A new kind of rhodamine-based fluorescence turn-on probe for monitoring ATP in mitochondria

Liu, Yifan,Lee, Dayoung,Wu, Di,Swamy, K.M.K.,Yoon, Juyoung Elsevier 2018 Sensors and actuators. B Chemical Vol.265 No.-

<P><B>Abstract</B></P> <P>We have developed a new kind of colorimetric and fluorescence “turn-on” probe based on rhodamine derivatives for the detection of adenosine-5′-triphosphate (ATP) through hydrogen bond interactions. Upon the addition of 5 mM ATP, the probe 1 shows a 65-fold enhancement in fluorescence intensity and a color change from colorless to pink. The probe 2 also shows very obvious color and fluorescence change with the presence of ATP. The experimental results show that this kind of probe has high specificity towards ATP over other anions, metal ions, and other nucleoside polyphosphates, except ADP. The enhanced emission and naked eye changes are attributed to spirolactam ring-opening, which is pH independent (pH (4.0–7.4)). The more important finding from our results is that the electron withdrawing group in the chain decreases the binding ability to ATP. The live cell imaging experiments in Hela cells indicated that probe <B>2</B> has cell permeability, and mainly locates to mitochondria.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Three new rhodamine derivatives bearing thiourea group are synthesized and reported as chemosensors for ATP. </LI> <LI> Probe <B>1, 2</B> and <B>3</B> showed distinct colorimetric and fluorescence changes with ATP. </LI> <LI> Probe <B>2</B> was successfully applied to monitor ATP in mitochondria. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A bispyrene derivative as a selective fluorescent probe for RNA

Liu, Yifan,Jun, Eun Jin,Kim, Gyoungmi,Lee, Ae-Ree,Lee, Joon-Hwa,Yoon, Juyoung The Royal Society of Chemistry 2014 Chemical communications Vol.50 No.19

<P>A novel bispyrene compound was synthesized to selectively detect RNA through excimer emission “turn-on” in aqueous solution at physiological pH (7.4). The compound was used to successfully image RNA in HeLa cells.</P> <P>Graphic Abstract</P><P>A novel bispyrene compound was synthesized to selectively detect RNA through excimer emission “turn-on” at physiological pH. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3cc49430f'> </P>

Fluorescent and Colorimetric Chemosensors for Anions, Metal Ions, Reactive Oxygen Species, Biothiols, and Gases

Yifan Liu,Ying Hu,이송이,이다영,윤주영 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.10

Colorimetric and fluorescent chemosensors have been actively studied in recent years, and this article covers our contributions to colorimetric and fluorescent chemosensors in detecting anions, metal ions, reactive oxygen species (ROS), reactive nitrogen species (RNS), biothiols, and gases. The chemosensors discussed in this article are categorized according to their corresponding analytes, and the final part is devoted to polydiacetylene-based chemosensors. We hope that this article will be beneficial in the design of chemosensors for various important analytes.

Preparation and investigation of Dy³⁺-doped Ca₉LiGd_2/3(PO₄)₇ single-phase full-color phosphor

Liu, Shihua,Liu, Simei,Wang, Jingjing,Sun, Pengfei,Zhong, Yifan,Jeong, Jung Hyun,Deng, Bin,Yu, Ruijin Elsevier 2018 Materials research bulletin Vol.108 No.-

<P><B>Abstract</B></P> <P>Novel single-phased white-light-emitting Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:<I>x</I>Dy<SUP>3+</SUP> (<I>x</I> = 0.02, 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30) β-Ca<SUB>3</SUB>(PO<SUB>4</SUB>)<SUB>2</SUB>-type phosphate phosphors were synthesized. The phase structure, luminescence, and thermal stability of the phosphors were characterized by X-ray powder diffraction analysis, photoluminescence excitation and emission spectra, thermal quenching, and decay curves. XRD analysis confirmed the phase formation of Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:Dy<SUP>3+</SUP> materials. Under the excitation of 352 nm, the emission of the Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:0.20Dy<SUP>3+</SUP> sample centered at blue (488 nm) and yellow (580 nm), which corresponded to <SUP>4</SUP>F<SUB>9/2</SUB>–<SUP>6</SUP>H<SUB>15/2</SUB> transition and <SUP>4</SUP>F<SUB>9/2</SUB>–<SUP>6</SUP>H<SUB>13/2</SUB> transition. The optimum dopant concentration of Dy<SUP>3+</SUP> ions was around 20 mol%, and the critical transfer distance of Dy<SUP>3+</SUP> was calculated as 18 Å. The thermal-quenching temperature was above 500 K for Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:0.20Dy<SUP>3+</SUP>. The developed phosphor has a great potential as a single-component white-light-emitting phosphor for UV-light-emitting diodes.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel single-phased Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:<I>x</I>Dy<SUP>3+</SUP> phosphor was firstly synthesized. </LI> <LI> Its structure, luminescent properties are well studied and characterized. </LI> <LI> It was promising as a single-component white-light-emitting phosphor for w-LEDs. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Green synthesis of fluorescent carbon dots from carrot juice for in vitro cellular imaging

