In physiological processes, hypochlorous acid can regulate in vitro signaling molecules as one kind of reactive oxygen species (ROS). Serious diseases, such as cardiovascular disorders, neurodegenerative diseases, Alzheimer's disease, and cancers are usually concerned with the abnormal levels of hypochlorous acid in human bodies. Herein, we report a new probe DPH-BP for HClO, which consists of a benzo[5]helicene-pyridine fluorophore and benzyl-benzeneboronic acid pinacol ester as HClO reaction sites. The structural motifs combined with chromogenic media and fluorescence become a single-molecule sensor response in aqueous solutions. In the presence of HClO, this probe shows a remarkable blue shift of fluorescence from 536 to 452 nm in an aqueous solution and obvious fluorescence color change from yellow to blue. In the same conditions, almost no response can be recorded with the other common ROS/RNS, such as H2O2, TBHP, (OH)-O-center dot, t-BuO center dot, ONOO-, and O-2(center dot-). As we have designed, the oxidation of phenylboronic ester by HClO induces the cleavage of the benzyl in DPH-BP, which has been proven by H-1 NMR spectra and density functional theory calculations. To the best of our knowledge, this is the first report of the analysis of HClO using the oxidation of benzyl-benzeneboronic acid pinacol ester.

Hydrogen sulfide shows great importance in various physiological and biochemical processes. The development of fluorescence probes for facile and efficient detection of H2S has attracted increasing attention of researchers. Herein, we synthesized two fluorescence probes based on simple naphthalene structure for detection of H2S. Upon reaction with H2S, the probe DN-DM exhibited a red fluorescence emission with large Stokes shift. The probe showed high sensitivity, pH insensitivity and good selectivity for H2S over other analytes including common biothiols. The detection mechanism was based on the thiolysis of the dinitrophenyl ether moiety, which was confirmed by 1H NMR spectral analysis. The DFT calculation was also performed for a deeper understanding of the photophysical properties. In addition, these probes showed good cell-membrane permeability and could be utilized for detection of H2S in living cells.

The quadruple hydrogen bonding UPy units are designed to conjugate with unsubstituted PDI to exhibit bright red emission in aggregated state, together with temperature-dependent ratiometric fluorescence property in solution and hydrogels.

By using ethylenediamine (ED) with nitric acid (NA) and formic acid (FA) as raw materials, two types of new carbon dots (CDs) were prepared using microwave method. The as-prepared CDs showed excellent water solubility and photoluminescence properties. The optimum excitation wavelength and emission wavelength of new CDs were at 430 nm and 500 nm (for CDs fabricated with ED and NA) and at 480 nm and 570 nm (for CDs synthesized with ED and FA), respectively. Dyeing the oral tissue with these new CDs was found to be an effective means to stain oral tissue sections. The cell morphology and distribution of the oral tissues can be clearly observed under a fluorescence microscopy. Compared with the hematoxylin-eosin (HE) staining method, a common staining method in biopsy, the dyeing operation of the new CDs is simpler with clearer imaging effect. The difference in cell morphology and distribution between normal oral tissues and pathological oral tissues was observed under a fluorescence microscope by CDs staining to distinguish normal tissues from pathological tissues. Thus, a novel method for detecting oral cancer was developed.

合成了二硫化钼/磺化聚苯胺复合材料(SAT-MoS2)并通过红外光谱(FT-IR)、扫描电镜(SEM)、电化学测试进行了表征.一方面,SAT具有良好的导电性且可以增大MoS2的分散性和溶解性;另一方面,MoS2自身具有比表面积大、活性位点多的优点,从而使制备出的复合材料具有良好的电化学性能.在最优的实验条件下,通过差分脉冲伏安法(DPV)可以实现对硝基苯酚的灵敏性检测.检测范围0?1～50μmol·L－1检测限低至1?6×10－8mol·L－1,并且该复合材料修饰电极具有良好的稳定性.

