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Chemical Research in Chinese Universities 2011年第3期27卷 392-396页

作者： LI Cun-man XIAO Yuan-sheng XUE Xing-ya FENG Jia-tao ZHANG Xiu-li LIANG Xin-miao Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023P.R.China Hebei Research Centre of Analysis and Testing Hebei University of Science and TechnologyShijiazhuang 050018P.R.China

An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was performed with a C18 packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully isolated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleotide compound were simultaneously obtained, each with a purity of 91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, 1D and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products.

关键词： Unstable compound Isolation and purification Preparative high performance liquid chromatography solid-phase extraction Iridoid glucoside

A New Molecularly Imprinted Polymer for solid-phase extraction of Cotinine from Human Urine

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Chinese Chemical Letters 2005年第11期16卷 1503-1506页

作者： Jun YANG Xiao Lan ZHU Ji Bao CAI Qing De SU Yun GAO Liang ZHANG Department of Chemistry University of Science and Technology of China Hefei 230026 Research Center of Tobacco and Health University of Science and Technology of China Hefei 230026

A molecularly imprinted polymer （MIP）, prepared around a cotinine template, has been synthesized. The feasibility of using the polymer for solid-phase extraction （SPE） of cotinine from biological samples has been investigated. The results show that cotinine can be quantitatively retained and eluted from the polymer. Experiments with human urine samples indicate that clean target analyte is obtained for HPLC with UV detection using the protocol.

关键词： Molecularly imprinted polymer solid-phase extraction cotinine urine.

Selective solid-phase extraction of Aloe Emodin from Aloe by Molecularly Imprinted Polymers

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Chemical Research in Chinese Universities 2013年第4期29卷 663-666页

作者： TIAN Ming-lei LEE Yu-ri PARK Dong-wha ROW Kyung-ho College of Chemistry and Environmental Engineering Yangtze University Jingzhou 434023 P R. China Department of Chemical Engineering Regional Innovation Center for Environmental Technology of Thermal Plasma Inha University Ineheon 402-751 Korea

The extraction and separation of aloe emodin were optimized via selective molecularly imprinted solid-phase extraction. Molecularly imprinted polymer was prepared from the functional monomer, methacrylic acid and a mixture of ethanol/dodecanol（90/10, volume ratio） as porogen. It overcomes the common problems of imprin- ting biological polar compounds and shows high selectivity compared favorably with those of non-imprinted polymer and commercially available C18 and silica cartridges in similar aloe emodin tests. Good linearity was obtained be- tween 0.002 and 2.5 mg/mL（r2=0.998） with relative standard deviations below 3.3%.

关键词： Aloe emodin Molecularly imprinted polymer solid-phase extraction High performance liquid chromato- graphy

A solid-phase extraction approach for the identification of pharmaceutical–sludge adsorption mechanisms

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Journal of Pharmaceutical Analysis 2014年第2期4卷 117-124页

作者： Laurence Berthod Gary Roberts Graham A.Mills AstraZeneca Brixham Environmental Laboratory Freshwater QuarryBrixhamDevon TQ5 8BAUK School of Pharmacy and Biomedical Sciences University of PortsmouthPortsmouthHampshirePO1 2DTUK

It is important to understand the adsorption mechanism of chemicals and active pharmaceu-tical ingredients （API） on sewage sludge since wastewater treatment plants are the last barrier before the release of these compounds to the environment. Adsorption models were developed considering mostly hydrophobic API-sludge interaction. They have poor predictive ability, especially with ionisable compounds. This work proposes a solid-phase extraction （SPE） approach to estimate rapidly the API-sludge interaction. Sludge-filled SPE cartridges could not be percolated with API spiked mobile phases so different powders were tested as SPE sludge supports. Polytetrafluoroethylene （PTFE） was selected and tested at different PTFE/sludge ratios under eight different adsorption conditions with three API ionisable compounds. The PTFE/sludge mixtures with 50% or less sludge could be used in SPE mode for API sorption studies with methanol/water liquid phases. The results gave insights into API-sludge interactions. It was found that π-π, hydrogen-bonding and charge-charge interactions were as important as hydrophobicity in the adsorption mechanism of charged APIs on sludge.

关键词： Pharmaceuticals Sewage sludge Adsorption coefficient Binding solid-phase extraction Polytetrafl uoroethylene

Comparison of liquid-liquid extraction-thin layer chromatography with solid-phase extraction-high-performance thin layer chromatography in detection of urinary morphine

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The Journal of Biomedical Research 2011年第5期25卷 362-367页

作者： Ali Ahadi Alireza Partoazar Mohammad Hassan Abedi Khorasgani Seyed Vahid Shetab Boushehri Department of Physiology School of MedicineTehran University of Medical Sciences Department of Pharmacology School of MedicineTehran University of Medical Sciences Legal Medicine Organization of Iran Iran Department of Medical Nanotechnology School of MedicineTehran University of Medical Sciences

Liquid-liquid extraction-thin layer chromatography （LLE-TLC） has been a common and routine combined method for detection of drugs in biological materials. solid-phase extraction （SPE） is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography （HPTLC） has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, ＇were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories.

关键词： morphine detection liquid-liquid extraction thin-layer chromatography solid-phase extraction highperformance thin layer chromatography

solid-phase extraction of trans-resveratrol by molecularly imprinted polymers with bi-functional monomers

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Solid-phase extraction of trans-resveratrol by molecularly i...

