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https://read.qxmd.com/read/30761616/nir-biosensing-of-neurotransmitters-in-stem-cell-derived-neural-interface-using-advanced-core-shell-upconversion-nanoparticles
#1
Hudifah Rabie, Yixiao Zhang, Nicholas Pasquale, Maureen J Lagos, Philip E Batson, Ki-Bum Lee
Nondestructive neurotransmitter detection and real-time monitoring of stem cell differentiation are both of great significance in the field of neurodegenerative disease and regenerative medicine. Although luminescent biosensing nanoprobes have been developed to address this need, they have intrinsic limitations such as autofluorescence, scattering, and phototoxicity. Upconversion nanoparticles (UCNPs) have gained increasing attention for various biomedical applications due to their high photostability, low auto-fluorescent background, and deep tissue penetration; however, UCNPs also suffer from low emission intensities due to undesirable energy migration pathways...
February 13, 2019: Advanced Materials
https://read.qxmd.com/read/30742148/a-nd-3-sensitized-upconversion-nanosystem-with-dual-photosensitizers-for-improving-photodynamic-therapy-efficacy
#2
Man Yang, Han Wang, Zhaohui Wang, Zhihao Han, Yueqing Gu
The efficacy of photodynamic therapy (PDT) was greatly hindered by the use of a 980 nm laser with undesired overheating effects as well as low reactive oxygen species (ROS) yields. Herein, we address these problems using a dual-photosensitizer (PS) loaded upconversion nanoparticle (UCNP) system. In detail, the NaYF4:Yb/Er/Nd@NaYF4:Nd core-shell UCNP system was designed to exhibit 808 nm laser excitation ability to avoid unfavorable thermal effects. More importantly, the co-encapsulation of dual PS, in terms of merocyanine 540 (MC540) and zinc phthalocyanine (ZnPc), could be respectively triggered by the dual emissions of UCNPs, which could generate sufficient ROS with improved efficiency...
February 11, 2019: Biomaterials Science
https://read.qxmd.com/read/30712105/upconversion-fluorescent-aptasensor-for-bisphenol-a-and-17%C3%AE-estradiol-based-on-a-nanohybrid-composed-of-black-phosphorus-and-gold-and-making-use-of-signal-amplification-via-dna-tetrahedrons
#3
Shuyue Ren, Qiaofeng Li, Ye Li, Shuang Li, Tie Han, Jiang Wang, Yuan Peng, Jialei Bai, Baoan Ning, Zhixian Gao
This study describes an upconversion fluorescent aptasensor based on black phosphorus nanohybrids and self-assembled DNA tetrahedrons dual-amplification strategy for rapid detection of the environmental estrogens bisphenol A (BPA) and 17β-estradiol (E2). Tetrahedron complementary DNAs (T-cDNAs) were self-assembled in an oriented fashion on a 2D nanohybrid composed of black phosphorus (BP) and gold to give a materials of architecture BP-Au@T-cDNAs. In parallel, core-shell upconversion nanoparticles were modified with aptamers (UCNPs@apts) and used as capture probes...
February 2, 2019: Mikrochimica Acta
https://read.qxmd.com/read/30695767/upconversion-nanoparticles-for-i-in-vivo-i-applications-limitations-and-future-perspectives
#4
Blanca Del Rosal, Daniel Jaque Garcia
UCNPs have attracted a great deal of attention as near infrared-excited luminescent probes for biomedical applications. UCNPs can provide contrast for in vivo imaging, act as luminescent temperature reporters and excite different molecules to trigger therapeutic processes. While the unique features of UCNPs are well-suited for certain applications, their intrinsic limitations may prevent their general use in preclinical and clinical settings as luminescent probes. In this work, we analyze the role of UCNPs in research in small animal models...
January 29, 2019: Methods and Applications in Fluorescence
https://read.qxmd.com/read/30690440/colour-optimized-quantum-yields-of-yb-tm-co-doped-upconversion-nanocrystals
#5
Marco Kraft, Christian Wuerth, Emilia Palo, Tero Soukka, Ute Resch-Genger
We present here a systematic analysis of the influence of Tm<sup>3+</sup> doping concentrations (<i>x<sub>Tm</sub></i>) on the excitation power (<i>P</i>)-dependent upconversion luminescence and -performance of hexagonal-phase NaYF<sub>4</sub>: 20 % Yb<sup>3+</sup>, <i>x<sub>Tm</sub></i> % Tm<sup>3+</sup> upconversion nanoparticles (UCNPs) for <i>x<sub>Tm</sub></i> of 0...
