A near-infrared fluorescent probe for monitoring fluvastatin-stimulated endogenous H2S production

Most reported fluorescent probes have limitations in practical applications in living systems due to the strong autofluorescence background,construction of probes with near-infrared(NIR) fluorescence emission is an accessible approach for addressing this challenge.We here designed a NIR fluorescent probe for monitoring the endogenous production of H_2S in living cells.The designed probe showed significant NIR fluorescence turn-on response to H_2S with high selectivity,enabling the sensitive detection H_2S.Importantly,the probe could be applied in monitoring the endogenous production of H_2S in raw 264.7 macrophages.This study showed that fluvastatin can promote the activity of cystathionineγ-lyase(CSE) for generation H_2S.     

Synthesis and Properties of Novel Fluorescence Probe Based on 1,8-Naphthalimide for Detection of Hydrogen Sulfide

Two fluorescence-enhanced probes,4-(2,4-dinitrophenoxy)-N-(2-hydroxyethyl)-1,8-naphthalimide(NTE-1)and 4-(2,4-dinitrophenoxy)-N-[4-(2,4-dinitrophenoxy)phenyl]-1,8-naphthalimide(NTE-2),have been designed and synthesized for detection of H2S.4-Hydroxy-1,8-naphthalimide as fluorophore in combination with 2,4-dinitrophenyl ether as H2S response site constructed the fluorescence probes.The consequences showed that both NTE-1 and NTE-2 displayed large red-shift(excess 100nm)in absorption spectra and more than 30-fold fluorescence enhancement in response to H2S.Moreover,the dual site probe,NTE-2,displayed wider linear range between fluorescence intensity and concentration of H2S(0-40μmol/L)compared with single site probe,which can be applied to quantita-tive detection of high concentration of H2S.The photomduced electron transfer(PET)response mechanism of probe was further studied by analyzing the distributions of molecular orbital.Importantly,the probes have potential practical applications in the detection of H2S.     

以苯并咪唑萘酰亚胺为荧光团高选择快速检测H2S的荧光探针

以1,8-萘二甲酸酐为起始原料合成一种萘酰亚胺衍生物3-叠氮基-7H-苯并[de]苯并[4,5]咪唑[2,1-a]异喹啉(DBNG),利用傅里叶变换红外光谱(FT-IR)和核磁共振波谱(NMR)等测试手段确定其结构,并将其作为小分子荧光探针用于检测H2S,系统研究了其荧光特性,结合理论计算,探究其可能的检测机制.结果表...     

Two-photon dual-channel fluorogenic probe for in situ imaging the mitochondrial H2S/viscosity in the brain of drosophila Parkinson’s disease model

H₂S is an essential gas signal molecule in cells, and viscosity is a key internal environmental parameter. Recent studies have shown that H₂S acts as a cytoarchitecture agent and gas transmitter in many tissues, e.g., as a regulator of neuroendocrine in the brain for mediating vascular tone in blood vessels. Mitochondrial viscosity is an important parameter for judging whether mitochondrial function is normal. It has been reported that oxidative stress and mitochondrial dysfunction are connected with Parkinson’s disease (PD), and the protective role of H₂S in PD models has been extensively demonstrated. Herein, Mito-HS, a new two-photon fluorescent probe was demonstrated to detect cross-talk between the two channels of mitochondrial viscosity and H₂S content. Moreover, this probe could detect the relative amount of and changes in mitochondrial H₂S in situ due to the reduced mitochondrial targeting ability after reaction with H₂S. The results show that H₂S in mitochondria is inversely related to viscosity. The PD model has a lower H₂S in mitochondria and a higher mitochondrial viscosity than did the normal. This result is important for our deep understanding of PD and its causes.     

Cascade reaction-based fluorescent probe for detection of H2S with the assistance of CTAB micelles

We report a turn-on fluorescent probe for H₂S through a cascade reaction using a new trap group 4-(bromomethyl)benzoate, based on excited-state intramolecular proton transfer (ESIPT) sensing mechanism. The probe showed good selectivity and high sensitivity towards H₂S and it was capable of detecting and imaging H₂S in living HeLa cells, indicating its potential biological applications.     

