An Integrated Theory of Adsorption and Partition Mechanism and Eash Contribution to Solute Retention in Reversed Phase Liquid Chromatography

With the combination of the the stoichiometric displacement model for retention (SDM-R) in reversed phase liquid chromatography (RPLC) and the stoichiometric displacement model for adsorption (SDM-A) in physical chemistry,the total number of moles of the re-solvated methanol of stationary phase side.nr,and that of solute side in the mobile phase,q,corresponding the one mole of the desorbing solute,were separately determined and referred as the characterization parameters of the contributions of the adsorption mechanism and partition mechanism to the solute retention,respectively.A chromatographic system of insulin,using mobile phase consisting of the pseudo-homologue of alcohols(methanol,ethanol and 2-propanol)-water and trifluoroacetic acid was employed.The maximum number of the methanol layers on the stationary phase surface was found to be 10.6,only 3 of which being valid in usual RPLC,traditionally referred as a volume process in partition mechanism.However,it still follows the SDM-R.Both of q and nr of insulin were found not to be zero,indicating that the retention mechanism of insulin is a mixed mode of partition mechanism and adsorption mechanism.When methanol is used as the organic modifier,the ratio of q/nr was 1.13,indicating the contribution to insulin retention due to partition mechanism being a bit greater than that due to adsorption mechanism.A linear relationship between q,or nr and the carbon number of the pseudo-homologue in the mobile phase was also found.As a methodology for investigating the retention mechanism retention and behavior of biopolymers.a homologue of organic solvents as the organic modifier in mobile phase has also been explored.     

高铁酸钾的合成与电化学性能研究

本文主要研究了锂离子电池正极材料高铁酸钾的合成,表征和电化学性质.用次氯酸钾与硝酸铁于碱性介质中反应得到高铁酸钾粗品,重结晶后成纯度大于97%的产品,用XRD和FTIR等方法对高铁酸钾进行表征和分析.初步研究了K2FeO4/Li电池的充放电性能.     

Catalytic Chemosensing Assay for Selective Detection of Methyl Parathion Organophosphate Pesticide

Herein, a catalytic chemosensing assay (CCA), based on a bimetallic complex, [Ru^II(bpy)₂(CN)₂]₂(Cu^II)₂ (bpy=2,2′-bipyridine), is described. This complex integrates a task-specific catalyst (Cu^I-catalyst) and a signaling unit ([Ru^II(bpy)₂(CN)₂]) to specifically hydrolyze methyl parathion, a highly toxic organophosphate (OP) pesticide. The bimetallic complex catalyzed the hydrolysis of the phosphate ester to generate o,o-dimethyl thiophosphate (DTP) anion and 4-nitrophenolate. Intrinsically, 4-nitrophenolate absorbed UV/Vis light at λ_max=400 nm, creating the first level of the chemosensing signal. DTP interacted with the original complex to displace the chromophore, [Ru^II(bpy)₂(CN)₂], which was monitored by spectrofluorometry; this was classified as the second level of chemosensing signal. By integrating both spectroscopic and spectrofluorometric signals with a simple AND logic gate, only methyl parathion was able to provide a positive response. Other aromatic and aliphatic OP pesticides (diazinon, fenthion, meviphos, terbufos, and phosalone) and 4-nitrophenyl acetate provided negative responses. Furthermore, owing to the metal-catalyzed hydrolysis of methyl parathion, the CCA system led to the detoxification of the pesticide. The CCA system also demonstrated its catalytic chemosensing properties in the detection of methyl parathion in real samples, including tap water, river water, and underground water.     

Geminale Azo- und Heteroelement-Funktionen,II: α-Substituierte 2-(4-Chlorphenylazo)-propan-Derivate

The reaction of acetone-4-chlorophenylhydrazone (6) with bromine in the presence of acetamide yields 2-bromo-2-(4-chlorophenylazo)-propane (7) and 2,2-bis(4-chlorophenylazo)propane (8). The unstable heteroallylic bromide7 was subjected without isolation to nucleophilic displacements with a series of heteronucleophiles thereby affording the corresponding 2-(4-chlorophenylazo)-2-propane derivatives9 with the azo- and heteroelement-functions in a geminal position to each other.

Herrn Prof. Dr. Dr. h. c.K. Kratzl mit den besten Wünschen zum 70. Geburtstag gewidmet.     