January 28, 2019: Methods and Applications in Fluorescence
https://read.qxmd.com/read/30688444/optically-active-upconverting-nanoparticles-with-induced-circularly-polarized-luminescence-and-enantioselectively-triggered-photopolymerization
#6
Xue Jin, Yutao Sang, Yonghong Shi, Yuangang Li, Xuefeng Zhu, Pengfei Duan, Minghua Liu
In this work, lanthanide-doped upconversion nanoparticles (UCNPs) showing upconverted circularly polarized luminescence were demonstrated in an organic-inorganic co-assembled system. Achiral UCNPs (NaYF4 :Yb/Er or NaYF4 :Yb/Tm) can be encapsulated into chiral helical nanotubes through the procedure of co-gelation. These co-gel systems display intense upconverted circularly polarized luminescence (UC-CPL) ranging from ultraviolet (UV, 300 nm) to near-infrared (NIR, 850 nm) wavelength. In addition, the UV part of UC-CPL can be used to initiate the enantioselective polymerization of diacetylene...
January 28, 2019: ACS Nano
https://read.qxmd.com/read/30687981/tunable-resonator-upconverted-emission-true-color-printing-and-applications-in-optical-security
#7
Hailong Liu, Jiahui Xu, Hao Wang, Yejing Liu, Qifeng Ruan, Yiming Wu, Xiaogang Liu, Joel K W Yang
Lanthanide-doped nanophosphors are promising in anti-counterfeiting and security printing applications. These nanophosphors can be incorporated as transparent inks that fluoresce by upconverting near-infrared illumination into visible light to allow easy verification of documents. However, these inks typically exhibit a single luminescent color, low emission efficiency, and low print resolutions. Tunable resonator-upconverted emission (TRUE) is achieved by placing upconversion nanoparticles (UCNPs) within plasmonic nanoresonators...
January 27, 2019: Advanced Materials
https://read.qxmd.com/read/30681836/an-upconversion-nanoparticle-enables-near-infrared-optogenetic-manipulation-of-the-c-elegans-motor-circuit
#8
Yanxiao Ao, Kanghua Zeng, Bin Yu, Yu Miao, Wesley Hung, Zhongzheng Yu, Yanhong Xue, Timothy Thatt Yang Tan, Tao Xu, Mei Zhen, Xiangliang Yang, Yan Zhang, Shangbang Gao
Near-infrared (NIR) light penetrates tissue deeply, but its application to motor behavior stimulation has been limited by the lack of known genetic NIR light-responsive sensors. We designed and synthesized a Yb3+/Er3+/Ca2+-based lanthanide-doped upconversion nanoparticle (UCNP) that effectively converts 808 nm NIR light to green light emission. This UCNP is compatible with Chrimson, a cation channel activated by green light; as such, it can be used in the optogenetic manipulation of the motor behaviors of C...
January 25, 2019: ACS Nano
https://read.qxmd.com/read/30678969/multifunctional-nanoclusters-of-nayf-4-yb-3-er-3-upconversion-nanoparticle-and-gold-nanorod-for-simultaneous-imaging-and-targeted-chemotherapy-of-bladder-cancer
#9
Suehyun K Cho, Lih-Jen Su, Chenchen Mao, Connor D Wolenski, Thomas W Flaig, Wounjhang Park
This paper reports successful synthesis of multifunctional nanoclusters of upconversion nanoparticle (UCNP) and gold nanorod (AuNR) through a PEGylation process. UCNPs emit visible luminescence under near-infrared excitation, producing high-contrast images with no background fluorescence. When coupled with AuNRs, the resulting UCNP-AuNR multifunctional nanoclusters are capable of simultaneous detection and treatment of bladder cancer. These UCNP-AuNR nanoclusters are further functionalized with antibodies to epidermal growth factor receptor (EGFR) to target bladder cancer cells known to overexpress EGFRs...
April 2019: Materials Science & Engineering. C, Materials for Biological Applications
https://read.qxmd.com/read/30673225/fret-based-upconversion-nanoprobe-sensitized-by-nd3-for-the-ratiometric-detection-of-hydrogen-peroxide-in-vivo
#10
Han Wang, Yongkuan Li, Man Yang, Peng Wang, Yueqing Gu
The exorbitant level of hydrogen peroxide is closely related to many human diseases. The development of novel probes for H2O2 detection will be beneficial to disease diagnosis. In this study, a novel Nd3+-sensitized upconversion nanoprobe based on FRET (Förster Resonance Energy Transfer) was firstly developed for sensing H2O2. This nanosystem was made of core-shell upconversion nanoparticles (emission at 540 nm and 660 nm), DCM (dicyanomethylene-4H-pyran)-H2O2 and PAA-octylamine. Obviously, UCNPs doped with Nd3+ acted as an energy donor, and DCM-H2O2, transferring to DCM-OH with the reaction of H2O2, acted as an energy acceptor...
