Read by QxMD icon Read


Jianlei Shen, Qian Tang, Li Li, Jiang Li, Xiaolei Zuo, Xiangmeng Qu, Hao Pei, Lihua Wang, Chunhai Fan
Precise control over quantum dots (QDs) valency is critical and fundamental for quantitative imaging in living cells. However, prior approaches on valence control of QDs remain restricted to single types of valences. Here we report a DNA-programmed general strategy for valence engineering of QDs with high modularity and high yield. By employing a series of programmable DNA scaffolds, we generated QDs with tunable valences in a single step with near-quantitative yield (> 95%). We further demonstrated the use of these valence-engineered QDs to develop 12 types of topologically organized QDs-QDs and QDs-AuNPs and 4 types of fluorescent resonance energy transfer (FRET) nanostructures...
October 23, 2017: Angewandte Chemie
Tiffany C Kwong, Farouk Nouizi, Jaedu Cho, Yuting Lin, Uma Sampathkumaran, Gultekin Gulsen
Previously, we demonstrated that temperature-modulated fluorescence tomography (TM-FT) could provide fluorescence images with high quantitative accuracy and the spatial resolution of focused ultrasound. TM-FT is based on scanning the focused ultrasound across the medium to activate temperature-reversible fluorescent nanoprobes (ThermoDots). This technique can resolve small fluorescent targets located several centimeters deep in turbid media with millimeter resolution. Our past studies with this multimodality technique used agar phantoms, which could not represent the true heterogeneous nature of the acoustic and optical properties of biological tissue...
October 1, 2017: Applied Optics
Stefania Lettieri, Marta d'Amora, Adalberto Camisasca, Alberto Diaspro, Silvia Giordani
Multishell fullerenes, known as carbon nano-onions (CNOs), have emerged as a platform for bioimaging because of their cell-penetration properties and minimal systemic toxicity. Here, we describe the covalent functionalization of CNOs with a π-extended distyryl-substituted boron dipyrromethene (BODIPY) dye with on/off modulated fluorescence emission activated by an acidic environment. The switching properties are linked to the photoinduced electron transfer (PET) characteristics of the dimethylamino functionalities attached to the BODIPY core...
2017: Beilstein Journal of Nanotechnology
Xiaoying Xu, Lingzhou Zhao, Xin Li, Peng Wang, Jinhua Zhao, Xiangyang Shi, Mingwu Shen
Multifunctional low-generation dendrimer-entrapped gold nanoparticles (Au DENPs) were designed and synthesized. The formed Au DENPs modified with an arginine-glycine-aspartic peptide and labeled with (99m)Tc possess a uniform size distribution, desirable colloidal stability and biocompatibility, and can be used as a promising nanoprobe for targeted SPECT/CT imaging of αvβ3 integrin-expressing tumors.
October 17, 2017: Biomaterials Science
Edouard Alphandéry, Darine Abi Haidar, Olivier Seksek, Maxime Thoreau, Alain Trautmann, Nadege Bercovici, Florence Gazeau, François Guyot, Imène Chebbi
We report a method of fabrication of fluorescent magnetosomes, designated as MCR400, in which 400 μM of rhodamine B are introduced in the growth medium of AMB-1 magnetotactic bacteria and fluorescent magnetosomes are then extracted from these bacteria. These fluorescent magnetosomes behave differently from most fluorescent nanoprobes, which often lead to fluorescence losses over time due to photobleaching. Indeed, when MCR400 are heated to 30-90 °C, brought to an acidic pH, or exposed to radiations, we observed that their fluorescence intensity increased...
October 16, 2017: ACS Applied Materials & Interfaces
Daiyuan Tang, Wei Gao, Yajiang Yuan, Lingling Guo, Xifan Mei
Nanoprobes are rapidly becoming potentially transformative tools on disease diagnostics for a wide range of in vivo computed tomography (CT) imaging. Compared with conventional molecular-scale contrast agents, nanoparticles (NPs) promise improved abilities for in vivo detection. In this study, novel polyethylene glycol (PEG)-functionalized Au nanoparticles with star shape (AuNS@PEG) with strong X-ray mass absorption coefficient were synthesized as CT imaging contrast agents. Experimental results revealed that AuNS@PEG nanoparticles are well constructed with ultrasmall sizes, effective metabolisability, high computed tomography value, and outstanding biocompatibility...
October 12, 2017: Nanoscale Research Letters
Guobin Mao, Qin Cai, Fubing Wang, Changliang Luo, Xinghu Ji, Zhike He
As the blood glucose concentration is an important clinical parameter of diabetes, the rapid and effective detection of blood glucose is very significant for monitoring and managing the diabetes. Here, a facile method to prepare Rox-DNA functionalized CdZnTeS quantum dots (QDs) was developed. The Rox-DNA functionalized CdZnTeS QDs were prepared by one-pot hydrothermal method through phosphoro- -thioate DNA bounded to QDs, which employed as a ratiometric fluorescent probe for the rapid and sensitive detection of H2O2 and glucose...
