewing, Meser M Ali
In brain tumors, delivering nanoparticles across the blood-tumor barrier presents major hurdles. A clinically relevant MRI contrast agent, GdDOTA and a near-infrared (NIR) fluorescent dye, DL680 were conjugated to a G5 PAMAM dendrimer, thus producing a dual-mode MRI and NIR imaging agent. Systemic delivery of the subsequent nano-sized agent demonstrated glioma-specific accumulation, probably due to the enhanced permeability and retention effect. In vivo MRI detected the agent in glioma tissue, but not in normal contralateral tissue; this observation was validated with in vivo and ex vivo fluorescence imaging...
August 2016: Journal of Nanomedicine & Nanotechnology
Hui Wang, Songjin Zhang, Xiumei Tian, Chufeng Liu, Lei Zhang, Wenyong Hu, Yuanzhi Shao, Li Li
Nanoprobes for combined optical and magnetic resonance imaging have tremendous potential in early cancer diagnosis. Gold nanoparticles (AuNPs) co-doped with Gd2O3 mesoporous silica nanocomposite (Au/Gd@MCM-41) can produce pronounced contrast enhancement for T1 weighted image in magnetic resonance imaging (MRI). Here, we show the remarkably high sensitivity of Au/Gd@MCM-41 to the human poorly differentiated nasopharyngeal carcinoma (NPC) cell line (CNE-2) using fluorescence lifetime imaging (FLIM). The upconversion luminescences from CNE-2 and the normal nasopharyngeal (NP) cells (NP69) after uptake of Au/Gd@MCM-41 show the characteristic of two-photon-induced-radiative recombination of the AuNPs...
October 3, 2016: Scientific Reports
Haojun Jin, Yuqian Liu, Tianshu Xu, Xiaojun Qu, Feika Bian, Qingjiang Sun
By complexing a non-ionic G-quadruplex ligand with hybrid dual-emission quantum dots (QDs), a ratiometric fluorescent nanoprobe is developed for G-quadruplex detection in a sensitive and specific manner. The QDs nanohybrid comprised of a green-emission QD (gQD) and multiple red-emission QDs (rQDs) inside and outside of a silica shell, respectively, is utilized as the signal displaying unit. Only the presence of G-quadruplex can displace the ligand from QDs, breaking up the QDs-ligand complexation, and inducing the restoration of the rQDs fluorescence...
October 1, 2016: Analytical Chemistry
Jun Xu, Xiaoke Shen, Lei Jia, Mingming Zhang, Tao Zhou, Yukun Wei
Since bacterial spores, such as Bacillus anthracis spores, are extremely hazardous to human beings and animals, efforts have focused on the development of bacterial spore detector with rapid response and high selectivity and sensitivity. Therefore, we reported a facile one-step chelating-reagent-assisted hydrothermal synthesis of lanthanide-doped fluorapatite (FA) nanoprobes for detecting the biomarker of bacterial spores. In FA synthesis, ethylenediaminetetraacetic acid (EDTA) can serve not only as a shape controller and a stabilizer but also as a chelating reagent for lanthanide ions...
September 21, 2016: Biosensors & Bioelectronics
Ning Huang, Si Cheng, Xiang Zhang, Qi Tian, Jiangli Pi, Jun Tang, Qin Huang, Feng Wang, Jin Chen, Zongyi Xie, Zhongye Xu, Weifu Chen, Huzhi Zheng, Yuan Cheng
Delivery of imaging agents to brain glioma is challenging because the blood-brain barrier(BBB) functions as a physiological checkpoint guarding the central nervous system from circulating large molecules. Moreover, the ability of existing probes to target glioma has been insufficient and needs to be improved. In present study, PEG-based long circulation, CdSe/ZnS quantum dots(QDs)-based nanoscale and fluorescence, asparagines-glycine-arginine peptides(NGR)-based specific CD13 recognition were integrated to design and synthesize a novel nanoprobe by conjugating biotinylated NGR peptides to avidin-PEG-coated QDs...
September 25, 2016: Nanomedicine: Nanotechnology, Biology, and Medicine
Xin-Chun Huang, Yuko Inoue-Aono, Yuji Moriyasu, Pei-Ying Hsieh, Wei-Ming Tu, Shae-Chien Hsiao, Wan-Neng Jane, Hsin-Yun Hsu
Autophagy is a self-protection process against reactive oxygen species (ROS). The intracellular level of ROS increased when cells were cultured under nutrient starvation. Antioxidants such as glutathione and ascorbic acid play an important role in ROS removal. However, the cellular redox state in the autophagic pathway is still unclear. Herein, we developed a new redox-sensitive probe with a disulfide-linked silica scaffold to enable the sensing of the reduction environment in cell organelles. This redox-responsive silica nanoprobe (ReSiN) could penetrate the plant cell wall and release fluorescent molecules in response to redox states...
October 6, 2016: Analytical Chemistry
Jun Zhou, Hong Weng, Yihui Huang, Yueqing Gu, Liping Tang, Wenjing Hu
Release of reactive oxygen species (ROS) accompanied with acute inflammation and infection often results in cell death and tissue injury. Several ROS-reactive bioluminescent probes have been investigated in recent years to detect ROS activity in vivo. Unfortunately, these probes cannot be used to quantify the degree of ROS activity and inflammatory responses due to the fact that the extent of the bioluminescent signals is also probe-concentration dependent. To address this challenge, we fabricated a ratiometric ROS probe in which both ROS-sensitive chemiluminescent agents and ROS-insensitive fluorescent reference dye were conjugated to particle carriers...
August 2016: Journal of Biomedical Nanotechnology
Satbir Singh, Pawan Kumar, Benny Abraham Kaipparettu, Bipin Kumar Gupta
Herein, we introduce a novel strategy for the synthesis of Eu(3+) doped α-sodium gadolinium fluoride (α-NaGd0.88F4:Eu0.12 (3+)) based luminomagnetic nanophosphors using hydrothermal route. The synthesized nanophosphor has exceptional luminescent and paramagnetic properties in a single host lattice, which is highly desirable for biomedical applications. This highly luminescent nanophosphor with an average particle size ∼ 5±3 nm enables high-contrast fluorescent imaging with decreased light scattering. In vitro cellular uptake is shown by fluorescent microscopy that envisages the characteristic hypersensitive red emission of Eu(3+) doped α-sodium gadolinium fluoride centered at 608 nm ((5)D0-(7)F2) upon 465 nm excitation wavelength...
2016: RSC Advances
Hanchun Yao, Li Su, Man Zeng, Li Cao, Weiwei Zhao, Chengqun Chen, Bin Du, Jie Zhou
Carbon dots (CDs) are one of the most highlighted carbon-based materials for biological applications, such as optical imaging nanoprobes, which are used for labeling cells in cancer treatment mainly due to their biocompatibility and unique optical properties. In this study, gadolinium (Gd)-complex-containing CDs were obtained through a one-step microwave method to develop multimodal nanoprobes integrating the advantages of optical and magnetic imaging. The obtained Gd-CDs exhibited highly fluorescent properties with excellent water solubility and biological compatibility...
2016: International Journal of Nanomedicine
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