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Chenning Zhang, Caibin Qin, Guangyi Yang, Fadia Boughaba, Yue He, Weidong Ma, Yonghong Zhang, Song Gao
Maoecrystal A (MC-A) is an ent-kaurane-type diterpene isolated from Rabdosia eriocalyx (Dunn) Hara. MC-A has been reported to show different types of pharmacological activities, including anticancer, anti-inflammatory and bacteriostatic functions. However, bioanalysis of MC-A has not been reported. The purpose of this study is to develop an UPLC-MS/MS method to quantify MC-A in plasma and determine its pharmacokinetic properties using an animal model. The separation was performed using a Waters HSS T3 column (50 mm × 2...
April 10, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Anna Kjerstine Rosenmai, Johan Lundqvist, Théo le Godec, Åsa Ohlsson, Rikard Tröger, Björn Hellman, Agneta Oskarsson
The presence of chemical pollutants in sources of drinking water is a key environmental problem threatening public health. Efficient removal of pollutants in drinking water treatment plants (DWTPs) is needed as well as methods for assessment of the total impact of all present chemicals on water quality. In the present study we have analyzed the bioactivity of water samples from source to tap, including effects of various water treatments in a DWTP, using a battery of cell-based bioassays, covering health-relevant endpoints...
April 6, 2018: Water Research
Yu-Wen Su, Wei Wang
Surface plasmon resonance (SPR) has become a well-recognized label-free technique for measuring the binding kinetics between biomolecules since the invention of the first SPR-based immunosensor in 1980s. The most popular and traditional format for SPR analysis is to monitor the real-time optical signals when a solution containing ligand molecules is flowing over a sensor substrate functionalized with purified receptor molecules. In recent years, rapid development of several kinds of SPR imaging techniques have allowed for mapping the dynamic distribution of local mass density within single living cells with high spatial and temporal resolutions and reliable sensitivity...
April 12, 2018: Analytical and Bioanalytical Chemistry
Kenichiro Todoroki, Tomohiro Yamada, Hajime Mizuno, Toshimasa Toyo'oka
The increase in the use of therapeutic monoclonal antibodies (mAbs) and antibody-drug conjugates (ADCs) has made the detailed bioanalysis of these drugs essential not only for planning optimal therapeutic programs for clinical practice, but also for evaluating the biological equivalencies in the development of other biosimilars. The ligand binding assays that are widely in use now are being replaced rapidly by the highly accurate, sensitive, and selective analytical method using a mass spectrometer. This review will discuss the progress in and challenges observed during the development of a mass spectrometry-based bioanalytical method for therapeutic mAbs and ADCs...
2018: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
Yang Zhao, Lu Tan, Xiaoshan Gao, Guifen Jie, Tingyu Huang
Herein, we successfully devised a novel photoelectrochemical (PEC) platform for ultrasensitive detection of adenosine by target-triggering cascade multiple cycle amplification based on the silver nanoparticles-assisted ion-exchange reaction with CdTe quantum dots (QDs). In the presence of target adenosine, DNA s1 is released from the aptamer and then hybridizes with hairpin DNA (HP1), which could initiate the cycling cleavage process under the reaction of nicking endonuclease. Then the product (DNA b) of cycle I could act as the "DNA trigger" of cycle II to further generate a large number of DNA s1, which again go back to cycle I, thus a cascade multiple DNA cycle amplification was carried out to produce abundant DNA c...
March 30, 2018: Biosensors & Bioelectronics
Jing Zhu, Haiying Gan, Jie Wu, Huangxian Ju
A bipedal molecular machine powered surface programmatic chain reaction was designed for electrochemical signal amplification and highly sensitive electrochemical detection of protein. The bipedal molecular machine was built through aptamer-target specific recognition for the binding of one target protein with two DNA probes, which hybridized with surface-tethered hairpin DNA 1 (H1) via proximity effect to expose prelocked toehold domain of H1 for the hybridization of ferrocene-labeled hairpin DNA 2 (H2-Fc)...
April 4, 2018: Analytical Chemistry
Ling Zhang, Yuan-Cheng Zhu, Yan Yu Liang, Wei-Wei Zhao, Jing-Juan Xu, Hong-Yuan Chen
This work reports the synthesis, characterization and application of bifunctional semiconducting CuO nanotubes (NTs) elec-trode for innovative synergized cathodic photoelectrochemical (PEC) enzymatic bioanalysis. Specifically, CuO NTs electrode was fabricated by surface oxidation of the copper foil in an alkaline aqueous solution with (NH4)2S2O8 and then annealed in air at 200 ºC. After the subsequent coupling with the model enzyme of xanthine oxidase (XOD), the resulted photocathodic enzyme biosensor exhibited good analytical performance of rapid response, high stability, and good sensitivity...