硫化氢对活性炭脱除单质汞的影响

H₂S是煤气中的含硫成分,活性炭能否催化氧化煤气中的H₂S形成活性硫,以促进H₂S和Hg⁰的协同脱除是值得研究的。 本文首先通过程序升温脱附和热力学分析了低温情况下H₂S对活性炭脱除Hg⁰的影响。 在较低吸附温度130 ℃下,H₂S不仅不能作为硫源,还使活性炭对Hg⁰的吸附显著减弱,这主要是由于H₂S对活性炭表面的吸附氧的消耗以及H₂S对含氧官能团的氧的取代反应造成的。 在此基础上,进一步研究了高温下H₂S对活性炭的影响,高温也不能使活性炭有效渗入单质硫。 所以无论低温还是高温情况下,利用H₂S作为硫源使Hg⁰以HgS的形式脱除并不是活性炭脱汞的可行手段。 本文揭示了较宽的温度范围内H₂S对单纯的活性炭脱除Hg⁰的影响机理,能为用于煤气脱汞的活性炭的设计以及作为负载时机理研究提供支持作用。     

垃圾衍生燃料热解半焦气化过程中HCl与H2S析出规律

通过水平管式气化炉和化学吸收法,对比研究了矿化垃圾热解半焦（ARC）和常规垃圾热解半焦（NRC）在水蒸气和CO₂气化过程中腐蚀性气体（HCl和H₂S）的析出特性,考察了气化温度、气化介质类型和流量对腐蚀性气体析出特性的影响。当气化温度升至950℃,ARC在水蒸气气化过程中的碳气化率、HCl和H₂S产率分别为66.1%、100%和74.9%,而其在CO₂气化过程中的碳气化率、HCl和H₂S产率分别为77.8%、100%和2.9%;NRC在水蒸气气化过程中的碳气化率、HCl和H₂S产率分别为98.8%、100%和53.7%,而其在CO₂气化过程中的碳气化率、HCl和H₂S产率分别为100%、96.2%和10.3%。以NRC为原料,考察了水蒸气和CO₂流量对其HCl和CO₂析出特性的影响。NRC的HCl和H₂S产率均随水蒸气流量增加而增加,但当水碳比大于等于3.3时,其促进作用不再明显。NRC的HCl产率随CO₂流量的增加而增加,而H₂S产率随CO₂流量的增加而减小。     

Near-infrared photothermal release of hydrogen sulfide from nanocomposite hydrogels for anti-inflammation applications

A novel near-infrared light photothemal-activated H2S-donating nanocomposite hydrogel was developed,through combination of a thermo-labile H2S donor and photothermal nanoparticles in agarose hydrogel.The polyethylenimine dithiocarbamate polymer,a thermo-labile compound,was synthesized as a novel H2S donor.The combination of a thermo-labile hydrogen sulfide donor and photothermal nanoparticles enabled the generation of H2S in agarose hydrogel upon irradiation with near-infrared light.The ability to modulate the photoirradiation for controlled generation and spatiotemporally release of H2S are its specific advantages.This photothermal spatiotemporally controlled H2S-releasing strategy was successfully applied to anti-inflammation treatment in a rat model,demonstrating its utility as a novel H2S-based therapeutic approach.     

联苯类比率型荧光探针检测水中硫化氢

以叠氮基为识别基团,4.4'-联苯二甲酸为初始原料,合成了一种可用于H_2S检测的联苯类比率型荧光探针2-叠氮基-4,4'-联苯二甲酸乙酯(WN),并通过~1H NMR、~(13)C NMR以及MS等技术手段对其结构进行了表征。以检测水溶液中硫化氢为目的,系统地研究了其荧光特性。研究结果表明,WN对硫化氢具有高选择性和灵敏度,且对生物硫醇(Cys,Gsh)、活性氧化物(H_2O_2,ClO~-)、各种阴阳离子(H_2PO_4~-,SO_4~(2-),Cl~-,HCO_3~-,CO_3~(2-),Mg~(2+),Zn~(2+),K~+,Ca~(2+),Na~+)有很强的抗干扰能力,在较宽的pH值范围内,仍然表现出良好的荧光性能,在1.1~350μmol/L范围内,NaHS的浓度与荧光强度呈现良好的线性关系,相关系数R~2=0.9943,检出限度为1.07×10~(-6)mol/L。通过对3种不同水样的测试,表明探针WN在水体中H_2S的检测方面具有一定的应用意义。     

