On-chip protein isoelectric focusing using a photoimmobilized pH gradient

(J. Sep. Sci. 2014, 37 (21), 3174–3180)
DOI: 10.1002/jssc.201400795
An immobilized pH gradient was directly constructed on the inner wall of a microfluidic chip channel by photo-immobilizing focused carrier ampholytes (CAs) onto the wall. Amixture o…

Contents: J. Sep. Science 21’14

A novel device to concurrently assess leukocyte extravasation and interstitial migration within a defined 3D environment

Lab Chip, 2015, Advance ArticleDOI: 10.1039/C4LC00741G, PaperRaffaella Molteni, Elena Bianchi, Paolo Patete, Monica Fabbri, Guido Baroni, Gabriele Dubini, Ruggero PardiOur device enables qualitative and quantitative assessment in 4D of the interdepende…

A micro-sized bio-solar cell for self-sustaining power generation

Lab Chip, 2014, Accepted ManuscriptDOI: 10.1039/C4LC01069H, PaperHankeun Lee, Seokheun ChoiSelf-sustainable energy sources are essential for a wide array of wireless applications deployed in remote field locations. Due to their self-assembling and self…

Manipulating and quantifying temperature-triggered coalescence with microcentrifugation

Lab Chip, 2015, Advance ArticleDOI: 10.1039/C4LC00773E, PaperHuanhuan Feng, Dmitry Ershov, Thomas Krebs, Karin Schroen, Martien A. Cohen Stuart, Jasper van der Gucht, Joris SprakelCombining microcentrifugation, synchronized high-speed imaging and image…

An experimental study on the numbering-up of microchannels for liquid mixing

Lab Chip, 2015, Advance ArticleDOI: 10.1039/C4LC00987H, PaperYuanhai Su, Guangwen Chen, Eugeny Y. KenigNumbering-up of microchannels was experimentally investigated in a multichannel liquid-liquid micromixer using a model reaction through the blocking …

A Quantitative Look Inside the Body: Minimally Invasive Infrared Analysis in Vivo

Analytical ChemistryDOI: 10.1021/ac5028808

A Quantitative Look Inside the Body: Minimally Invasive Infrared Analysis in Vivo

Analytical ChemistryDOI: 10.1021/ac5028808

Accurate microfluidic sorting of droplets at 30 kHz

Lab Chip, 2014, Accepted ManuscriptDOI: 10.1039/C4LC01194E, CommunicationAdam Sciambi, Abate R AbateFluorescence-activated droplet sorting is an important tool for droplet microfluidic workflows, but published approaches are unable to surpass throughpu…

Unambiguous Characterization of Analytical Markers in Complex, Seized Opiate Samples Using an Enhanced Ion Mobility Trace Detector-Mass Spectrometer

Analytical ChemistryDOI: 10.1021/ac502676d

Use of specific polysaccharide-immobilized monodisperse poly(glycidyl methacrylate) core–silica shell microspheres for affinity purification of lectins

Immobilization of polysaccharides (yeast mannan and gum arabic) on the macroporous poly(glycidyl methacrylate) monodisperse microspheres coated with silica (SiO2)-containing amino groups on the surface was used to prepare affinity sorbents for lectin purification. The efficiency of isolating mannose specific Pisum sativum lectin was demonstrated on sorbent with immobilized yeast mannan and that of galactose specific Glycine hispida lectin on sorbent with immobilized gum arabic. The microspheres with immobilized polysaccharides can be used for selecting an affinity sorbent for purification of other mannose- and galactose-specific lectins. In contrast to yeast mannan, the gum arabic immobilized on the microspheres possesses much narrower specificity and is suitable for purification of only those galactose specific lectins which interact well with l-rhamnose or l-arabinose. The synthesized macroporous particles are capable of immobilizing 50 mg of polysaccharide per 1 g of the matrix, which is 10 times higher than the capacity of epoxy-activated Sepharose 6B. That makes it possible to obtain the same lectin quantity using a column of 10 times smaller volume. Another advantage of novel affinity sorbents comparing corresponding Sepharose gels is the possibility of sorbent drying after use. Copyright © 2014 John Wiley & Sons, Ltd.

