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INVESTIGATion ON SEPARATion OF INORGANIC ANionS BY REVERSED-PHASE ion-pair LIQUID CHROMATOGRAPHY

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Chinese Science Bulletin 1991年第17期36卷 1444-1447页

作者：邹汉法李喜来张玉奎卢佩章 Dalian Institute of Chemical Physics Academia Sinica Dalian Chromatographic R. & D. Center of China Dalian 116011 PRC

Ⅰ. INTRODUCTionReversed-phase ion-pair liquid chromatography is widely used in the separation of ionized organic compounds. In recent years, the separation of inorganic ions by the reversedphase ion-pair liquid chrom... 详细信息

关键词： reversed-phase ion-pair chromatography inorganic anions direct UV detection.

An ion-pair HPLC Method for Simultaneous Determination of Exogenous Phosphocreatine and Its Metabolite Creatine and Related ATP in Rabbit Plasma and RBC: Application to a Pharmacokinetic Study

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Journal of Analytical Sciences, Methods and Instrumentation 2013年第3期3卷 17-23页

作者： Li Lv Heng Xi Guozhu Han Department of Pharmacology College of Pharmacy Dalian Medical University Dalian China.

A specific, precise and accurate ion-pair HPLC-UV method has been developed and validated for simultaneous determination of phosphocreatine (PCr), and its metabolite creatine (Cr) as well as related ATP in plasma and red blood cell (RBC) of rabbits. After addition of TMP as IS, the samples were deproteinized with 6% PCA. The analytes were separated on a Kromasil C18 column using a tertiary gradient mobile phase composed of buffer A (0.2% KH2PO4 + 0.08% tetrabutyl ammonium hydrogen sulphate, pH 3.0), buffer B (buffer A adjusted to pH 7.5 with 1 mol/L NaOH) and MeOH. Detection wavelengths were set at 210 nm for PCr and Cr and 260 nm for ATP and TMP. Some blank samples were initially run for baseline subtraction. The linear detection responses were obtained for PCr concentration over a range of 10 - 7500 mg/ml (plasma) and 5 - 2500 mg/ml (RBC) and for both Cr and ATP concentrations of 10 - 1500 mg/ml (plasma) and 5 - 750 mg/ml (RBC) (r > 0.99). The QC samples of 3 analytes showed intra-day and inter-day precisions (RSD) of - 107%. The method was successfully used to simultaneously determine plasma and RBC concentrations of the 3 analytes and to study pharmacokinetics after iv administration of PCr to rabbits.

关键词： ion-pair HPLC Phosphocreatine Creatine ATP Plasma RBC Pharmacokinetics Rabbit

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液相色谱-质谱法对奶粉中唾液酸含量的测定

分析测试学报 2008年第S1期27卷 193-194页

作者：栗晖金一宝刘红霞于治国高春梅蒋宇扬清华大学深圳研究生院广东省化学生物学重点实验室广东深圳518055 沈阳药科大学辽宁沈阳110016 清华大学医学院北京100084

A simple and sensitive ion-paring HPLC-MS/MS method with negative ion mode has been developed and validated for the quantification of SA in *** separation was performed on C18 column with a mobile phase consisting of 4 mmol/L tetrabutylammonium hydroxide-methanol at a flow rate of 0.2 mL/min under the gradient *** retention time of SA was 6.1 ***-quadrupole MS/MS detection was operated in negative mode by monitoring the transition of m/z 308.1>87.1 for *** results indicated that the lower limit of quantification was 0.060 mg/L and the assay showed a linear range of 0.1-100 mg/L and gave a correlation coefficient(r) of *** relative standard deviations were less than 10% at all tested concentration *** method has been successfully applied to the analysis of SA in milk,milk powder and breast milk.

关键词： sialic acid ion-pair HPLC-MS/MS

Self-assembly Induced by Complexation of Diblock Copolyelectrolytes and Oppositely Charged Homopolymers

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Chinese Journal of Polymer Science 2024年第9期42卷 1321-1332,I0006页

作者： Ling Zhao Zhi-Yuan Yin Jia-Di Jiang Er-Qiang Chen Shuang Yang Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Mater Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

We investigate the solution self-assembly of a mixture of positively charged homopolymers and AB diblock copolymers,in which the A blocks are negatively charged,and the B blocks are *** electrostatic complexation between oppositely charged polymers drives the formation of many ordered *** microstructures and phase diagrams are calculated using self-consistent field theory(SCFT)based on an ion-pair model with an equilibrium constant K to characterize the strength of binding between positively and negatively charged *** effects of the charge ratio,representing the ratio of charges from the homopolymer over all charges from polymers in the system,on the ordered structure are systematically studied,both for hydrophobic and hydrophilic A *** charge ratio plays an important role in determining the phase boundaries in the phase diagram of salt concentration versus polymer *** also provide information about the varying tendency of the domain spacing and core size of the spherical phase when the charge ratio is changed,and the results are in good agreement with *** studies provide a deep understanding of the self-assembled microstructures of oppositely charged diblock copolymer-homopolymer systems.

