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The oxygenation of hemoglobin is under the control of the regulatory function of organic phosphates. The one in mammals corresponds to 2,3-bisphosphoglyccrate but in birds and turtles appears to be inositol hexakisphosphate. The latter component decreases the oxygen affinity of the two chicken hemoglobin compounds (the minor and the major) and the lone pigeon hemoglobin component. The Bohr effects have also been determined for the two hemoglobin samples. As has already been observed by electrophoresis and by chromatography, pigeon hemoglobin seems to behave more like that of the major chicken component by disclosing analogous log P50 values, i.e. the partial pressure of oxygen corresponding to a 50% load of the hemoglobin. [ABSTRACT FROM AUTHOR]

Tyrosinase was dissolved from the melanosome fraction of Harding-Passey mouse melanoma and purified further by Sephadex G-100 gel filtration and DEAE-cellulose column chromatography. The specific activity of the purified preparation was 763 times as high as that of the original melanosome. Tyrosinase thus isolated showed only a single activity in both the electrophoresis of a polyacrylamide gel and a cellulose acetate. The Km value is the same as those of the original melanosome and the smooth-surfaced-membrane. The relationship between particle bound tyrosinase and solubilized tyrosinase is discussed in this paper. [ABSTRACT FROM AUTHOR]

This article discusses the characterization of fountain pen inks by porous glass chromatography and electrophoresis. Identification of fountain pen inks and writing fluids has long been a subject of considerable interest to the examiner of questioned documents. In order to accurately identify the various ink formulations that are commercially available, many techniques using a variety of analytical procedures have been developed. Of these, perhaps the most accepted method in current usage is that of paper chromatography. This separation method allows the various ink components, many of which are colored dye substances, to be separated into integral bands or zones that distribute themselves in a manner characteristic of the original combined formulation. In an effort to overcome many of the inherent difficulties associated with paper as a chromatographic or electrophoretic medium, it was conceived that porous glass might offer properties which would permit such separations under a wider range of conditions. In addition, the final separations would be in a medium which was itself optically transparent. This unique glass was obtained and found to be quite acceptable for these applications.

The article discusses the bioanalytical methods used in the Bachelor of Science (BSc) analytical chemistry curriculum. It explains the goal of analytical chemistry course, along with an overview of the basic BSc analytical chemistry curriculum. The bioanalytical methods that were found to be included in analytical chemistry curriculum are enzymatic methods, immunoanalytical methods and the separation of biomacromolecules by electrophoresis and chromatography.

Objective: To determine whether dimethylmethylene blue (DMMB) analysis, when combined with agarose gel filtration chromatography (Superose 6), can be performed instead of fluorophore-assisted carbohydrate electrophoresis (FACE) to determine chondroitin sulfate (CS) chain length in synovial fluid (SF).Methods: SF was obtained from (1) normal horses after 8 weeks of rest, (2) the same horses after 9 months of treadmill training, and (3) horses with osteochondral (OC) injury from racing. SF CS concentrations and chain lengths were determined by gel chromatography and DMMB analysis and compared with previous results determined by FACE analysis on the same samples.Results: DMMB analysis showed that SF CS peak chain length in the OC injury group increased significantly (18.7 kDa) when compared to rested and exercised normal horses (15.6 kDa). The assay had a positive predictive value of 71% and a negative predictive value of 75% for discriminating between normal and injured joints.Conclusions: We report a simple and inexpensive DMMB analysis of SF CS chain length, which, when coupled with Superose 6 chromatography, discriminates between normal and post-injury joints. Similar to our previous FACE analysis results [Brown MP, Trumble TN, Plaas AHK, Sandy JD, Romano M, Hernandez J, et-al. Exercise and injury increase chondroitin sulfate chain length and decrease hyaluronan chain length in synovial fluid. Osteoarthritis Cartilage 2007;15], our DMMB results show an increase in the chain length of the CS in the SF of injured joints. [ABSTRACT FROM AUTHOR]

Information about several lectures discussed at a meeting of ExTech and HTC-9 is presented. The meetings were organized by the chairperson Robert Smits of Royal Flemish Chemical Society and chairperson Tom Lynch of Chromatography and Electrophoresis Group. However, in the meeting of Extech, the speakers discussed the increased automation. While, in the HTC-9 meeting, the lecturer described the task in monitoring endocrine disrupting chemicals.

From the lipopolysaccharide of the gram-negative bacterium Rhodopseudomonas capsulata (Athiorhodaceae) a lipophilic sugar was isolated by chromatographic procedures and characterized by mass spectrometry as belonging to the group of 3-O-methyl-6-deoxy-hexoses. Demethylation showed that the parental sugar had the same properties in borate electrophoresis as rhamnose. Comparison with an authentic sample of 3-O-methyl-rhamnose in gas liquid chromatography, paper chromatography and borate electrophoresis showed that the sugar under examination is 3-O-methylrhamnose (acofriose). Investigation of its optical rotation indicates that the sugar has the L-configuration. L-Acofriose (3-O-methyl-L-rhamnose) has not hitherto been found in lipopolysaccharides of gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Summary: Chromaligner is a tool for chromatogram alignment to align retention time for chromatographic methods coupled to spectrophotometers such as high performance liquid chromatography and capillary electrophoresis for metabolomics works. Chromaligner resolves peak shifts by a constrained chromatogram alignment. For a collection of chromatograms and a set of defined peaks, Chromaligner aligns the chromatograms on defined peaks using correlation warping (COW). Chromaligner is faster than the original COW algorithm by k2 times, where k is the number of defined peaks in a chromatogram. It also provides alignments based on known component peaks to reach the best results for further chemometric analysis. [ABSTRACT FROM PUBLISHER]