Effects of American ginseng on pharmacokinetics of 5-fluorouracil in rats

The pharmacokinetics of 5-fluorouracil (5-FU) in combination with or without American ginseng (seven-consecutive days oral dose) in rats were evaluated using liquid chromatography–electrospray ionization–mass spectrometry (LC-MS). Chromatographic separation was performed on a reverse LC column within a total run time of 6.5 min, which allowed for a relatively quick analysis. The limit of quantification for 5-FU was 15 ng/mL and this method was linear over 15–50,000 ng/mL. This method supported stabilizing determination of the plasma concentration of 5-FU over a period of 24 h. Precision both interday and intraday (coefficient of variation) was within 14% and accuracy (relative error) ranged from −5 to 14%. In view of the observed pharmacokinetic parameters, including maximum concentration, time to maximum concentration, area under the concentration–time curve (AUC), mean residence time, elimination half-life and clearance, our results showed no significant differences in all of the pharmacokinetic parameters between the ginseng co-treated group and 5-FU alone group. Some increase in AUC was observed in 5-FU plus ginseng group; however, the difference did not reach statistical significance compared with 5-FU alone. It appeared that American ginseng administration did not significantly alter the kinetics of 5-FU. More studies are still needed to confirm our results. Copyright © 2014 John Wiley & Sons, Ltd.

Selective and Sensitive Platform for Function-Based Screening of Potentially Harmful Furans

Analytical ChemistryDOI: 10.1021/ac502796x

Innovative Native MS Methodologies for Antibody Drug Conjugate Characterization: High Resolution Native MS and IM-MS for Average DAR and DAR Distribution Assessment

Analytical ChemistryDOI: 10.1021/ac502593n

Quantification of heteroclitin D in rat plasma: validation of an LC/MS/MS method and its application in a preclinical pharmacokinetic study

A rapid, sensitive and specific liquid chromatography tandem mass spectrometry (LC/MS/MS) method was developed and validated for the quantification of heteroclitin D in rat plasma after using gambogic acid as internal standard (IS). Chromatographic separation was done on a Thermo Hypersil GOLD column (30 × 2.1 mm, 3 µm) using a mobile phase consisting of methanol–water–formic acid (80:20:0.1, v/v/v). The mass spectrometer worked with positive electrospray ionization in multiple reaction monitoring mode, using target ions at [M + H]+ m/z 483.3 for heteroclitin D and [M + H]+ m/z 629.3 for the IS. The standard curve was linear (R2 ≥0.995) over the concentration range 9.98–2080 ng/mL and had good back-calculated accuracy and precision. The intra- and interday precision and accuracy determined on three quality control samples (29.94, 166.4 and 1872 ng/mL) were ≤12.8 and –8.9–3.6%, respectively. The extraction recovery was ≥88.2% and the lower limit of quantification was 9.98 ng/mL. The method was successfully applied to evaluate pharmacokinetics of heteroclitin D in Sprague–Dawley rats following a single intravenous bolus injection of 2.0 mg/kg heteroclitin. Copyright © 2014 John Wiley & Sons, Ltd.

Trace quantification of 1-triacontanol in beagle plasma by GC-MS/MS and its application to a pharmacokinetic study

1-Triacontanol (TA), a member of long chain fatty alcohol, has recently been received great attention owing to its antitumor activity. In this study, an accurate, sensitive and selective gas chromatography–tandem mass spectrometry method was developed and validated for the quantification of TA in beagle plasma using 1-octacosanal as the internal standard (IS) for the first time. With temperature programming, chromatographic separation was carried out on an HP-5MS column, using helium as carrier gas and argon as collision gas, both at a flow rate of 1 mL/min. TA was analyzed using positive ion electrospray ionization in multiple-reaction monitoring mode, with the precursor to product ion transitions of m/z 495.6  97.0 and m/z 467.5  97.0 for TA and the IS, respectively. The lower limit of quantitation, linearity, intra- and interday precision, accuracy, stability, extraction recovery and matrix effect of TA were within the acceptable limits. The validated method was successfully applied to a pharmacokinetic study of TA in beagles. Copyright © 2014 John Wiley & Sons, Ltd.

Planar Electrochromatography Using an Electrospun Polymer Nanofiber Layer

Analytical ChemistryDOI: 10.1021/ac503568a

Quantitative Detection of Potassium Ions and Adenosine Triphosphate via a Nanochannel-Based Electrochemical Platform Coupled with G-Quadruplex Aptamers

Analytical ChemistryDOI: 10.1021/ac502752g

Complete Protocol for Slow-Spinning High-Resolution Magic-Angle Spinning NMR Analysis of Fragile Tissues

Analytical ChemistryDOI: 10.1021/ac502792u

The Effect of Glassy Carbon Surface Oxides in Non-Aqueous Voltammetry: The Case of Quinones in Acetonitrile

Analytical ChemistryDOI: 10.1021/ac503176d