Yang Liu,Yanan Liu,Mira Park,Soo-Jin Park,Yifan Zhang,Md Rashedunnabi Akanda,Byung-Yong Park,Hak Yong Kim 한국탄소학회 2017 Carbon Letters Vol.21 No.-

We report the use of carrot, a new and inexpensive biomaterial source, for preparing high quality carbon dots (CDs) instead of semi-conductive quantum dots for bioimaging application. The as-derived CDs possessing down and up-conversion photoluminescence features were obtained from carrot juice by commonly used hydrothermal treatment. The corresponding physiochemical and optical properties were investigated by electron microscopy, fluorescent spectrometry, and other spectroscopic methods. The surfaces of obtained CDs were highly covered with hydroxyl groups and nitrogen groups without further modification. The quantum yield of as-obtained CDs was as high as 5.16%. The cell viability of HaCaT cells against a purified CD aqueous solution was higher than 85% even at higher concentration (700 μg mL−1) after 24 h incubation. Finally, CD cultured cells exhibited distinguished blue, green, and red colors, respectively, during in vitro imaging when excited by three wavelength lasers under a confocal microscope. Offering excellent optical properties, biocompatibility, low cytotoxicity, and good cellular imaging capability, the carrot juice derived CDs are a promising candidate for biomedical applications.

The effects of deletion of cellobiohydrolase genes on carbon source-dependent growth and enzymatic lignocellulose hydrolysis in Trichoderma reesei

Ren Meibin,Wang Yifan,Liu Guoxin,Zuo Bin,Zhang Yuancheng,Wang Yunhe,Liu Weifeng,Liu Xiangmei,Zhong Yaohua 한국미생물학회 2020 The journal of microbiology Vol.58 No.8

The saprophytic fungus Trichoderma reesei has long been used as a model to study microbial degradation of lignocellulosic biomass. The major cellulolytic enzymes of T. reesei are the cellobiohydrolases CBH1 and CBH2, which constitute more than 70% of total proteins secreted by the fungus. However, their physiological functions and effects on enzymatic hydrolysis of cellulose substrates are not sufficiently elucidated. Here, the cellobiohydrolase-encoding genes cbh1 and cbh2 were deleted, individually or combinatively, by using an auxotrophic marker-recycling technique in T. reesei. When cultured on media with different soluble carbon sources, all three deletion strains (Δcbh1, Δcbh2, and Δcbh1Δcbh2) exhibited no dramatic variation in morphological phenotypes, but their growth rates increased apparently when cultured on soluble cellulase-inducing carbon sources. In addition, Δcbh1 showed dramatically reduced growth and Δcbh1Δcbh2 could hardly grew on microcrystalline cellulose (MCC), whereas all strains grew equally on sodium carboxymethyl cellulose (CMC-Na), suggesting that the influence of the CBHs on growth was carbon source-dependent. Moreover, five representative cellulose substrates were used to analyse the influence of the absence of CBHs on saccharification efficiency. CBH1 deficiency significantly affected the enzymatic hydrolysis rates of various cellulose substrates, where acid pre-treated corn stover (PCS) was influenced the least. CBH2 deficiency reduced the hydrolysis of MCC, PCS, and acid pre-treated and delignified corncob but improved the hydrolysis ability of filter paper. These results demonstrate the specific contributions of CBHs to the hydrolysis of different types of biomass, which could facilitate the development of tailor-made strains with highly efficient hydrolysis enzymes for certain biomass types in the biofuel industry.