Separation and Enrichment of Melamine in Feed by a New Molecularly Imprinted solid-phase extraction Column

甘肃省化学会二十六届年会暨第八届中学化学教学经验交流会

作者： Chuande Zhao~1,Rui Chen~1,Xiaoman Jiang~1,Linyuan Guo~1,Haixia Zhang~(1,2) 1 Department of Chemistry,Lanzhou University,Lanzhou 730000,China, 2 State Key Laboratory of Applied Organic Chemistry,Lanzhou University,Lanzhou 730000,China

With methacrylic acid andβ-cyclodextrin acting functional monomers,trans-resveratrol molecularly imprinted polymers were synthesized in this *** with each other,the molecularly imprinted polymer coming from two above mentioned functional monomers has higher adsorption capacity and higher selective factor than that one produced only by methacrylic *** kinds of molecularly imprinted polymers are superior to their corresponding non-imprinted polymers in adsorption capacity and *** bi-functional monomers molecularly imprinted polymer(1) has been used as the packing material of solid phase extraction to concentrate trans-resveratrol in wine and Chinese liquor *** analytical method to determine trans-resveratrol in wine and Chinese liquor has been *** limit of detection for trans-resveratrol was 0.001μg mL.

关键词： Molecularly imprinted polymers Methacrylic acid β-cyclodextrin Trans-resveratrol solid-phase extraction High performance liquid chromatography

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Animal Husbandry and Feed Science 2014年第1期6卷 10-13页

作者： Huang Huabin Zhuang Zhixia Zhou Yanli Zhao Li Wang Xiaoru Xiamen Huaxia Vocational College College of Chemistry and Chemical Engineering Xiamen University

[ Objective] The research aimed to develop a new molecular imprinting solid-phase extraction column for the separation and enrichment of melamine in feed. [ Method] The molecular imprinting polymer of melamine was prepared by mass polymerization method. This polymer was used as filler to prepare molecular imprinting polymer solid-phase extraction（MIP-SPE） column of melamine. The solid-phase extraction conditions were optimized and melamine content in concentrated solution was determined by using HPLC. [ Result] Melamine eould be separated selectively from feed and enriehed by self-made MIP-SPE column. It could wipe off complex matrix from feed and the addition recovery rate was 95%. The contrast experiment between MIP-SPE column and NMIP-SPE （ non-imprinted polymer- solid phase extraction） column showed that the extraction efficiency of the former was obviously higher than the latter. [ Conclusion] The home-made MIP- SPE column could be used to separate and enrich melamine in feed efficiently, with a broad application prospect.

关键词： Molecular imprinting solid-phase extraction Feed Melamine

Analysis of trace mercury in water by solid phase extraction using dithizone modified nanometer titanium dioxide and cold vapor atomic absorption spectrometry

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Rare Metals 2007年第6期26卷 541-546页

作者： MA Xiaoguo HUANG Bei CHENG Meiqing Faculty of Environmental Science and Engineering Guangdong University of Technology Guangzhou 510090 China Department of Chemical Engineering Maoming University Maoming 525000 China

A new method for analysis of trace mercury in water samples was developed, based on the combination of preconcentration/separation using dithizone-modified nanometer titanium dioxide （TiO2） as a solid phase extractant and determination by cold vapor atomic adsorption spectrometry （CVAAS）. Dithizone was dissolved with alcohol and loaded on the surface of nano-sized TiO2 powders by stirring. The static adsorption behavior of Hg^2＋on the dithizone-modified nanoparficles was investigated in detail. It was found that excellent adsorption ratio for Hg^2＋ could be obtained in the pH range of 7-8 with an oscillation time of 15 rain, and a 5 mL of 3.5 mol·L^-1 HCI solution could quantitatively elute Hg^2＋ from nanometer TiO2 powder. Common coexisting ions caused no obvious influence on the determination of mercury. The mechanisms for the adsorption and desorption were discussed. The detection limit （30） for Hg^2＋ was calculated to be 5 ng·L^-1. The proposed method was applied to the determination of Hg^2＋ in a mineral water sample and a Zhujiang River water sample. By the standard addition method, the average recoveries were found to be 94.4%-108.3% with RSD （n = 5） of 2.9%-3.5%.

关键词： analytical chemistry mercury solid-phase extraction TiO2 nanoparticle cold vapor atomic adsorption spectrometry (CVAAS)

Molecular Imprinted solid-phase extraction of Huperzine A from Huperzia serrata

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Molecular Imprinted Solid-phase Extraction of Huperzine A fr...

Determination of 4-Nitrophenol in water samples by Fluorescence Quenching Combined with Molecularly Imprinted solid-phase extraction

第五届全国化学生物学学术会议

作者： Wang GuoSong Cao QiuE Zhu XiuFang Ding ZhongTao~* Key Laboratory of Medicinal Chemistry for Nature Resource,Ministry of Education,School of Chemical Science and Technology,Yunnan University,Kunming 650091,Yunnan,P.R.China

＜正＞Huperzine A,a lycopodium alkaloid,is recognized to be a promising lead structure in the therapy of senile dementia and cognitive impairment in Alzheimer’s *** this work,some molecularly imprinted polymers（MIPs）of huperzine A were synthesized with methacrylic acid, acrylamide,2-vinylpyridine,or 4-vinylpyridine as functional monomer,***

关键词： Huperzia serrata imprinted polymers Huperzine A solid-phase extraction

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Determination of 4-Nitrophenol in water samples by Fluoresce...