October 11, 2017: Analytical Chemistry
Mustafa Salih Hizir, Neil M Robertson, Mustafa Balcioglu, Esma Alp, Muhit Rana, Mehmet V Yigit
A typical lock-and-key sensing strategy, relying only on the most dominant interactions between the probe and target, could be too limiting. In reality, the information received upon sensing is much richer. Non-specific events due to various intermolecular forces contribute to the overall received information with different degrees, and when analyzed, could provide a much more powerful detection opportunity. Here, we have assembled a highly selective universal sensor array using water-soluble two-dimensional nanoparticles (nGO, MoS2 and WS2) and fluorescent DNA molecules...
August 1, 2017: Chemical Science
Xiaoxiao Shi, Meili Hou, Shuang Bai, Xiaoqian Ma, Yong-E Gao, Bo Xiao, Peng Xue, Yuejun Kang, Zhigang Xu, Chang Ming Li
Stimuli-responsive nanomedicine with theranostic functionalities while reduced side-effects has attracted growing attention, although there are some major obstacles to overcome before clinical applications. Herein, we present an acid-activatable theranostic unimolecular micelles based on amphiphilic star-like polymeric prodrug to systematically address typical existing issues. This smart polymeric prodrug has a preferable size of about 35 nm and strong micellar stability in aqueous solution, which is beneficial to long-term blood circulation and efficient extravasation from tumoral vessels...
October 5, 2017: Molecular Pharmaceutics
Danting Cui, Xiaodan Lu, Chenggong Yan, Xiang Liu, Meirong Hou, Qi Xia, Yikai Xu, Ruiyuan Liu
Bombesin (BBN), an analog of gastrin-releasing peptide (GRP), specifically binds to GRP receptors, which are overexpressed in human prostate cancer (PC). Here, we synthesized a BBN-modified gadolinium oxide (Gd2O3) nanoprobe containing fluorescein (Gd2O3-5(6)-carboxyfluorescein [FI]-polyethylene glycol [PEG]-BBN) for targeted magnetic resonance (MR)/optical dual-modality imaging of PC. The Gd2O3-FI-PEG-BBN nanoparticles exhibited a relatively uniform particle size with an average diameter of 52.3 nm and spherical morphology as depicted by transmission electron microscopy...
2017: International Journal of Nanomedicine
Yan Chen, Quan Zhou, Xue Li, Fa Wang, Kevin Heist, Rork D Kuick, Scott Owens, Thomas Wang
Hepatocellular carcinoma (HCC) is a common worldwide cancer that is rising rapidly in incidence. MRI is a powerful non-invasive imaging modality for HCC detection but lack of specific contrast agents limits visualization of small tumors. EGFR is frequently overexpressed in HCC and is a promising target. Peptides have fast binding kinetics, short circulatory half-life, low imaging background, high vascular permeability, and enhanced tissue diffusion for deep tumor penetration. We demonstrate a peptide specific for EGFR labeled with an ultra-small paramagnetic iron oxide (UPIO) nanoparticle with 3...
October 3, 2017: Bioconjugate Chemistry
Jiajia Huang, Haodong Liu, Naixie Zhou, Ke An, Ying Shirley Meng, Jian Luo
Spontaneous and anisotropic surface segregation of W cations in LiMn1.5Ni0.5O4 particles can alter the Wulff shape and improve surface stability, thereby significantly improving the electrochemical performance. An Auger electron nanoprobe was employed to identify the anisotropic surface segregation, whereby W cations prefer to segregate to {110} surface facets to decrease its relative surface energy according to Gibbs adsorption theory and subsequently increase its surface area according to Wulff theory. Consequently, the rate performance is improved (e...
October 16, 2017: ACS Applied Materials & Interfaces
Yuan Wan, Gong Cheng, Xin Liu, Si-Jie Hao, Merisa Nisic, Chuan-Dong Zhu, Yi-Qiu Xia, Wen-Qing Li, Zhi-Gang Wang, Wen-Long Zhang, Shawn J Rice, Aswathy Sebastian, Istvan Albert, Chandra P Belani, Si-Yang Zheng
Extracellular vesicles (EVs) can mediate intercellular communication by transferring cargo proteins and nucleic acids between cells. The pathophysiological roles and clinical value of EVs are under intense investigation, yet most studies are limited by technical challenges in the isolation of nanoscale EVs (nEVs). Here, we report a lipid nanoprobe that enables spontaneous labelling and magnetic enrichment of nEVs in 15 minutes, with isolation efficiency and cargo composition similar to what can be achieved by the much slower and bulkier method of ultracentrifugation...
