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101.
Yang Xu Ming Wu Yang Liu Prof. Dr. Xi‐Zeng Feng Prof. Dr. Xue‐Bo Yin Prof. Xi‐Wen He Prof. Yu‐Kui Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(7):2276-2283
Carbon dots (Cdots) are an important probe for imaging and sensing applications because of their fluorescence property, good biocompatibility, and low toxicity. However, complex procedures and strong acid treatment are often required and Cdots suffer from low photoluminescence (PL) emission. Herein, a facile and general strategy using carbonization of precursors and then extraction with solvents is proposed for the preparation of nitrogen‐doped Cdots (N‐Cdots) with 3‐(3,4‐dihydroxyphenyl)‐L ‐alanine (L ‐DOPA), L ‐histidine, and L ‐arginine as precursor models. After they are heated, the precursors become carbonized. Nitrogen‐doped Cdots are subsequently extracted into N,N′‐dimethylformamide (DMF) from the carbogenic solid. A core–shell structure of Cdots with a carbon core and the oxygen‐containing shell was observed. Nitrogen has different forms in N‐Cdots and oxidized N‐Cdots. The doped nitrogen and low oxidation level in N‐Cdots improve their emission significantly. The N‐Cdots show an emission with a nitrogen‐content‐dependent intensity and Cdot‐size‐dependent emission‐peak wavelength. Imaging of HeLa cells, a human cervical cancer cell line, and HepG2 cells, a human hepatocellular liver carcinoma line, was observed with high resolution using N‐Cdots as a probe and validates their use in imaging applications and their multicolor property in the living cell system. 相似文献
102.
Xiangtang Li Ruichuan Yin Hang Hu Yingju Li Prof. Xiaofei Sun Prof. Sudhansu K. Dey Prof. Julia Laskin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(50):22574-22577
Ambient ionization based on liquid extraction is widely used in mass spectrometry imaging (MSI) of molecules in biological samples. The development of nanospray desorption electrospray ionization (nano-DESI) has enabled the robust imaging of tissue sections with high spatial resolution. However, the fabrication of the nano-DESI probe is challenging, which limits its dissemination to the broader scientific community. Herein, we describe the design and performance of an integrated microfluidic probe (iMFP) for nano-DESI MSI. The glass iMFP, fabricated using photolithography, wet etching, and polishing, shows comparable performance to the capillary-based nano-DESI MSI in terms of stability and sensitivity; a spatial resolution of better than 25 μm was obtained in these first proof-of-principle experiments. The iMFP is easy to operate and align in front of a mass spectrometer, which will facilitate broader use of liquid-extraction-based MSI in biological research, drug discovery, and clinical studies. 相似文献
103.
Xiaobo ZhouYunguo Lu Jian-Fa ZhuWing-Hong Chan Albert W.M. LeePui-Shan Chan Ricky N.S. WongN.K. Mak 《Tetrahedron》2011,67(19):3412-3419
By appending a pair of carboxamidoquinoline pendants onto 1,2-diaminocyclohexane scaffold via N-alkylation, multifunctionalized ACAQ was designed and synthesized as a water soluble fluorescent ratiometric chemosensor for Zn2+. In 50% aqueous methanol buffer pH 7.4 solution, upon excitation at 316 nm, ACAQ (5 μM) displayed a selective ratiometric fluorescence changes with a shift from 410 to 490 nm in response to the interaction with Zn2+. After binding with 1 equiv of Zn2+, ACAQ exhibited a 12-fold enhancement in I490/I410 characterized by a clear isoemissive point at 440 nm. The metal sensor binding mode was established by Job’s plot and the combined fluorescence and 1H NMR spectroscopic method. The selectivity of the probe toward biological relevant cations and transition metal ions was proven to be good. In addition, the interference caused by Cu2+ and Cd2+ in the quantitation of Zn2+ can be completely eliminated by the use of diethyldithiocarbamate as the screening agent. Exploitation of ACAQ as the sensing probe, ratiometric determination of Zn2+ with the limit of detection (LOD) at 28.3 nm can be realized. In addition, the unique responsive properties of the probe toward Fe3+ and Zn2+ were used to construct a fluorescent switch. The membrane permeability of ACAQ to living cells and bio-imaging of Zn2+ were demonstrated. 相似文献
104.
Sensitive, rapid and inexpensive chemiluminescence (CL) imaging has been developed based on molecular imprinted polymer (MIP) sensing elements. Imprinted uniform microspheres were synthesized by precipitation polymerization. Microtiter plates (96 wells) were coated with polymer microspheres imprinted with trans-resveratrol, which were fixed in place using poly(vinyl alcohol) (PVA) as glue. The amount of polymer-bound trans-resveratrol was quantified using imidazole (IMZ)-catalyzed peroxyoxalate chemiluminescence (PO-CL) reaction. The light produced was then measured with a high-resolution CCD camera. Calibration curve corresponding to analyte concentration ranging from 0.3 to 25 μg mL−1 was obtained with a limit of detection 0.1 μg mL−1. These results showed that the MIP-based CL imaging sensor can become a useful analytical tool for quick simultaneous detection of trans-resveratrol in a large number of real samples. 相似文献
105.
