Online coupled

The previous model setup included an identical horizontal resolution for ocean and atmosphere, and online coupling was implemented in the ECHAM submodel with an exchange rate of 3 hours. In the current model setup atmosphere and ocean are coupled online using the Ocean-Atmosphere-Sea Ice-Soil (OASIS) coupler [Valcke et al (2004)] with a coupling time step of one day. OASIS passes boundary condi-... 

A newer addition is in-tube SPME that makes use of an open capillary device and can be coupled online with GC, HPLC, or LC/MS. All these techniques and their utilization in pharmaceutical and biomedical analysis were recently reviewed by Kataoka.45 Available liquid stationary fiber coatings for SPME include polydimethylsiloxane (PDMS) and polyacrylate (PA) for extracting nonpolar and polar compounds, respectively. Also in use for semipolar compounds are the co-polymeric PDMS-DVB, Carboxen (CB)-PDMS, Carbowax (CW)-DVB, and Carbowax-templated resin (CW-TPR). A few examples of in-tube SPME extractions from biological matrices are shown in Table 1.19 and drawn from Li and coworkers.166... 

For reproducible expression analysis and protein quantification MS methods based on isotopic labeling are available. They were designed in conjunction with two or more dimensional chromatographic peptide separation coupled online to MS and require advanced bioinformatics input to analyze the complex data sets in a reasonable time frame. This is also true for the alternative fluorescence-based technology of differential gel electrophoresis (DIGE Fig. 10.6) with tailor-made software which allows statistical validation of multiple data sets. 

Javerfalk, E. M., Amini, A., Westerlund, D., and Andren, P. E. (1998). Chiral separation of local anesthetics by a capillary electrophoresls/partlal filling technique coupled online to microelectrospray mass spectrometry. /. Mass Spectrom. 33, 183 — 186. 

T. Schenk, G. J. Breel, P. Koevoets, S. van den Berg, A. C. Hogenboom, H. Irth, U. R. Tjaden, J. van der Greef Screening of natural products extracts for the presence of phosphodiesterase inhibitors using liquid chromatography coupled online to parallel biochemical detection and chemical characterization, f Biomol Screen 2003, 8, 421-429. 

EM Javerfalk, A Amini, D Westerlund, PE Andren. Chiral separation of local anaesthetics by a capillary electrophoresis/partial-filling technique coupled online to micro-electrospray mass spectrometry. J Mass Spectrom 33 183-186, 1998. 

There are only few references on odd-numbered lactones in the literature. The first reports on the natural occurrence of y-nonalactone and y-undecalactone are known from the early flavour literature [28-30], long before sophisticated analytical techniques, such as enantio-cGC-MS, became available. These data have to be reevaluated, should the situation arise. Worner et al. [31] provided the first report on y-nonalactone among the volatile constituents of Artemisia vulgaris L. herb, revealing an amount between 1 andlO pg/kg and an enantiomeric distribution of (i )-y-nonalactone to (S)-y-nonalactone of 34 66 using en-antio-MDGC, coupled online with MS. 

IRMS has become more and more important in food authenticity assessment, since cGC, coupled online via a suitable combustion/pyrolysis interface with IRMS has been realised. The substances eluted from the cGC column are converted into the corresponding gas (carbon dioxide, nitrogen, hydrogen and car-... 

The latest development is MDGC coupled online with IRMS. This coupling technique combines the advantages of both highly sophisticated techniques, to achieve the utmost accuracy of IRMS measurements [54]. 

Microdialysis to monitor the chemistry of extracellular space in human tissue is a challenging technique that has been applied in the neurosciences to measure neurochemical composition in vivo.104 Microdialysis coupled online with in-tube solid phase extraction (SPE) and ICP-MS has been developed by Sun et al.105 for the in vivo determination of several trace metals in order to study the transfer kinetics of trace elements in brain extracellular fluid. 

RA Williams, R Macrae, MJ Shepherd. Non-aqueous size-exclusion chromatography coupled online to reversed phase high performance liquid chromatography. Interface development and applications to the analysis of low-molecular weight contaminants andadditives in foods. J Chromatogr 477 315-325, 1989. 

Solid-phase extraction could be coupled online with HPLC. This is becoming increasingly important, because it makes it possible to handle all the situations in which large series of samples have to be analyzed routinely, and therefore rapid, (semi-) automatic, and unattended analysis is an aspect of major concern. Moreover, sensitive trace level determination requires the analysis of total samples or sample extracts rather than aliquots, under conditions in which analyte losses, due to evaporation or irreversible sorption to the vessels walls, and contamination, caused by the solvent or reagents used, laboratory air, and/or sample manipulation in general, must be rigorously minimized (45,46). 

Extraction in liquid/liquid segmented flow has been developed. A continuous-flow extraction system coupled online with an RP-HPLC with C-l 8 and a UV detector was used to study the extraction of fenthion and azinphos methyl in water (82). 

Deng, H., and Van Berkel, G. J. (1999). A thin-layer electrochemical flow cell coupled online with electrospray-mass spectrometry for the study of biological redox reactions. 