2017: Nature biomedical engineering
Dong Zhu, Zhao Yi Miao, Yue Hu, Xiao Jing Zhang
A single-step, homogeneous and sensitive LRET assay is presented for the detection of miRNAs. The amplification-free assay provides a unique combination of high specificity with dual-recognition approach of different hybridization and ligation steps and preventing background auto-fluorescence in biological samples using upconversion nanoparticles (UCNPs) as signal-producing nanoprobes. The assay probe is composed of signal-producing unit (a pair of homogeneous upconversion luminescence resonance energy transfer (UC-LRET)-based oligonucleotides) and recognition unit (two adaptor oligonucleotides)...
September 22, 2017: Biosensors & Bioelectronics
Yanqi Luo, Parisa Khoram, Sarah Brittman, Zhuoying Zhu, Barry Lai, Shyue Ping Ong, Erik C Garnett, David P Fenning
Optoelectronic devices based on hybrid perovskites have demonstrated outstanding performance within a few years of intense study. However, commercialization of these devices requires barriers to their development to be overcome, such as their chemical instability under operating conditions. To investigate this instability and its consequences, the electric field applied to single crystals of methylammonium lead bromide (CH3 NH3 PbBr3 ) is varied, and changes are mapped in both their elemental composition and photoluminescence...
September 29, 2017: Advanced Materials
Nicola J Rogers, Hannah C Jeffery, Sunil Claire, David J Lewis, Gerald Zikeli, Nikolas J Hodges, Stuart Egginton, Gerard B Nash, Zoe Pikramenou
AIM: Imaging of blood flow in narrow channels and close to vessel walls is important in cardiovascular research for understanding pathogenesis. Our aim was to provide novel nanoprobes with visible emission and long lifetimes as trackers of flow. MATERIALS & METHODS: Gold nanoparticles coated with an iridium complex were prepared. Luminescence imaging was used to monitor their flows in different hematocrit blood and in murine tissues. RESULTS: The velocities are independent of hematocrit level and the nanoparticles entering blood circulation can be clearly detected in vessels in lungs, mesentery and the skeletal muscle...
September 29, 2017: Nanomedicine
Ben Shi, Xianfeng Gu, Zhijun Wang, Ge Xu, Qiang Fei, Jie Tang, Chunchang Zhao
Probes bearing good aqueous solubility and biocompatibility as well as fast response can serve as ideal tools for evaluating the underlying molecular mechanism of endogenous production of H2S caused by drugs; however, they are still lacking but highly desirable. Here, we demonstrate a novel strategy for constructing highly efficient H2S nanoprobes through locking Förster resonance energy transfer borondipyrromethene (BODIPY) pairs in water-dispersible core-shell silica nanoparticles. Importantly, these nanocomposites can effectively confine complementary guests within the same cores due to the existence of a shield, thus guaranteeing efficient Förster resonance energy transfer...
October 18, 2017: ACS Applied Materials & Interfaces
Yu Qian, Xing Xing, Ya Xu, Zhenda Lu, Weihua Zhang
We report a simple yet robust method for fabricating single perovskite quantum dot decorated fiber nanotips. In this method, a single quantum dot is directly picked up and subsequently glued on the apex of a specially fabricated cantilever fiber tip with a high success rate (approx. 70%) without using expensive close-loop feedback systems. Thanks to the flexibility and robustness of the fiber tips, no damage of the tips was observed in the process. Moreover, nanocrystal dispersing technique was developed to avoid undesired aggregations of quantum dots, and it guarantees that only one quantum dot is glued for each time...
September 25, 2017: Nanotechnology
Chunxiang Li, Weisen Lu, Ming Zhu, Bo Tang
The performance of the photoelectrochemical (PEC) bioanalysis relies closely on the properties of the used photoactive species. In this study, a visible-light induced PEC active species, [(C6)2Ir(dcbpy)](+)PF6(-) (C6 = coumarin 6, dcbpy = 2,2'-bipyridine-4,4'-dicarboxylic acid) was prepared based on C6 with the stronger absorbance in the visible region. The as-prepared complex was characterized by (1)H NMR, UV-visible absorption and cyclic voltammetry. It exhibits intense absorption in visible region at 480 nm with a molar extinction coefficient (ε) of more 40000 M(-1) cm(-1), which is approximately twice that of Ru(bpy)3(2+)...
October 17, 2017: Analytical Chemistry
Guangxue Feng, Jie Liu, Rongrong Liu, Duo Mao, Nikodem Tomczak, Bin Liu
Fluorescent and biocompatible organic nanoparticles have attracted great interest in cancer detection and imaging, but the nonspecific cellular uptake has limited the detection specificity and sensitivity. Herein, the authors report the ultrasmall conjugated polymer nanoparticles (CPNs) with bright far-red/near-infrared emission for targeted cancer imaging with high specificity. The sizes of the ultrasmall CPNs are around 6 nm (CPN6), while large CPNs show sizes around 30 nm (CPN30). Moreover, CPN6 exhibits largely improved fluorescence quantum yield (η) of 41% than CPN30 (25%)...
September 2017: Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"