排序方式: 共有320条查询结果,搜索用时 187 毫秒
311.
The reversible photoswitched near‐infrared‐(NIR)‐emitting Boron‐dipyrromethene (BODIPY) containing nanparticles are reported. Dithienylethene derivatives are used as the photochromic unit in the nanoparticle to control the on and off of fluorescence BODIPY molecules. As a result, it is demonstrated that these nanoparticles conduct robust reversible modulation of the NIR fluorescence in vitro and in the cell culture with negligible toxicity. This study may offer a new approach to the use of these nanomaterials for numerous photonic and biophotonic applications. 相似文献
312.
Three novel symmetrical 4.4'-difluoro-4-bora-3a,4a-diaza-sindacene(BODIPY) derivatives were synthesized via a general and efficient protocol. These BODIPY dyads bear a diverse aryl linker bridge in the middle and two BODIPY units at the termini. The photophysical properties of these dyads were investigated by ultravioletvisible(UV-Vis) absorption and emission spectroscopy. And their electrochemical properties were studied by cyclic voltammetry. The absorption of these dyads showed slightly blue shift and the intramolecular charge transfer(ICT) state under,vent ultrafast direct surface crossing to the ground state with high degree of rotational freedom. The results will be useful for the further functionalization of these novel symmetrical BODIPY derivatives. 相似文献
313.
Sangwon Ko Cheul Yong Kim Kongara Damodar Hyun Min Lim Jin Ho Kim Chang-Hee Lee Jeong Tae Lee 《Tetrahedron》2018,74(2):287-295
We successfully synthesized eight meso-aryl BODIPYs with 2,6-diethyl- or 1,2,6,7-tetraethyl substituents and characterized their photophysical properties. The steric hindrance resulting from the phenolic group in the meso-aryl moiety and the ethyl groups on the BODIPY core affected the synthesis of dipyrromethanes as an intermediate as well as the UV–Vis absorption and fluorescence emission of the BODIPYs due to the constrained rotation of the aryl ring. The potential use of the meso-hydroxyphenyl BODIPY as a pH sensor was also shown by the pH-dependent fluorescence emissions. 相似文献
314.
Van‐Nghia Nguyen Yubin Yim Sangin Kim Bokyeong Ryu K. M. K. Swamy Gyoungmi Kim Nahyun Kwon C‐Yoon Kim Sungnam Park Juyoung Yoon 《Angewandte Chemie (International ed. in English)》2020,59(23):8957-8962
Novel BODIPY photosensitizers were developed for imaging‐guided photodynamic therapy. The introduction of a strong electron donor to the BODIPY core through a phenyl linker combined with the twisted arrangement between the donor and the BODIPY acceptor is essential for reducing the energy gap between the lowest singlet excited state and the lowest triplet state (ΔEST), leading to a significant enhancement in the intersystem crossing (ISC) of the BODIPYs. Remarkably, the BDP‐5 with the smallest ΔEST (ca. 0.44 eV) exhibited excellent singlet oxygen generation capabilities in both organic and aqueous solutions. BDP‐5 also displayed bright emission in the far‐red/near‐infrared region in the condensed states. More importantly, both in vitro and in vivo studies demonstrated that BDP‐5 NPs displayed a high potential for photodynamic cancer therapy and bioimaging. 相似文献
315.
We have developed and validated a procedure of high sensitivity for the analysis of RNA. The procedure is based on the separation and detection of the 5'-monophosphates of ribonucleosides selectively conjugated with 4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-propionyl ethylene diamine hydrochloride (BODIPY FL EDA) at the 5'-phosphate group using CE with LIF. BODIPY conjugates of the four common ribonucleoside-5'-monophosphates were prepared and subjected to CE-LIF to serve as standard compounds for peak assignment and to develop separation conditions. After digestion of RNA or oligoribonucleotides to 5'-monophosphates by nuclease P1 and fluorescence labeling BODIPY conjugates were detected and resolved by CE-LIF without further purification steps. Comparative CE-LIF analyses with DNA digested to deoxyribonucleoside-5'-monophosphates showed that the assay is equally efficient and sensitive for RNA analysis. Conditions to determine the modified ribonucleosides inosine, xanthosine, pseudouridine and 2'-O-methyladenosine were also established. The limits of detection were in the range of 80-200 pM. After calibrating the assay with oligoribonucleotides, pseudouridine was quantified in total RNA of Drosophila, human liver, human kidney and t-RNA of Saccharomyces cerevisiae. These studies demonstrate good potential of fluorescence labeling of ribonucleoside-5'-monophosphates with BODIPY FL EDA and detection by CE-LIF to determine RNA composition with high accuracy and sensitivity. 相似文献
316.