April 2, 2018: Analytical Chemistry
Michael W Linscheid
To understand biological processes, not only reliable identification, but quantification of constituents in biological processes play a pivotal role. This is especially true for the proteome: protein quantification must follow protein identification, since sometimes minute changes in abundance tell the real tale. To obtain quantitative data, many sophisticated strategies using electrospray and MALDI mass spectrometry (MS) have been developed in recent years. All of them have advantages and limitations. Several years ago, we started to work on strategies, which are principally capable to overcome some of these limits...
March 30, 2018: Mass Spectrometry Reviews
Xing-Pei Liu, Xing-Li Xie, Yu-Ping Wei, Chang-Jie Mao, Jing-Shuai Chen, He-Lin Niu, Ji-Ming Song, Bao-Kang Jin
A film of perovskite-type LaFeO3 nanoparticles (NPs) was deposited on fluorine-doped tin oxide (FTO) conducting glass via dipping-lifting and calcination. Scanning electron microscopy shows that the NPs are evenly distributed on the surface of the glass. The modified glass was further coated with antibody against human interleukin 6 (IL-6) to result in a photoelectrochemical immunosensor for IL-6. The well-established photoelectrochemical immunoassay has a linear current response in the range of 0.1 pg·mL-1 to 0...
December 14, 2017: Mikrochimica Acta
Chuan Shi, Shalom Goldberg, Tricia Lin, Vadim Y Dudkin, Wayne C Widdison, Luke Harris, Sharon D Wilhelm, Yazen Jmeian, Darryl Davis, Karyn O'Neil, Naidong Weng, Wenying Jian
Bioanalysis of antibody-drug conjugates (ADCs) is challenging due to the complex, heterogeneous nature of their structures and their complicated catabolism. To fully describe the pharmacokinetics (PK) of an ADC, several analytes are commonly quantified, including total antibody, conjugate, and payload. Among them, conjugate is the most challenging to measure because it requires detection of both small and large molecules as one entity. Existing approaches to quantify the conjugated species of ADCs involve a ligand binding assay (LBA) for conjugated antibody or hybrid LBA/liquid chromatography-tandem mass spectrometry (LC-MS/MS) for quantitation of conjugated drug...
March 28, 2018: Analytical Chemistry
Lu Han, Ying Li, Aiping Fan
Peroxidase is a commonly used catalyst in luminol-H2 O2 chemiluminescence (CL) reactions. Natural peroxidase has a sophisticated separation process, short shelf life and unstable activity, therefore it is important to develop peroxidases that have both high catalytic activity and good stability as alternatives to the natural enzyme. Gold nanoclusters (Au NCs) are an alternative peroxidase with catalytic activity in the luminol-H2 O2 CL reaction. In the present study, ethanediamine was modified on the surface of Au NCs forming cationic Au NCs...
March 25, 2018: Luminescence: the Journal of Biological and Chemical Luminescence
Aimin Tan, John C Fanaras
LC-MS/MS has been the dominant analytical technology for quantitative bioanalysis of drugs and metabolites for more than two decades. Despite this, a very fundamental question like how much separation is required for LC-MS/MS quantitative bioanalysis of drugs and metabolites has not been adequately addressed. Some think that no or only very limited separation is necessary thanks to the unparalleled selectivity offered by tandem mass spectrometry. Others think that the more separation, the better, because of the potential detrimental impact of matrix effect (ion suppression or enhancement)...
March 14, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Shurui Wang, Wenwen Tu, Zhihui Dai
An innovative and ultrasensitive photoelectrochemical bioanalysis strategy was designed, which provided a promising method for the assay of tumor markers. The BiOI/g-C3N4 composite acted as photoelectrochemical biosensing substrate for significant signal enhancement, and CuS NPs were introduced to label signal antibodies to amplify the signal variation.
March 20, 2018: Analyst
Beatriz Díez-Buitrago, Nerea Briz, Luis M Liz-Marzán, Valeri Pavlov
Enzymes are pivotal elements in bioanalysis due to their specificity and extremely high catalytic activity. The sensitivity of bioanalytical assays depends mainly on the capacity of an observer to detect the product(s) of a biocatalytic reaction. Both natural and artificial compounds have been traditionally used to evaluate enzymatic activities. The drawbacks of chromogenic and fluorogenic organic enzymatic substrates are their high cost and low stability, resulting in high background signals. We review here state of the art assays in the detection of enzymatic activities using recent advances in nanoscience...