关键词： Self-assembly Polyelectrolyte complexation Self-consistent field theory ion-pair

Spectrophotometric and spectrofluorimetric methods for the determination of ropinirole content in pharmaceutical dosage forms

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Journal of Chinese Pharmaceutical Sciences 2016年第12期25卷 876-881页

作者： Effat Souri Milad Torabadi Maliheh Barazandeh Tehrani Department of Medicinal Chemistry Faculty of Pharmacy and Drug Design and Development Research CenterTehran University of Medical Sciences

Two simple and rapid spectrofluorimetric and spectrophotometric methods were described for the determination of ropinirole hydrochloride content in pharmaceutical dosage forms. Both methods are based on the reaction of ropinirole hydrochloride and eosin Y in aqueous medium at p H 4.0. Quenching of the fluorescence intensity of eosin Y at 540 nm upon excitation at 350 nm was used for the determination of ropinirole hydrochloride levels after ion-pair complex formation. Also, the absorbance increase of eosin Y at 546 nm after ion-pair complex formation was used for spectrophotometric measurements. Both methods showed linear relationships between the fluorescence quenching or absorbance increase and ropinirole concentration in the range of 6–150 μg/m L and 50–500 μg/m L for spectrofluorimetric and spectrophotometric methods, respectively. As no organic solvents were used in these two methods, they could be categorized as green analytical methods. Both methods were accurate(Errorion of ropinirole hydrochloride content in pharmaceutical dosage forms without any significant interference from associated impurities.

关键词： Ropinirole Spectrophotometry Spectrofluorimetry Eosin Y ion-pair complex

CdI<sub>2</sub>Extraction with 18-Crown-6 Ether into Various Diluents: Classification of Extracted Cd(II) Complex ions Based on the HSAB Principle

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American Journal of Analytical Chemistry 2018年第11期9卷 560-579页

作者： Yoshihiro Kudo Yamato Ishikawa Hikaru Ichikawa Graduate School of Science Chiba University Chiba Japan Department of Chemistry Faculty of Science Chiba University Chiba Japan

CdI2 in water was extracted with 18-crown-6 ether (L) into 10 diluents at 298 K. The following equilibrium constants were determined or evaluated: some extraction constants (Kex/mol-3·dm9 & Kex,ip/mol-2·dm6 for CdLI2, Kex±/mol-2·dm6 for CdLI+ with I-, & Kex2±/mol-1·dm3 for CdL2+ with 2I-), conditional distribution constants (KD,I for I-, KD,CdLI for CdLI+, & KD,CdL for CdL2+) between the two phases, and an ion-pair formation constant (K1,org/mol-1·dm3) for CdLI+ and that (K2,org/mol-1·dm3) for CdLI2 in the organic (org) phases. Using the K1,org and K2,org values, acidities of the complex ions, CdL2+ and CdLA+ (A- = I-, Br-, & Cl-), in the 11 diluents were classified by applying the HSAB rule. Especially, the CdLA+ ions were classified as the soft acids in 9 diluents. Also, molar volumes (Vj/cm3·mol-1) of j = CdLI2 and CdL2+ were determined with the regular-solution-theory plot of logKex,ip vs. logKD,L and its pseudo-plot of logKD,CdL, respectively. Here, KD,L denotes the distribution constant of L between the two phases. So, sizes among CdLA2 and CdL2+ were compared by using the Vj values. Additionally, some distribution equilibrium potentials (dep/V) between the water and org bulk phases were topically calculated from an equation of KD,I with KSD,I, where the symbol KSD,I shows a standard distribution constant of I- at dep = 0 V for a given diluent.

关键词： ion-pair Formation Constants HSAB Acidity Molar Volume Conditional Distribution Constants Distribution Equilibrium Potentials Cadmium Iodide 18-Crown-6 Ether

Distribution of Ag(I), Li(I)-Cs(I) Picrates, and Na(I) Tetraphenylborate with Differences in Phase Volume between Water and Diluents

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American Journal of Analytical Chemistry 2020年第1期11卷 25-46页

作者： Satoshi Ikeda Saya Morioka Yoshihiro Kudo Graduate School of Science and Engineering Chiba University Chiba Japan

ionic strength conditions in distribution experiments with single ions are very important for evaluating their distribution properties. Distribution experiments of picrates (MPic) with M = Ag(I) and Li(I)-Cs(I) into o-dichlorobenzene (oDCBz) were performed at 298 K by changing volume ratios (Vorg/V) between water and oDCBz phases, where “org” shows an organic phase. Simultaneously, an analytic equation with the Vorg/V variation was derived in order to analyze such distribution systems. Additionally, the AgPic distribution into nitrobenzene (NB), dichloromethane, and 1,2-dichloroethene (DCE) and the NaB(C6H5) 4 (=NaBPh4) one into NB and DCE were studied at 298 K under the conditions of various Vorg/V values. So, extraction constants (Kex) for MPic into the org phases, their ion-pair formation constants (KMA,org) for MA = MPic in the org ones, and standard distribution constants () for the M(I) transfers between the water and org bulk phases with M = Ag and Li-Cs were determined at the distribution equilibrium potential (dep) of zero V between the bulk phases and also the Kex (NaA), KNaA,org, and values were done at A-=BPh-4. Here, the symbols Kex, KMA,org, and or were defined as [MA] org/[M+][A-], [MA] org/[M+]org [A-]org, and [M+]org/[M+] or [A-]org/[A-] at dep = 0, respectively. Especially, the ionic strength dependences of Kex and KMPic,org were examined at M = Li(I)-K(I) and org = oDCBz. From above, the conditional distribution constants, KD,BPh4 and KD,Cs, were classified by checking the experimental conditions of the I, Iorg, and dep values.

关键词： Standard Distribution Constants Volume Ratios Distribution Equilibrium Potentials ionic Strength Dependence Extraction Constant ion-pair Formation Constant o-Dichlorobenzene

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液相色谱-质谱法对奶粉中唾液酸含量的测定

液相色谱-质谱法对奶粉中唾液酸含量的测定