Hiroshi SHINOKUBO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2014,90(1):1-11
Borylated functional π-systems are useful building blocks to enable efficient synthesis of novel molecular architectures with beautiful structures, intriguing properties and unique functions. Introduction of boronic ester substituents to a variety of extended π-systems can be achieved through either iridium-catalyzed direct C–H borylation or the two-step procedure via electrophilic halogenation followed by palladium-catalyzed borylation. This review article focuses on our recent progress on borylation of large π-conjugated systems such as porphyrins, perylene bisimides, hexabenzocoronenes and dipyrrins. 相似文献
317.
以叠氮乙酸乙酯和联二噻吩甲醛为原料,合成了联二噻吩并吡咯单体,之后在酸催化下与4-N,N-二甲基氨基苯甲醛缩合并与三氟化硼配位,得到一个新型的BODIPY染料SY。采用1H NMR、质谱以及元素分析对其结构进行了表征。化合物SY在二氯甲烷中的最大吸收和发射波长分别为654和689 nm;采用荧光光谱滴定方法研究了它对pH值的响应,酸性条件下N,N-二甲基苯氨基团发生质子化,抑制了光诱导电子转移对BODIPY母体的荧光淬灭,其溶液的荧光显著增强,染料SY可以作为近红外的pH值荧光探针。 相似文献
318.
Xi Chen Yu-Cong Liu Jing-Jing Cui Fang-Ying Wu Qiang Xiao 《Molecules (Basel, Switzerland)》2021,26(19)
Pathogenic E. coli infection is one of the most widespread foodborne diseases, so the development of sensitive, reliable and easy operating detection tests is a key issue for food safety. Identifying bacteria with a fluorescent medium is more sensitive and faster than using chromogenic media. This study designed and synthesized a β-galactosidase-activatable fluorescent probe BOD-Gal for the sensitive detection of E. coli. It employed a biocompatible and photostable 4,4-difluoro-3a,4a-diaza-s-indancene (BODIPY) as the fluorophore to form a β-O-glycosidic bond with galactose, allowing the BOD-Gal to show significant on-off fluorescent signals for in vitro and in vivo bacterial detection. This work shows the potential for the use of a BODIPY based enzyme substrate for pathogen detection. 相似文献
319.
以吡啶-2-甲酸(4-甲酰基苯酚)酯代替对羟基苯甲醛,将对羟基苯基引入到BODIPY染料的3-位,以高产率得到一个BODIPY类探针2。探针2易溶解到各种有机溶剂中,在甲醇溶液中的最大吸收和发射波长分别为570和585 nm,荧光量子产率达到0.9。当溶液的pH值从酸性过渡到碱性时,对羟基苯乙烯基团会慢慢失去质子,其溶液最大吸收波长发生红移,荧光发生淬灭,而且溶液颜色也发生明显的变化。因此,探针2可作为一种"裸眼"可视化的pH探针。此外,探针2对Fe~(3+)也有明显的响应,在溶液中加入Fe~(3+),探针2分子结构中乙烯基团发生断裂,其溶液最大吸收波长和最大发射峰均发生蓝移。因此,探针2也可以作为Fe~(3+)的比率型探针。同时探针2毒性较低、渗透性好、对Fe~(3+)选择性高,可以应用到细胞中检测Fe~(3+)的含量。 相似文献
320.
Dr. Le Zeng Lin-Han Jiang Jia-Yao Li Prof. Ling Huang Dr. Yongzhi Chen Nuo Yu Dr. Lei Wang Dr. Kai Huang Dr. Jing Peng Prof. Gang Han 《Angewandte Chemie (International ed. in English)》2023,62(11):e202218341
Metal-free long-wavelength light-driven prodrug photoactivation is highly desirable for applications such as neuromodulation, drug delivery, and cancer therapy. Herein, via triplet fusion, we report on the far-red light-driven photo-release of an anti-cancer drug by coupling the boron-dipyrromethene (BODIPY)-based photosensitizer with a photocleavable perylene-based anti-cancer drug. Notably, this metal-free triplet fusion photolysis (TFP) strategy can be further advanced by incorporating an additional functional dopant, i.e. an immunotherapy medicine inhibiting the indoleamine 2,3-dioxygenase (IDO), with the far-red responsive triplet fusion pair in an air-stable nanoparticle. With this IDO inhibitor-assisted TFP system we observed efficient inhibition of primary and distant tumors in a mouse model at record-low excitation power, compared to other photo-assisted immunotherapy approaches. This metal-free TFP strategy will spur advancement in photonics and biophotonics fields. 相似文献