March 19, 2018: Analyst
Ahmed Ma'mun, Mohamed K Abd El-Rahman, Mohamed Abd El-Kawy
In recent years, the whole field of ion-selective electrodes(ISEs) in pharmaceutical sciences has expanded far beyond its original roots. The diverse range of opportunities offered by ISEs was broadly used in a number of pharmaceutical applications, with topics presented ranging from bioanalysis of drugs and metabolites, to protein binding studies, green analytical chemistry, impurity profiling, and drug dissolution in biorelevant media. Inspired from these advances and with the aim of extending the functional capabilities of ISEs, the primary focus of the present paper is the utilization of ISE as a tool in personalized medicine...
February 7, 2018: Journal of Pharmaceutical and Biomedical Analysis
Alberto Gil de la Fuente, Joanna Godzien, Mariano Fernández López, Francisco J Rupérez, Coral Barbas, Abraham Otero
CEU Mass Mediator (CMM) is an on-line tool for aiding researchers when performing metabolite annotation. Its database is comprised of 279,318 real compounds integrated from several metabolomic databases including Human Metabolome Database (HMDB), KEGG and LipidMaps and 672,042 simulated compounds from MINE. In addition, CMM scores the annotations which matched the query parameters using 122 rules based on expert knowledge. This knowledge, obtained from the Centre for Metabolomics and Bioanalysis (CEMBIO) and from a literature review, enables CMM expert system to automatically extract evidence to support or refute the annotations by checking relationships among them...
February 23, 2018: Journal of Pharmaceutical and Biomedical Analysis
Michał Romański, Anna Zacharzewska, Artur Teżyk, Franciszek K Główka
BACKGROUND AND OBJECTIVES: Treosulfan is a prodrug applied in the treatment of ovarian cancer and conditioning prior to stem cell transplantation. So far, the bioanalysis of treosulfan in either whole blood or red blood cells (RBC) has not been carried out. In this work, the RBC/plasma partition coefficient (Ke/p ) of treosulfan and its active monoepoxide was determined for the first time. METHODS: Male and female 10-week-old Wistar rats (n = 6/6) received an intraperitoneal injection of treosulfan at the dose of 500 mg/kg body weight...
March 14, 2018: European Journal of Drug Metabolism and Pharmacokinetics
Zhi-Mei Li, Xiao Zhang, Ru-Ping Liang, Xiang-Juan Zheng, Jian-Ding Qiu
In this work, a newly developed surface plasma resonance (SPR) system for the sensitive detection of M.SssI activity has been designed based on double signal amplification with DNA chain cyclic reactions and AuNPs. In the absence of M.SssI, hairpin DNA 1 (HP1) can be cleaved into s1 fragments catalyzed by HpaII. The s1 fragments can then trigger a recycling process of hairpin DNA 2 (HP2) hybridization and subsequently release massive s2 and s3 in the solution of Nt.AlwI and HPII. AuNPs-DNA can be captured on gold film by the released s2 and s3 to produce a strong SPR signal...
August 3, 2018: Analytica Chimica Acta
Xiao-Mei Shi, Li-Ping Mei, Qian Wang, Wei-Wei Zhao, Jing-Juan Xu, Hong-Yuan Chen
We report herein the energy transfer (ET) between semiconducting polymer dots (Pdots) and gold nanoparticles (Au NPs) in a photoelectrochemical (PEC) system and its feasibility for cathodic bioanalysis application. Specifically, COOH-capped Pdots were first fabricated and then assembled onto the indium-tin oxide (ITO) surface, followed by the modification of single-strand (ss) DNA probe (pDNA). After the DNA hybridization with the Au NP-tethered complementary ssDNA (Au NP-tDNA), the Au NPs were brought into the close proximity of Pdots...
March 13, 2018: Analytical Chemistry
Xiao Ling, Yuqiang Xiang, Feilong Chen, Qingfa Tang, Wei Zhang, Xiaomei Tan
Intestinal condition plays an important role in drug absorption and metabolism, thus the effects of varied gastrointestinal diseases such as infectious diarrhea on the intestinal function are crucial for drug absorption. However, due to the lack of suitable models, the differences of absorption and metabolism of drugs between the diarrheal and normal intestines are rarely reported. Thus, in this study, Escherichia coli diarrhea model was induced in mini-pigs and single-pass intestinal perfusion and intestinal mucosal enzyme metabolism experiments were conducted...
March 3, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
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