Prematurity may be associated with so-called F-only status that interferes with early diagnosis of hemoglobinopathies and thalassemias. We present the case of a 4-week-old, prematurely born (at 31 weeks, 3 days) African American boy whose blood shows exclusively hemoglobin F on alkaline and acid electrophoresis. Meanwhile, high-performance liquid chromatography testing revealed the presence of trace amounts of hemoglobin A and S, which prompted the correct diagnosis and suggested further patient follow-up. This demonstrates the superior analytical sensitivity of high-performance liquid chromatography in detecting trace amounts of hemoglobin A and S that is helpful in the early diagnostic process. [ABSTRACT FROM AUTHOR]

In recent decades, xylanases have been used in many processing industries. This study describes the xylanase production by Penicillium glabrum using brewer's spent grain as substrate. Additionally, this is the first work that reports the purification and characterization of a xylanase using this agroindustrial waste. Optimal production was obtained when P. glabrum was grown in liquid medium in pH 5.5, at 25 °C, under stationary condition for six days. The xylanase from P. glabrum was purified to homogeneity by a rapid and inexpensive procedure, using ammonium sulfate fractionation and molecular exclusion chromatography. SDS-PAGE analysis revealed one band with estimated molecular mass of 18.36 kDa. The optimum activity was observed at 60 °C, in pH 3.0. The enzyme was very stable at 50 °C, and high pH stability was verified from pH 2.5 to 5.0. The ion Mn(2+) and the reducing agents ß -mercaptoethanol and DTT enhanced xylanase activity, while the ions Hg(2+), Zn(2+), and Cu(2+) as well as the detergent SDS were strong inhibitors of the enzyme. The use of brewer's spent grain as substrate for xylanase production cannot only add value and decrease the amount of this waste but also reduce the xylanase production cost. [ABSTRACT FROM AUTHOR]

Amino acids (AA) are essential nutritional components of a balanced diet and occur in foods in either the free AA form or as the building blocks of proteins. The analysis of AAs in foods is composed of a number of unit operations; the release of the AAs from the food matrix, the separation of the individual AAs and their quantification using calibration standards. Each of these steps has their own idiosyncrasies, e.g. different hydrolysis conditions are required for the optimal release of different AAs and there are a diverse number and type of food matrices, such that most laboratories adapt methods to best suit their applications. There is currently no official standardised method for AA analysis, although the Association of Analytical Communities (AOAC) has validated methods for a number of individual AA components. The established analytical techniques of HPLC (ion exchange or reversed phase) and GC-MS have recently been supplemented by a number of new methods. These include capillary electrophoresis MS and Ultra HPLC-MS, and LC with other detectors. This review will address the intricacies and concerns of the protein hydrolysis step, discuss what specifications or prerequisites need to be placed on the existing and new methods and laboratories using these methods, comment on whether one method can successfully satisfy the exacting requirements of the various unit operations, and finally pose the question ‘Is there any merit in ‘developing’ a validated (e.g. AOAC) official method of analysis for AAs in food?’ [ABSTRACT FROM PUBLISHER]

The lipooligosaccharide (LOS) of Neisseria meningitidis contains heptose (Hep) residues that are modified with phosphoethanolamine (PEtn) at the 3 (3-PEtn) and/or 6 (6-PEtn) position. The lpt3 (NMB2010) and lpt6 (NMA0408) genes of N. meningitidis, which are proposed to encode the required HepII 3- and 6-PEtn transferases, respectively, were cloned and overexpressed as C-terminally polyhistidine-tagged fusion proteins in Escherichia coli and found to localize to the inner membrane, based on sucrose density gradient centrifugation. Lpt3-His6 and Lpt6-His6 were purified from Triton X-100-solubilized membranes by nickel chelation chromatography, and dot blot analysis of enzymatic reactions with 3-PEtn- and 6-PEtn-specific monoclonal antibodies demonstrated conclusively that Lpt3 and Lpt6 are phosphatidylethanolamine-dependent LOS HepII 3- and 6-PEtn transferases, respectively, and that both enzymes are capable of transferring PEtn to both fully acylated LOS and de-O-acylated (de-O-Ac) LOS. Further enzymatic studies using capillary electrophoresis-mass spectrometry (MS) demonstrated that both Lpt3 and Lpt6 are capable of transferring PEtn to de-O-Ac LOS molecules already containing PEtn at the 6 and 3 positions of HepII, respectively, demonstrating that there is no obligate order of PEtn addition in the generation of 3,6-di-PEtn LOS moieties in vitro. [ABSTRACT FROM AUTHOR]

This article focuses on a calendar of events related to chromatography. Some of the events are: The 8th MipTec international conference and exhibition on drug discovery takes place at the Basel Convention Center from 9-12 May, 2005. The topics include: pre-clinical profiling and biomarker discovery " leveraging the power of informatics in drug discovery, orphan target identification and validation, structure-based drug discovery and chemical genomics. Another event is 28th International Symposium on Capillary Chromatography and Electrophoresis Las Vegas, Nevada, U.S.A.

The Royal Society of Chemistry's Analytical Division Chromatography and Electrophoresis Group and the North East Region Analytical Division are Organizing a two-day symposium and exhibition reflecting upon the last 100 years of separation science. "A Century of Separation Science--Celebrating the Past: Predicting the Future" takes place at Le Meridien Hotel Conference Centre, York on April 1-2, 2004. The event is sponsored by Agilent Technologies and Waters together with The Chromatographic Society, Anatune, Applied Automation, Cohesive Technologies Inc., Dionex Corp., Greyhound Chromatography, etc.