醋酸水流动相体系中硅胶键合相上生物大分子保留行为的研究

 提出了以醋酸 水作为流动相的体系中 ,在ODS柱上分离生物大分子的反相高效液相色谱 (RPLC)方法。实验结果表明 ,醋酸 水的洗脱能力强于甲醇 水 三氟醋酸体系 ,在一定程度上克服了色谱分离中一些蛋白质的不可逆吸附且具有便于冷冻干燥的优点。用参数Z(1mol溶剂化溶质被溶剂化固定相吸附时从两者接触表面释放出置换剂的摩尔总数 ) ,logI(与 1mol溶质对固定相亲和势有关的常数 )和 j(与 1mol溶剂对固定相亲和势有关的常数 )对 9种蛋白质在此流动相体系中的保留进行了表征。     

A Novel Fluorescent Probe for ATP Detection Based on Synergetic Effect of Aggregation-induced Emission and Counterion Displacement

In this work,a fluorescent probe(TPEBe-I)was developed for adenosine triphosphate(ATP)detection based on the synergetic effect of aggregation-induced emission and counterion displacement.TPEBe-I gave weak emission in aqueous solution due to the heavy-atom effect of counter iodide ion.However,upon the addition of ATP,the new aggregate complex(TPEBe-ATP)was formed between the cationic unit of TPEBe-I and ATP through electrostatic interactions,which not only restricted the intramolecular motion of luminogen but also eliminated the quenching effect of iodide ion.As a result,the fluorescent light-up detection for ATP was successfully achieved.Moreover,TPEBe-I exhibited high selectivity towards ATP and showed a wide linear detection region towards the logarithm of ATP concentration(5—600μmol/L)with a detection limit of 1.0μmol/L,enabling TPEBe-I as a promising probe for ATP quantitative analysis.     

聚二巯化合物正极材料的合成及性质的初步研究

固态电池发展至今，许多比能量高、贮存性能好的新型电池产品不断涌向市场，而目前广泛用于正极材料的大多数物质是层状化合物［１］，如聚乙炔，聚苯胺等化合物，它们贮存能量的方式主要是通过插入化学反应来实现，本工作将合成一种高分子材料——２．５－二巯基－１，３...     

药物间置换相互作用的毛细管电泳-迎头分析法研究

将18-甲基炔诺酮加到人血清白蛋白-酮洛芬平衡溶液中,室温孵育达平衡后应用毛细管电泳-迎头分析法研究了18-甲基炔诺酮和酮洛芬在人血清白蛋白分子上的置换相互作用。一大体积样品虹吸进样至未涂层毛细管(65 cm×50 μm i.d.,有效长度35 cm),进样时间80 s,毛细管两端高度差11 cm,工作电压10 kV,运行缓冲液为67 mmol/L磷酸盐缓冲液(pH 7.4),游离酮洛芬浓度由前沿峰的高度直接测定。当酮洛芬样品溶液中酮洛芬的总浓度分别为100 μmol/L和200 μmol/L时,随着18-甲基炔诺酮加入量的增加(18-甲基炔诺酮的浓度由0增至200 μmol/L),游离酮洛芬的浓度分别从22.4 增至26.4 μmol/L和从82.1增至106.2 μmol/L。由上面的结果可推论:高浓度的18-甲基炔诺酮可将酮洛芬从它的第二类结合位点上置换出来。     

三维树枝状银薄膜的可控生长及其在表面增强拉曼光谱中的应用

通过电流置换反应制备了树枝状银纳米薄膜。在反应过程中通过控制反应时间和硝酸银的浓度,得到了不同形貌、分布和密度的树枝状银薄膜,从而得到了具有不同SERS性能的树枝状银纳米薄膜。选取了具有最佳SERS性能的树枝状银纳米薄膜对罗丹明6G进行了微量检测、再现性检测和稳定性检测,其检测限可达到1×10^-11 mol·L^-1,具有优良的再现性和良好的稳定性。     

A competitive displacement assay with quantum dots as fluorescence resonance energy transfer donors

The unique optoelectronic properties of semiconductor quantum dots (QDs) make them well-suited as fluorescent bioprobes for use in various biological applications. Modification of CdSe/ZnS QDs with biologically relevant molecules provides for multipotent probes that can be used for cellular labeling, bioassays, and localized optical interrogation by means of fluorescence resonance energy transfer (FRET). Herein, we demonstrate the use of red-emitting streptavidin-coated QDs (QD₆₀₅) as donors in FRET to introduce a competitive displacement-based assay for the detection of oligonucleotides. Various QD–DNA bioconjugates featuring 25-mer probe sequences diagnostic of Hsp23 were prepared. The single-stranded oligonucleotide probes were hybridized to dye-labeled (Alexa Fluor 647) reporter sequences, which were provided for a FRET-sensitized emission signal due to proximity of the QD and dye. The dye-labeled sequence was designed to be partially complementary and include base-pair mismatches to facilitate displacement by a more energetically favorable, fully complementary recognition motif embedded within a 98-mer displacer sequence. Overall, this study demonstrates proof-of-concept at the nM level for competitive displacement hybridization assays in vitro by reduction of fluorescence intensity that directly correlates to the presence of oligonucleotides of interest. This work demonstrates an analytical method that could potentially be implemented for monitoring of intracellular gene expression in the future.