January 23, 2019: ACS Applied Materials & Interfaces
https://read.qxmd.com/read/30667127/circular-polarized-light-activated-chiral-satellite-nanoprobes-for-the-imaging-and-analysis-of-multiple-metal-ions-in-living-cells
#11
Chuanlai Xu, Rui Gao, Liguang Xu, Changlong Hao, Hua Kuang
Here, we constructed a handedness-dependent circular polarized light (CPL)-activated chiral satellite assembly formed by DNAzyme-driven spiny nanorod dimer and upconversion nanoparticles (UCNPs), enabling the simultaneous quantitative analysis of multiple divalent metal ions, namely, copper (Cu2+), magnesium (Mg2+) and zinc (Zn2+) ions, in living cells. These chiral nanoprobes, with intense triple luminescence signals at 542 nm, 580 nm and 680 nm, in coordination with their corresponding divalent metal ions under 980 nm left circular polarized (LCP) light illumination, were used as an in situ confocal bio-imaging platform for the quantitation of the given intracellular metal ions...
January 22, 2019: Angewandte Chemie
https://read.qxmd.com/read/30662565/near-infrared-light-regulated-cancer-theranostic-nanoplatform-based-on-aggregation-induced-emission-luminogen-encapsulated-upconversion-nanoparticles
#12
Guorui Jin, Rongyan He, Qian Liu, Min Lin, Yuqing Dong, Kai Li, Ben Zhong Tang, Bin Liu, Feng Xu
Photodynamic therapy (PDT) has been widely applied in the clinic for the treatment of various types of cancer due to its precise controllability, minimally invasive approach and high spatiotemporal accuracy as compared with conventional chemotherapy. However, the porphyrin-based photosensitizers (PSs) used in clinics generally suffer from aggregation-caused reductions in the generation of reactive oxygen species (ROS) and limited tissue penetration because of visible light activation, which greatly hampers their applications for the treatment of deep-seated tumors...
2019: Theranostics
https://read.qxmd.com/read/30661613/molecular-structure-regulation-and-enzyme-cascade-signal-amplification-strategy-for-upconversion-ratiometric-luminescent-and-colorimetric-alkaline-phosphatase-detection
#13
Hongyu Chen, Zile Zhou, Qiujun Lu, Cuiyan Wu, Meiling Liu, Youyu Zhang, Shouzhuo Yao
Herein, molecular structure regulation and enzyme cascade signals amplification (MRECAmp) strategy was proposed to construct a novel upconversion ratiometric fluorescence and colorimetric dual-readout assay platform for highly sensitive and selective detection of alkaline phosphatase (ALP) activity. The detection strategy is divided into three aspects. Firstly, Ag+ oxidates o-phenylenediamine (OPD) to 2,3-diaminophennazine (OPDox), which can significantly quench upconversion fluorescence at 487 nm based on inner filter effects (IFE) while the upconversion emission at 668 nm was essentially unchanged for Zn2+ -doped NaYF4 :Yb3+ ,Er3+ ,Tm3+ upconversion nanoparticles (UCNPs) probes under the near-infrared (NIR) irradiation...
March 21, 2019: Analytica Chimica Acta
https://read.qxmd.com/read/30658229/electrochemiluminescence-sensor-based-on-upconversion-nanoparticles-and-oligoaniline-crosslinked-gold-nanoparticles-imprinting-recognition-sites-for-the-determination-of-dopamine
#14
Ying Gu, Junping Wang, Haipeng Shi, Mingfei Pan, Bing Liu, Guozhen Fang, Shuo Wang
For the determination of dopamine (DA) in serum samples, a quenching-type electrochemiluminescence sensor (MIECLS) was constructed in this study. Upconversion nanoparticles (UCNPs) enhanced by covalent organic frameworks (COFs)-based hybrid and oligoaniline-crosslinked gold nanoparticles (AuNPs) imprinting recognition sites were introduced in electrochemiluminescence (ECL) system at the first time. The porous COFs-based hybrid with large specific surface area was modified on the electrode firstly to hold more UCNPs and imprinting recognition sites...
December 27, 2018: Biosensors & Bioelectronics
https://read.qxmd.com/read/30641489/sensitization-of-upconverting-nanoparticles-with-a-nir-emissive-cyanine-dye-using-a-micellar-encapsulation-approach
#15
Maysoon Saleh, Ihor Panas, Florian Frenzel, Christian Wuerth, Bastian Rühle, Yuri L Slominskii, Alexander Demchenko, Ute Resch-Genger
Photon upconversion nanomaterials have a wide range of applications, including biosensing and deep-tissue imaging. Their typically very weak and narrow absorption bands together with their size dependent luminescence efficiency can limit their application potential. This has been addressed by increasingly sophisticated core-shell particle architectures including the sensitization with organic dyes that strongly absorb in the near infrared (NIR). In this work, we present a simple water-dispersible micellar system that features energy transfer from the novel NIR excitable dye, 1859 SL with a high molar absorption coefficient and a moderate fluorescence quantum yield to oleate-capped NaYF<sub>4</sub>:20%Yb(III),2%Er(III) upconversion nanoparticles (UCNP) upon 808 nm excitation...
