Working with biological fluids poses a challenge of visualizing proteins present in lower concentrations. This study describes a batch-mode chromatographic method for the fractionation of human amniotic fluid (AF). This method is easy to use with minimal sample quantity, resin volume and sample processing time. For albumin depletion, two methods were evaluated. The results demonstrated that specific depletion of albumin, using affinity-ligand-based resin, is more efficient than the conventional dye-based method. The albumin-depleted human AF was fractionated by strong anion-exchange resin in spin devices, for sample, complexity reduction and enrichment of low-abundant proteins. Analysis of four eluate fractions generated after this step shows enrichment of few low-abundant proteins. Two novel low-abundant proteins, Rab GDP dissociation inhibitor beta and peptide methionine sulfoxide reductase, were identified from human AF. Alpha-1-B glycoprotein was successfully identified by this strategy, whereas the published literature reports that it was not identified by strong anion-exchange FPLC followed by SDS-PAGE. Therefore, the current method has distinct advantages over the conventional column-based chromatography. This study also reports altered expression of some proteins in Rh-isoimmunized AF samples in comparison with normal AF.

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This article was originally published in Journal of Separation Science 2010, 33, 1723–1729, DOI

There is an urge for traditional herbal remedies as an alternative to modern medicine in treating several ailments. Alangium salviifolium is one such plant, used traditionally to treat several diseases. In several reports, there are findings related to the use of this plant extract that demonstrate its therapeutic value. However, very few attempts have been made to identify the extensive metabolite composition of this plant. Here, we performed metabolite profiling and identification from the bark of A. salviifolium by extracting the sample in organic and aqueous solvents. The organic and aqueous extracts were fraction-collected using the Agilent 1260 Analytical Scale Fraction Collection System. Each of the fractions was analyzed on Liquid Chromatogaphy/Quadrupole Time-of-Flight LC/Q-TOF and Gas Chromatography/Quadrupole Time-of-Flight GC/instruments. The Liquid Chromatography/Mass Spectrometry (LC/MS) analyses were performed using Hydrophilic Ineraction Liquid Chromatography (HILIC), as well as reversed-phase chromatography using three separate, orthogonal reverse phase columns. Samples were analyzed using an Agilent Jet Stream (AJS) source in both positive and negative ionization modes. The compounds found were flavonoids, fatty acids, sugars, and terpenes. Eighty-one secondary metabolites were identified as having therapeutic potential. The data produced was against the METLIN database using accurate mass and/or MS/MS library matching. Compounds from Alangium that could not be identified by database or library matching were subsequently searched against the ChemSpider) database of over 30 million structures using MSMS data and Agilent MSC software.In order to identify compounds generated by GC/MS, the data were searched against the AgilentFiehn GCMS Metabolomics Library as well as the Wiley/NIST libraries.

Bioinformatics tools to aid gene and protein sequence analysis have become an integral part of biology in the post-genomic era. Release of the Plasmodium falciparum genome sequence has allowed biologists to define the gene and the predicted protein content as well as their sequences in the parasite. Using pI and molecular weight as characteristics unique to each protein, we have developed a bioinformatics tool to aid identification of proteins from Plasmodium falciparum. The tool makes use of a Virtual 2-DE generated by plotting all of the proteins from the Plasmodium database on a pI versus molecular weight scale. Proteins are identified by comparing the position of migration of desired protein spots from an experimental 2-DE and that on a virtual 2-DE. The procedure has been automated in the form of user-friendly software called "Plasmo2D". The tool can be downloaded from http://144.16.89.25/Plasmo2D.zip.