基于密度泛函理论下H2S在单原子催化剂V/Ti2CO2上的分解机理研究

In-depth understanding of the mechanisms of hydrogen sulfide (H₂S) adsorption on catalysts during desulfurization from industrial waste gas streams is important for developing effective catalysts to be used in the decomposition of H₂S. In this work, the dissociation behavior of H₂S adsorbed on a single-atom catalyst (Ti or V-decorated Ti₂CO₂ surface) was investigated by performing density functional theory (DFT) calculations. The corresponding diffusion behavior revealed that Ti or V atoms could be dispersed on the Ti₂CO₂ monolayer, without aggregation in the form of single atoms. In addition, analyses of the partial density of states (PDOS), Hirshfeld charges, and electron density difference indicated that the decorated Ti or V atoms led to charge redistribution on the Ti₂CO₂ surface and significantly improved the interaction between the H₂S gas molecules and Ti₂CO₂, thereby enhancing the catalytic activity of V/Ti₂CO₂. In order to gain a deeper understanding of the mechanism of H₂S decomposition (H₂S → HS* + H* → H₂ + S*), a comparative analysis of the results for the decomposition of H₂S on the Ti/Ti₂CO₂ and V/Ti₂CO₂ surfaces was carried out. The catalytic dissociation behavior of H₂S is explained as follows: once H₂S is adsorbed on the V/Ti₂CO₂ or Ti/Ti₂CO₂ surface, it spontaneously dissociates into HS*/H* without any energy barrier on the catalyst surface. Subsequently, the V atoms would not only promote the cleavage of the H-S bond, but also play a major role in the formation of S atoms. Moreover, the rate-limiting step for the entire process proceeded on the Ti/Ti₂CO₂ surface with an energy barrier of 0.86 eV, while that for V/Ti₂CO₂ was 0.28 eV, indicating that the H₂S molecules easily dissociated into S and H₂ on the V/Ti₂CO₂ surface at room temperature. The reaction time for H₂S decomposition on the V/Ti₂CO₂ surface at 500 K was 65.79 ns, which was almost two orders of magnitude higher than that at room temperature. Thus, the decomposition of H₂S on the V-doped Ti₂CO₂ surface is associated very fast kinetics. Furthermore, the S atoms can form elemental sulfur with aggregation on the V/Ti₂CO₂ surface to promote recycling reactions. Compared with previously reported catalytic systems, the single-atom catalyst (SAC) V/Ti₂CO₂ catalyst has greater application prospects in terms of sustainable economy or removal efficiency for H₂S treatment. Our results suggest that V-doped Ti₂CO₂ is an excellent candidate for a highly effective non-noble metal catalyst applicable to H₂S decomposition.      

Hydrodeoxygenation of benzofuran over sulfided and reduced Ni–Mo/γ-Al2O3 catalysts: Effect of H2S

Effect of H₂S on the catalytic performance of the reduced and sulfided Ni–Mo/Al₂O₃ catalysts in hydrodeoxygenation of benzofuran is studied. The steady-state reaction experiments showed a decrease in activity for both reduced and sulfided catalysts when H₂S was introduced into the feed. The reaction conversion of benzofuran over the reduced catalyst still remained superior to that of the sulfided catalyst in the presence of H₂S, however, at high reaction temperatures, the product distribution over the pre-reduced catalyst is similar to the sulfided catalyst. The studies with temperature-programmed desorption (TPD), temperature-programmed reaction (TPRxn) and X-ray photoelectron spectroscopy (XPS) techniques showed a partial sulfidation of the reduced catalysts when exposed to H₂S under reaction conditions, however, the catalyst does not go through a complete conversion to a molybdenum sulfide phase. Instead oxygen–sulfur exchange on the surface leaves behind oxisulfide species, with catalytic activity closely resembling that of the reduced catalysts. The effect of H₂S on the reaction performance is mainly coming from the competitive adsorption between H₂S and benzofuran and the formation of SH groups with decomposition of H₂S at high temperatures.     