Zengxia Zhao Yuning Han Chenghong Lin Dong Hu Fang Wang Prof. Xiaolan Chen Prof. Zhong Chen Prof. Nanfeng Zheng 《化学:亚洲杂志》2012,7(4):830-837
Lanthanide‐doped upconversion nanoparticles (UCNPs) have attracted considerable attention for their application in biomedicine. Here, silica‐coated NaGdF4:Yb,Er/NaGdF4 nanoparticles with a tetrasubstituted carboxy aluminum phthalocyanine (AlC4Pc) photosensitizer covalently incorporated inside the silica shells were prepared and applied in the photodynamic therapy (PDT) and magnetic resonance imaging (MRI) of cancer cells. These UCNP@SiO2(AlC4Pc) nanoparticles were uniform in size, stable against photosensitizer leaching, and highly efficient in photogenerating cytotoxic singlet oxygen under near‐infrared (NIR) light. In vitro studies indicated that these nanoparticles could effectively kill cancer cells upon NIR irradiation. Moreover, the nanoparticles also demonstrated good MR contrast, both in aqueous solution and inside cells. This is the first time that NaGdF4:Yb,Er/NaGdF4 upconversion‐nanocrystal‐based multifunctional nanomaterials have been synthesized and applied in PDT. Our results show that these multifunctional nanoparticles are very promising for applications in versatile imaging diagnosis and as a therapy tool in biomedical engineering. 相似文献
106.
Dr. Qingqing Miao Dr. David C. Yeo Dr. Christian Wiraja Dr. Jianjian Zhang Xiaoyu Ning Prof. Chenjie Xu Prof. Kanyi Pu 《Angewandte Chemie (International ed. in English)》2018,57(5):1256-1260
Early detection of skin diseases is imperative for their effective treatment. However, fluorescence molecular probes that allow this are rare. The first activatable near‐infrared (NIR) fluorescent molecular probe is reported for sensitive imaging of keloid cells, skin cells from abnormal scar fibrous lesions. As keloid cells have high expression levels of fibroblast activation protein‐alpha (FAPα), the probe (FNP1) is designed to have a caged NIR dye and a FAPα‐cleavable peptide substrate linked by a self‐immolative segment. FNP1 can quickly and specifically turn on its fluorescence at 710 nm by 45‐fold in the presence of FAPα, allowing it to effectively recognize keloid cells from normal skin cells. Integration of FNP1 with a simple microneedle‐assisted topical application enables sensitive detection of keloid cells in metabolically‐active human skin tissue with a theoretical limit of detection down to 20 000 cells. 相似文献
107.
Yong Li Yingzheng Shu Muwen Liang Dr. Xilei Xie Dr. Xiaoyun Jiao Prof. Xu Wang Prof. Bo Tang 《Angewandte Chemie (International ed. in English)》2018,57(38):12415-12419
Carbon monoxide (CO) is proposed as an active pharmaceutical agent with promising pharmaceutical prospects, as it has been involved in multifaceted modulation of diverse physiological and pathological processes. However, questions remain for therapeutic application of inhaled CO attributed to the inherent great affinity between CO and hemoglobin. Therefore, a robust platform with the function of CO transport and controllable release, depending on the local status of an organism, is of prominent significance for effectively avoiding the side effects of CO inhalation and optimizing the biological regulation function of CO. Utilizing the oxidative stress biomarker H2O2 as a trigger and combining with photo‐control, a two‐photon H2O2‐activated CO photoreleaser, FB, featuring highly sensitive and specific H2O2 sensing and photocontrollable CO release, was developed and the vasodilation effect of CO against angiotensin II was demonstrated. 相似文献
108.
109.
110.
《Arabian Journal of Chemistry》2022,15(11):104302
Traditional Chinese medicine (TCM) is the key to unlock treasures of Chinese civilization. TCM and its compound play a beneficial role in medical activities to cure diseases, especially in major public health events such as novel coronavirus epidemics across the globe. The chemical composition in Chinese medicine formula is complex and diverse, but their effective substances resemble “mystery boxes”. Revealing their active ingredients and their mechanisms of action has become focal point and difficulty of research for herbalists. Although the existing research methods are numerous and constantly updated iteratively, there is remain a lack of prospective reviews. Hence, this paper provides a comprehensive account of existing new approaches and technologies based on previous studies with an in vitro to in vivo perspective. In addition, the bottlenecks of studies on Chinese medicine formula effective substances are also revealed. Especially, we look ahead to new perspectives, technologies and applications for its future development. This work reviews based on new perspectives to open horizons for the future research. Consequently, herbal compounding pharmaceutical substances study should carry on the essence of TCM while pursuing innovations in the field. 相似文献