January 14, 2019: Methods and Applications in Fluorescence
https://read.qxmd.com/read/30637510/white-light-emissive-upconversion-nanoparticles-for-visual-and-colorimetric-determination-of-the-pesticide-thiram
#16
Huaijing Sun, Qingsong Mei, Swati Shikha, Jinliang Liu, Jing Zhang, Yong Zhang
The authors describe the use of white-light emitting upconversion nanoparticles (WL-UCNPs) for visual detection of the pesticide thiram. The method is demonstrated to undergo a better discernable color change upon target binding. The WL-UCNPs are modified with the lead(II)-dithizone complex which acts as the energy acceptor and recognition unit. This leads to quenching of the blue (475 nm) and green (545 nm) emissions of the WL-UCNPs, while the red emission (650 nm) remains unaffected. Upon addition of thiram, the quenched emissions are recovered, with a linear signal increase in the range from 2 nM to 20 nM of thiram and a limit of detection of 0...
January 12, 2019: Mikrochimica Acta
https://read.qxmd.com/read/30637422/upconversion-enhancement-by-a-dual-resonance-all-dielectric-metasurface
#17
Chensheng Gong, Wen Liu, Nan He, Hongguang Dong, Yi Jin, Sailing He
Upconversion nanoparticles (UCNPs) have drawn much attention in the past decade due to their superior physicochemical features and great potential in biomedical and biophotonic studies. However, their low luminescence efficiency often limits their applications. Here, we demonstrated a dual-resonance all-dielectric metasurface to enhance the signals emitted by upconversion nanoparticles (NaYF4:Yb/Tm). An averaged upconversion signal enhancement of around 400 times is detected experimentally. The electric and magnetic dipole resonances of the metasurface are designed to enhance the local excitation field and the quantum efficiency of the upconversion nanoparticles, respectively...
January 14, 2019: Nanoscale
https://read.qxmd.com/read/30626081/energy-transfer-between-tm-doped-upconverting-nanoparticles-and-a-small-organic-dye-with-large-stokes-shift
#18
Anna López de Guereñu, Philipp Bastian, Pablo Wessig, Leonard John, Michael U Kumke
Lanthanide-doped upconverting nanoparticles (UCNP) are being extensively studied for bioapplications due to their unique photoluminescence properties and low toxicity. Interest in RET applications involving UCNP is also increasing, but due to factors such as large sizes, ion emission distributions within the particles, and complicated energy transfer processes within the UCNP, there are still many questions to be answered. In this study, four types of core and core-shell NaYF₄-based UCNP co-doped with Yb3+ and Tm3+ as sensitizer and activator, respectively, were investigated as donors for the Methyl 5-(8-decanoylbenzo[1,2-d:4,5-d']bis([1,3]dioxole)-4-yl)-5-oxopentanoate (DBD-6) dye...
January 8, 2019: Biosensors
https://read.qxmd.com/read/30625605/dopamine-functionalized-upconversion-nanoparticles-as-fluorescent-sensors-for-organophosphorus-pesticide-analysis
#19
Mengli Liu, Junyi Wei, Yao Wang, Hui Ouyang, Zhifeng Fu
Organophosphorus pesticide (OP) residues in agricultural products, herbal medicines and environment have attracted increasing concerns because they cause high healthy risk. Herein, a tyrosinase-mediated photoinduced electron transfer system was constructed for OPs analysis by using dopamine-functionalized upconversion nanoparticles (UCNPs) as fluorescent (FL) sensors. Dopamine quinone was produced by tyrosinase-mediated oxidation of dopamine on the surface of UCNPs, which acted as electron accepter to quench the FL emission of UCNPs...
April 1, 2019: Talanta
https://read.qxmd.com/read/30625551/an-ultrasensitive-homogeneous-aptasensor-for-carcinoembryonic-antigen-based-on-upconversion-fluorescence-resonance-energy-transfer
#20
Yujie Wang, Zikai Wei, Xianda Luo, Quan Wan, Rongliang Qiu, Shizhong Wang
Carcinoembryonic antigen (CEA) has been recognized as one of the most important tumor markers. Herein, we reported an ultrasensitive homogeneous aptasensor based on fluorescence resonance energy transfer (FRET) between upconversion nanoparticles (UCNPs) and graphene oxide (GO) for CEA detection. The CEA aptamer modified UCNPs can bind to the surface of GO through π-π stacking interaction, resulting in fluorescence quenching due to the energy transfer from UCNPs to GO. After the introduction of CEA, the CEA aptamer preferentially combined with CEA to form three-dimensional structure which made UCNPs-aptamer dissociate from the GO, blocking the energy transfer process...
April 1, 2019: Talanta
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