Radiation induced scavenging of NOx, SO2, H2S from exhaust gases

The theoretical model of exhaust gases radiation induced oxidation was developed. NO, SO₂ and H₂S concentrations curves vs dose calculated by use of this model for mixtures containing N₂ (80.5%), O₂ (11%), H₂O (8.4%), NO (100–600 ppm), SO₂ (150–500 ppm) and H₂S (300–1000 ppm) have been obtained. It has been shown that NO and SO₂ conversion reactions with acids formation go simultaneously with oxidizing reaction of H₂S giving SO₂ as an intermediate substance. These processes were evaluated for different initial concentrations of NO, SO₂ and H₂S. Data established by our simulation calculations show that the electron beam process can be judged as a promising technology for simultaneous removal of SO₂, NO and H₂S from exhaust gases.     

硫化氢对钴改性活性焦脱除煤气中汞的影响机理

采用等体积浸渍煅烧法制备钴改性活性焦(Co-AC),并采用BET、XRD等分析手段进行表征。 利用固定床吸附实验台,研究了模拟煤气(N₂、H₂、CO、H₂S)气氛下汞的吸附特性,重点关注H₂S对汞吸附的影响。 结果表明,5%负载量的Co-AC在120 ℃和H₂S作用下具有优异的脱汞能力,2 h内平均脱汞效率高达97.8%。 此外基于密度泛函理论,首先计算了H₂S、HS及S在Co₃O₄(110)表面的吸附能及键长,通过比较H—S键键长的变化得出H₂S会逐步解离成HS与S,然后将优化后的S-Co₃O₄(110)作为Hg的吸附基底,研究其吸附特性,得出Hg与S反应生成稳定的HgS,吸附能为-3.503 eV,证明了汞的吸附遵循Eley-Rideal机制。 Co-AC吸附剂在高温下脱汞性能受到极大的抑制,因为随吸附温度升高,表面活性硫的减少及硫和汞的反应平衡常数下降显著,导致汞的脱除能力下降。 本文采用了实验加模拟的手段,探明了H₂S存在时Hg⁰在钴基吸附剂表面的反应机理,为协同脱除煤气中的H₂S和Hg⁰提供了理论指导。     

近红外荧光探针检测金属离子、小分子和生物大分子

荧光探针技术是近年来发展迅速的一种荧光分析方法,具有灵敏度高、选择性好、操作简便和响应迅速等特点,受到环境及生命科学领域的青睐.随着荧光探针技术的发展,近红外一区荧光探针由于具有发射波长长(600～ 900 nm)、对细胞损伤小、组织穿透性强和自发荧光背景低等优点,被广泛应用于细胞、组织等复杂生物体系中生物分子的检测、...     

Photoabsorption spectra of H2S, CH3SH and SO2 near the sulfur K edge

Photoabsorption spectra of the isolated sulfur containing molecules H₂S, CH₃SH and SO₂ are measured at high resolution near the sulfur K edge, using synchrotron radiation. Resonances are observed in the discrete and continuum parts of the spectra. The most intense resonances are shown to result from virtual orbital effects on the basis of comparisons with the L edge photoabsorption spectra (H₂S, SO₂), the equivalent core model (SO₂) and low-energy electron scattering measurements (H₂S, SO₂).     