New carbon dots (CDs) were prepared by a microwave method using m-trihydroxybenzene and dilute sulphuric acid as raw materials. The as-prepared CDs exhibited excellent water solubility and photoluminesence properties. The optimum excitation and emission wavelengths of the new CDs were at 365 nm and 465 nm, respectively. The fluorescence of the new CDs experienced remarkable changes in the presence of Britton-Robinson (BR) buffer solution with different pH values under 4°C after reacting for 70 min. In addition, a linear relationship between the logarithm of the relative fluorescence intensity ratio [lg(IF /IFo )] of CDs and the pH values of the sensing system ranging 1.81-5.72 was obtained, with a correlation coefficient of 0.9933. Thus, a sensitive and simple method to detect the pH value of solution was developed. Furthermore, the analytical application of detecting the concentration of acetic acid in vinegar was investigated. The detection values were found similar to the reference values, fully demonstrating a good linear relationship between the logarithm of the relative fluorescence intensity ratio of the CDs and the pH value of the system. Hence, the method could be used to detect the concentration of acetic acid in vinegar.

聚硫堇/金属有机骨架复合材料PTh/Cu(tpa)被制备并用于灵敏的检测对硝基苯酚(4-NP).通过红外光谱(FT-IR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等仪器对Cu(tpa)及PTh/Cu(tpa)进行了表征.相对于裸电极及单一材料修饰电极,PTh/Cu(tpa)复合材料修饰电极对4-NP的检测具有更好的电化学响应,这可能归因于Cu(tpa)自身具有较大的比表面积,而聚硫堇的存在增加了Cu(tpa)的导电性,使得PTh/Cu(tpa)复合材料兼具有大的比表面积和良好导电性的性能,从而对目标物表现出协同的催化作用.在最优条件下,通过差分脉冲伏安法(DPV)对4-NP进行了检测,还原峰电流与4-NP的浓度在3×10-7～1×10-5 mol·L-1范围内呈良好的线性关系,检出限为7.1×10-8 mol·L-1.

An easily available novel fluorescent probe has been synthesized by reacting rhodamine hydrazide and 2-(thiophen-2-yl)acetyl chloride. Upon mixed with Fe3+ in aqueous solution, the dramatic enhancement of fluorescence intensity as well as the color change of the solution were observed. Significantly, the probe displayed highly selective and sensitive recognition ability toward Fe3+ with a limit of detection (LOD) down to 10(-73) M. The Job's plot indicated the formation of 1:1 complex between the probe and Fe3+, and the complexation stability constant can be calculated as 2.95 x 10(4) M-1. The presence of common coexisting alkali, alkaline earth, and transition metal ions showed small or no interference to the detection of Fe3+. All these unique features make it particularly favorable for cellular Fe3+ imaging applications. The confocal fluorescent images demonstrated that the probe was cell-permeable and could be used for highly sensitive monitoring of Fe3+ levels in living cells with satisfying resolution. (c) 2017 Elsevier B.V. All rights reserved.

A novel visible light excitable chemosensor based on a rhodamine 6G naphthylurea conjugate was successfully synthesized, which shows highly selective and sensitive recognition ability toward H2PO4- in H2O-CH3CN (1/1, v/v). In response to H2PO4-, the probe provided remarkable fluorescence intensity change and clear color change from colorless to pink and the background anions showed small or no interference. The confocal fluorescent images demonstrated that the probe was cell-permeable and could effectively detect intracellular dihydrophosphate in living cells. (C) 2017 Elsevier B.V. All rights reserved.

Ten types of industrial-grade polystyrene products were determined by using13C-NMR methods and the intensity of the carbon spectrum peak were normalized. The relationship between physical performance and chemical component of NMR characteristic information of polystyrene were studied. Then the polymeromics concept is put forward. As calculus examples,a kind of "add up zigzag in equal areas weighted" coding algorithm,15 codes were got about material performance. Code shows that the physical properties of the polystyrene material has a better consistency with NMR codes. The NMR polymeromics has a promising prospect.

通过酰化反应合成了以罗丹明内酰胺结构为母体的化学传感器,并通过紫外分光光度计,荧光分光光度计检测了其对三价铁离子的识别能力.其在乙醇和水的混合溶液中对铁离子有很好的选择性.由荧光光谱显示,在铁离子存在下在580 nm处出现较强的吸收峰,然而加入其它离子,荧光强度没有明显变化.络合化学计量比为1:1,铁离子的加入导致溶液颜色变红,其可以作为识别铁离子的“裸眼”荧光传感器.