An ESI mass spectrometer coupled online to a microreactor was used to intercept the catalytically active cationic intermediates of the Ziegler-Natta polymerization of ethylene with the homogeneous catalyst system [Cp2Zr(Me)Cl]-MAO (MAO = methylaluminoxane). For the first time these intermediates were studied directly in the solution and their catalytic activity proved.60... 

Bouzas et al. [95] developed a quantitation method for the determination of drugs of abuse (opiates, amphetamine and derivatives, cocaine, methadone and metabolites) in serum by using online extraction coupled to LC-MS/MS. The online extraction procedure described consists of an extraction column and an analytical column, which were coupled online. A PPT procedure was performed with zinc sulfate an aliquot of 0.1 M zinc sulfate in methanol was added to the serum sample in a proportion of 2 1 (v/v) to serum. Analytes were extracted by a short pentafluorophenyl silica column and separated on a longer analytical column with the same stationary phase. Recoveries of all analytes were above 80 %. The proposed procedure by Matuszewski et al. [64] was used for the evaluation of matrix effect ME(%)=B/Ax 100, where ME is the matrix effect (suppression or enhancement) and B corresponds to peak areas for standards spiked after extraction into sample extracts and A to peak areas obtained in neat solution standards. Authors compared this method to offline SPE coupled with GC-MS and results showed that LC-MS/... 

C.E. Kientz, E.W.J. Hooijschuur and U.A.Th. Brinkman, Capillary electrophoresis coupled online with flame photometric detection determination of alkylphosphonic acids, J. Microcol. Sep., 9, 253-259 (1997). 

E.W.J. Hooijschuur, Ch.E. Kientz, A.G. Hulst and U.A.Th. Brinkman, Determination of hydrolysis products of sulfur mustards by reversed-phase microcolumn liquid chromatography coupled online with sulfur flame photometric detection and electrospray ionization mass spectrometry using large-volume injections and peak compression, Anal Chem., 72, 1199-1206 (2000). 

Hassellov, M., Lyven, B., and Beckett, R., Sedimentation field-flow fractionation coupled online to inductively coupled plasma mass spectrometry New possibilities for studies of trace metal adsorption onto natural colloids, Environ. Sci. Technol., 33, 4528-, 1999. 

MALDI and ESI represent the predominant ionization techniques in mass spectrometry-based proteomics, as recognized by the Nobel Prize in chemistry in 2002. MALDI is mainly used to volatize and ionize simple polypeptide samples for mass spectrometric (MS) analysis at high speed. The analysis of more complex peptide mixtures is usually conducted via ESI mass spectrometry (ESI MS) coupled online with a high-pressure liquid chromatography (HPLC) system to concentrate and separate peptides prior to MS analysis. 

If a protein spot cannot successfully be identified by MALDl analysis, peptide sequencing byautomated nano HPLC/FSI MS/MS is an alternative. This provides superior sensitivity due to the preconcentration of peptides on trapping columns (Mitulovic et ah, 2003) and delivers considerably more sequence-specific information at the peptide level. However, nano HPLC coupled online with ESI-tandem MS analysis is much more time-consuming than MALDI-PMF. Therefore, it is predominantly used to efficiently identify complex protein samples which have only been separated partially, e.g., by 1-D PAGE. This case represents the... 

Grell GA, Peckham SE, Schmitz R, McKeen SA, Frost G, Skamarock WC, Eder B (2005) Fully coupled online chemistry within the WRF model. Atmos Environ 39(37) 6957-6975... 

Fig. (1). Peptidomics strategies used to study Drosophila immunity. (A) Using antimicrobial assays (antibacterial and antifungal), the bioactive peptides were isolated from the blood of bacteria-challenged Drosophila. MS was used for molecular mass assignment, to identify post-translational modifications, and for primary structure elucidation (B) Identification of peptidic immune effectors through differential display analysis (DD) by MALDI-MS and micro/nano RP-HPLC coupled (online) or not (off-line) to ESI-MS. When the HPLC was performed off-line to the mass spectrometer, fractions were individually analyzed by MALDI-MS. The identification and the structural characterization were performed either by molecular mass assignment and/or sequencing by ESI-MS/MS.

Capillary Electrophoresis (CE) and Micellar Electrokinetic Chromatography (MEKC). - Di(2-ethylhexyl) thiophosphoric acid (DEHTPA) has been earlier characterised by potentiometric titration, and quantified by capillary zone electrophoresis with carbonate buffer, operating at —20 kV, and using UV detection at 210 nm. ° Also, a comparison has been made of capillary electrophoresis (CE) and liquid chromatography (LC) for the enantiomeric separation of a-phosphonosulfonic acids, where CE used 3-cyclodextrin as chiral selector in a borate electrolyte. Alkylphosphonic acids, at trace levels in water, have been determined by CE coupled online with flame photomeric detection, and alkylphosphonic acid esters have been separated and determined by CE using indirect UV detection. 

A.J.J. Debets, W.T. Kok, K.P. Hupe, U.A.T. Brinkman, Electrodialytic sample treatment coupled online with high-performance liquid chromatography, Chromatographia 30 (1990) 361. 

Ericsson, M. and Colmsjo, A., Dynamic microwave-assisted extraction coupled online with SPE and large-volume injection gas chromatography determination of organophosphate esters in air samples. Anal. Chem., 75, 1713-1719, 2003. 

---