A new method of phenol degradation by microarc plasma electrolysis

Yifan Zhang,Xiaoyue Jin,Jiahao Yu,Guijun Liu,Ying Wang,Wenbin Xue 한국표면공학회 2017 한국표면공학회 학술발표회 초록집 Vol.2017 No.11

Novel Schemes to Optimize Sampling Rate for Compressed Sensing

YiFan Zhang,Xuan Fu,Qixun Zhang,Zhiyong Feng,Xiaomin Liu 한국통신학회 2015 Journal of communications and networks Vol.17 No.5

The fast and accurate spectrum sensing over an ultra- wide bandwidth is a big challenge for the radio environment cogni- tion. Considering sparse signal feature, two novel compressed sens- ing schemes are proposed, which can reduce compressed sampling rate in contrast to the traditional scheme. One algorithm is dynam- ically adjusting compression ratio based on modulation recogni- tion and identification of symbol rate, which can reduce compres- sion ratio. Furthermore, without priori information of the modu- lation and symbol rate, another improved algorithm is proposed with the application potential in practice, which does not need to reconstruct the signals. The improved algorithm is divided into two stages, which are the approaching stage and the monitoring stage. The overall sampling rate can be dramatically reduced with- out the performance deterioration of the spectrum detection com- pared to the conventional static compressed sampling rate algo- rithm. Numerous results show that the proposed compressed sens- ing technique can reduce sampling rate by 35%, with an acceptable detection probability over 0.9.

Intestinal Anti-Inflammatory Effects of Selenized Ulva pertusa Polysaccharides in a Dextran Sulfate Sodium-Induced Inflammatory Bowel Disease Model

Yifan Wang,Han Ye,Leke Qiao,Chunying Du,Zhengpeng Wei,Ting Wang,Jingfeng Wang,Ruizhi Liu,Peng Wang 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.3

The purpose of this study was to examine the alleviative effects of selenized polysaccharides from Ulva pertusa (ulvan-Se) on inflammatory bowel disease (IBD) in mice. The dextran sulfate sodium (DSS)-induced IBD mouse model was used to explore the protective effects of ulvan-Se on the intestinal mechanical and immune barrier. At doses less than 1208 mg/kg·bw ulvan-Se showed no significant damage to Institute of Cancer Research (ICR) mice in an acute toxicity test. The results showed that DSS destroyed the mechanical barrier, which includes epithelial cells, while ulvan-Se promoted mRNA expression of tight junction proteins (zonula occludens protein 1, occludin, and claudin-1) and inhibited the infiltration of white blood cells into the intestines. At 100 mg/kg·bw, ulvan-Se enhanced the antioxidant capacity of mice more effectively than the 50 mg/kg·bw ulvan-Se. Furthermore, ulvan-Se improved the intestinal immune barrier by increasing immunoglobulin A and immunoglobulin M, while regulating the levels of interleukin (IL)-1β, interferon-γ, and IL-4. Oral administration of ulvan-Se also suppressed tumor necrosis factor-α, IL-1β, IL-6, and cyclooxygenase-2 mRNA expression mediated by the nuclear factor kappa B pathway. Taken together, our findings reveal that ulvan-Se could be used as a potential alternative supplement for reducing intestinal inflammation in IBD.

A Rendezvous Node Selection and Routing Algorithm for Mobile Wireless Sensor Network

( Yifan Hu ),( Yi Zheng ),( Xiaoming Wu ),( Hailin Liu ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.10

Efficient rendezvous node selection and routing algorithm (RNSRA) for wireless sensor networks with mobile sink that visits rendezvous node to gather data from sensor nodes is proposed. In order to plan an optimal moving tour for mobile sink and avoid energy hole problem, we develop the RNSRA to find optimal rendezvous nodes (RN) for the mobile sink to visit. The RNSRA can select the set of RNs to act as store points for the mobile sink, and search for the optimal multi-hop path between source nodes and rendezvous node, so that the rendezvous node could gather information from sensor nodes periodically. Fitness function with several factors is calculated to find suitable RNs from sensor nodes, and the artificial bee colony optimization algorithm (ABC) is used to optimize the selection of optimal multi-hop path, in order to forward data to the nearest RN. Therefore the energy consumption of sensor nodes is minimized and balanced. Our method is validated by extensive simulations and illustrates the novel capability for maintaining the network robustness against sink moving problem, the results show that the RNSRA could reduce energy consumption by 6% and increase network lifetime by 5% as comparing with several existing algorithms.