LaCoO3对H2S选择氧化性能的影响

使用溶胶-凝胶法制备了LaCoO₃催化剂,采用XRD、BET和XPS等方式对催化剂进行了表征,考察了该催化剂制备过程中煅烧温度、表面活性剂PEG-6000和PEG-20000含量对其H₂S选择氧化制硫磺反应催化活性的影响。结果表明,表面活性剂PEG-6000及PEG-20000的添加能明显提高LaCoO₃的催化活性。0.02 mol La（NO₃）₃+0.02mol Co（NO₃）₂溶液中添加0.30 g PEG-20000、煅烧温度为650℃时所制备的LaCoO₃催化活性最好;在最佳反应温度260℃下,H₂S的转化率达到96.10%,硫选择性为93.77%。     

超声对多相光催化光解H2S作用的初步探讨

70年代后期,以太阳能化学转化和贮存为主要背景的微多相光催化-催化学科的一个新领域,逐渐发展起来,微多相光催化过程与光电化学过程有着相似的原理,1979年,Bard最早把微电极模型引入到微多相光催化中来^[1],半导体微粒光催化剂,就其电荷转移机制而言,可视为短路的光电化学池,Honda和Frank以一直径为4.8mm的CdS的单晶圆片制成的光化学二极管,浸在电解质中,成功地进行了光解水制氢的研究^[2],这均从实验上演示了微多相光催化体系的光电化学特征.     

Design of a novel mitochondria targetable turn-on fluorescence probe for hydrogen peroxide and its two-photon bioimaging applications

Considering that hydrogen peroxide (H₂O₂) plays significant roles in oxidative stress, the cellular signal transduction and essential biological process regulation, the detection and imaging of H₂O₂ in living systems undertakes critical responsibility. Herein, we have developed a novel two-photon fluorescence turn on probe, named as Pyp-B for mitochondria H₂O₂ detection in living systems. Selectivity studies show that probe Pyp-B exhibit highly sensitive response toward H₂O₂ than other reactive oxygen species (ROS) and reactive nitrogen species (RNS) as well as biologically relevant species. The fluorescence colocalization studies demonstrate that the probe can localize in the mitochondria solely. Furthermore, as a bio-compatibility molecule, the highly selective and sensitive of fluorescence probe Pyp-B have been confirmed by its cell imaging application of H₂O₂ in living A549 cells and zebrafishes under the physiological conditions.     

耐硫甲烷化中H2S浓度对MoO3/Al2O3和CoO-MoO3/Al2O3催化剂的影响

在0 到12 mL·L^-1 (体积分数φ=0.00%-1.20%) 范围内考察了不同H₂S 浓度对25% (质量分数, w)MoO₃/Al₂O₃和5% (w) CoO-25%MoO₃/Al₂O₃催化剂甲烷化性能的影响. 结果表明, 5%CoO-25%MoO₃/Al₂O₃的甲烷化活性随H₂S浓度的增加单调上升, 而25%MoO₃/Al₂O₃对H₂S浓度并不敏感. 对比这两种催化剂发现, 只有在H₂S浓度高于0.40% (φ) 时, 在25%MoO₃/Al₂O₃中添加Co助剂才会有促进作用; H₂S浓度低于0.40% (φ)时, Co助剂会抑制25%MoO₃/Al₂O₃催化剂的甲烷化活性. 分别对反应前后的催化剂表征发现, H₂S浓度的改变不会对两种催化剂的物理结构产生明显的影响, 而是通过影响催化剂表面的金属硫化物活性位来影响催化剂的甲烷化性能. 耐硫甲烷化反应体系中较高的硫含量下Co助剂才表现出对25%MoO₃/Al₂O₃催化剂的促进作用. 该研究明确了在MoO₃/Al₂O₃催化剂中添加Co助剂的硫化氢浓度范围, 为工业上选择合适的催化剂提供了依据.     

H2S气敏电极的研制、性能及其初步应用

本文报告了用全固态Ag₂S电极做指示电极和全固态氟离子电极做参比电极所研制的H₂S气敏电极的结构、性能及其在印染污水分析中的初步应用。电极的线性范围5×10^-8-1×10^-2MS^2-,响应快,重现性较好。除浓度较高的CN^-、I^-和CNS^-有干扰外,其他常见阴离子无干扰。对印染污水用电极悬空测定(加入稀释法),试液不需任何处理,也不沾污电极。方法简便、快速,能满足控制分析要求。