In order to determine the source of oversulfated chondroitin sulfate(OSCS) in contaminated heparin sodium,the three sections of intestine mucosa,serosa and casing which were isolated from the pig intestine,were digested by trypsin.The products were analyzed by 1HNMR method.The results indicated that principal component of intestine mucosa was heparin sodium,also including dermatan sulfate and chondroitin sulfates C.In the serosa section including little chondroitin sulfates C,the content of heparin sodium was equal to that of dermatan sulfate.The principal component of casing was dermatan sulfate,also including heparin sodium,chondroitin sulfates C and chondroitin sulfates A.OSCS was not discovered in intestine mucosa,serosa and casing.

The structure,properties and source of oversulfated chondroitin sulfate(OSCS),which exists in contaminated heparin sodium,are introduced.And the research progress of its determination methods are reviewed.

1引言肝素钠是一种由葡萄糖胺,L-艾杜糖醛苷、N-乙酰葡萄糖胺和D-葡萄糖醛酸交替组成的黏多糖硫酸脂钠盐,是临床大量应用的抗凝血药。研究证明,肝素钠还具有抗炎、抗过敏、抗病毒、抗癌等多种生物学功能。2008年初,欧美各国发生了肝素钠注射液事件,致使81人死亡。随后,美国FDA应用核磁共振方法在肝素钠原料药中定性查出杂质多硫酸软

The standard samples of heparin(HP) and oversulfated chondroitin sulfate(OSCS) were analyzed by 1H NMR.The spectra were assigned.The results showed that the acetyl-methyl peaks of heparin and OSCS have different chemical shift,at δ 2.04 and δ 2.15 respectively.The experimental conditions for quantitative analysis were studied.It was shown that,OSCS content in HP solution can be accurately measured under the following conditions: 25 mg sample in 0.6 mL D2O,0.020%(W/V)TSP,spinning rate 12 Hz,line broadening for EM window functions 1.0,and spectrometer frequency of 500 MHz.

The mechanism of the hydrolysis reaction of diphenylmethane diisocyanate(MDI) in dilute solution was studied by NMR.MDI was dissolved in CDCl3,(CD3)2CO and deuterated diphenyl sulfoxide(DMSO) containing a small quantity of water,respectively,and then were analyzed by 1H NMR and 13C NMR,respectively.The results indicated that the NMR spectrum of MDI in water-containing DMSO solvent was quite different from those in CDCl3 and(CD3)2CO solvents.MDI in DMSO solvent was further studied by 13C-1H heteronuclear multiple-quantum coherence(HMQC),13C-1H heteronuclear multiple-bond correlation(HMBC) and distortionless enhancement by polarization transfer(DEPT 135),respectively,and its corresponding spectra were assigned with the aid of empirical formula.The structures of the products were also confirmed.It was found that MDI reacted rapidly with the water in DMSO,and the isocyanate group transformed into para-/ortho-substituted urea group and para-/ortho-substituted amino group.The reactivity of water with amino group produced from the reaction of isocyanate with water was higher than that of water with isocyanate.The reactivities of water with para-and ortho-substituted amino group were 7.1 and 1.4,respectively.Hence,the effect of water content should be taken into consideration when water-containing DMSO is used as solvent for NMR analysis.

The ~(13)C NMR spectroscopy of MDI was assigned by empirical formula,~1H,DEPT,HMQC and HMBC NMR spectroscopies,and the formula and contents of its isomers were determined.The IR results showed that there were dimer,trimer and urea groups in MDI after long term storage. However,these groups could not be observed by NMR measured in CDCl_3 solvent.

通过在光催化剂掺杂ZnS中加入球笼化合物富勒烯C60,提高了光催化水分解的效率.并采用气相色谱法跟踪反应,发现氢气释放量是未加C60时的4倍多.同时,对该催化反应的机理进行了初步的探讨.

ZnNiS mixed with C_(60) was adopted as photocatalyst to produce H_2 from water. The amount of H_2 evolved was determined by gas chromatography. It was found that the addition of C_(60) increased the amount of H_2, especially at the initial stage of the reaction. Moreover, the mechanism of the photocatalysis reaction of water was discussed.

测定了球碳C60/C70及其衍生物C60Xn/C70Xn的加氢汽油溶液分别与环烷酸钴[Co(naph)2]反应的紫外可见吸收光谱及C60Xn与Co(naph)2反应沉淀物的红外吸收光谱.结果表明:C60/C70及其衍生物均可与Co2+发生配位反应,形成π配体络合物,讨论了可能的反应机理.