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The article focuses on the sensibility of the method requirements for liquid chromatography (LC). It mentions that peak tailing is an important problem with the method in which adequate buffering is a significant component. It notes that one has to balance the cost of the method changes and revalidation against the cost of method transfer .

Run a difficult food sample on your IC and you stand a big chance that you will wreck the column. Of course, you can waste a lot of time on tedious sample preparation steps to eliminate undesired matrix components. Or you can go for Metrohm's automated compact stopped-flow dialysis providing optimum separation while protecting your column from detrimental compounds. [ABSTRACT FROM AUTHOR]

The article explores a problem related to the transfer of a method from one instrument to another in chromatographic analysis. It discusses how to troubleshoot this liquid chromatography (LC) problem. It suggests that a periodic system performance qualification test be performed for each LC system on a semiannual or annual basis so that method transfer problems will not occur.

The article discusses various topics related to ion-pair separations in reversed phase liquid chromatography. It has been noted by the author, that the ion-pair process the mobile phase can be described as the result in a neutral ion pairing between the sample molecule and the reagent. In addition, the ion-pair can be retained as a neutral form in the standard reversed-phase manner.

Countercurrent chromatography (CCC) is experiencing a renaissance and offers a variety of benefits for preparative chromatography. This technique is useful for the isolation of natural products and can eliminate some of the problems associated with solid-phase adsorbents. [ABSTRACT FROM AUTHOR]

The article discusses the impact of flow rate change on the analysis of a multivitamin product using gradient elution with a reversed-phase liquid chromatography separation. It focuses on the possible reasons the retention times could have changed. It attempts to evaluate the influence of flow-rate and the allowable changes specifically for gradient methods. It is concluded that the change in flow-rate has a potential to change peak spacing.

The article discusses the method development for liquid chromatography with an emphasis on developing trouble-free methods. It is noted that the use of retention mapping in method development can greatly speed-up the development process. It is explained that retention mapping can help quickly identify the best conditions for the separation and for daner regions to avoid.

Discusses the use of the retention time of a peak in a liquid chromatography separation as a diagnostic tool to identify problems with a separation. Reduction in the flow-rate of the mobile phase; Increase of the retention time of all peaks that are eluted after the bubble; Minimization of bubble problems.

This article presents information on several products related to chromatography. Phenomenex Inc. has produced an application note demonstrating how a simple reversed-phase HPLC method can be used for both purification and analysis of crude synthesized oligonucleotides in less than 30 minutes. From method development to preparative separations, the SuperPure 50 and 200 are the latest SFC/HPLC products from Thar Technologies Inc. Applications using the PSS HighSpeed family of columns from PSS Polymer Standards Service permit reductions in GPC analysis time for polymers >2000 D without loss in resolution, accuracy or reproducibility.

Discusses the extracolumn effects on the chromatogram's appearance. Advantages of checking for reasonable chromatographic behavior; Importance of controlling temperature and checking its influence on the separation; Retention factor for the analyte in the liquid chromatography assay.

The article focuses on use of the Agilent 1290 Infinity II Method Development Solution with Agilent Method Scouting Wizard for direct development of analytical separation methods under ISET control for a chosen target system. It mentions that results showed correlation between method developed on the Agilent 1290 Infinity and the target system. It also highlights method transfer by direct emulation of different target high performance liquid chromatography (HPLC) systems.

The article focuses on the Martin Gold Medal and the Silver Jubilee Medal from The Chromatographic Society (ChromSoc). It mentions that the Martin Gold Medal is given to scientists who have contributed to the advancement of separation science while the Jubilee Silver Medal is given to younger scientists who used separation science or scientists who contributed to the field. A table is presented which lists the award winners from 2006-2016 including Jim Waters, Peter Myers, and Ronald E. Majors.

The first meeting in The Chromatographic Society's diamond anniversary year brought together world-renowned speakers alongside past presidents of the Society, delegates from academia and industry, and scientific instrument and technology companies at the Institute of Engineering and Technology in central London on 22 March 2016. The presentations included discussions on liquid chromatography (LC), supercritical fluid chromatography (SFC), and gas chromatography (GC) from both an academic and industrial perspective - providing excellent insight into the state-of-the-art in these techniques for the delegates. [ABSTRACT FROM AUTHOR]

The article offers the author's insights regarding the Chromatographic Society (ChromSoc) which focuses on gas chromatography (GC). Topics include the meeting of the organization in London, England about the growth in GC, the impact of separation science in the industry and on the quality of everything, and the benefits GC and liquid chromatograhy (LC).

Hydrophilic interaction liquid chromatography (HILIC) offers unique advantages for the separation of very polar compounds when compared to reversed-phase chromatography. A new silica based HILIC phase was developed to provide additional selectivity options in HILIC separations, The separation of water soluble vitamins on the new TSKgel NH2-1OO HIUC column and on the well known TSKgel Amide-80 HILIC column demonstrates the differences in selectivity. [ABSTRACT FROM AUTHOR]

The article focuses on the Shim-pack MAYI-ODS pretreatment column, which is used in an on-line sample pretreatment of biological samples. It selectively excludes macromolecules such as proteins and effectively traps drugs and other low-molecular compounds. Diagrams detailing the phase capacity of Shim-pack MAYI-ODS are presented.

The article discusses ways on using the gradient scouting run to speed the isocratic method for phase separation. The first thing to do is to run the scouting run and examine if it is suitable for the sample. Then, determine the isocratic conditions using the Excel spreadsheet calculator. After the scouting gradient has been run and the isocratic conditions have been determined to be appropriate, one can make the first isocratic run.

The article offers information on how to scale the UltraPerformance liquid chromatography (UPLC) impurity/degradant separation to a preparative LC separation. The UPLC separation of the ranitidine degradation sample succeeds because it was found that ranitidine is resolved from all other compounds in the mixture. Moreover, further optimization can be achieved by simple modification of the gradient profile.

A single chromatographic method was developed for the analysis of common formulation compositions targeted to relieve symptoms associated with the common cold using a new high strength silica (HSS) UPLC stationary phase. [ABSTRACT FROM AUTHOR]

The article discusses the Kromasil CelluCoat which performs in all areas of chiral chromatography. Kromasil CelluCoat is considered good choice for analytical separations for preparative enantiomer purification both in laboratories and in scale production. It is also available in particle size packed of stainless steel column and bulk materials.

The article focuses on the impact of the size of pore packing materials for peptide separations in ultra performance liquid chromatography peptide mapping. The pore size materials of 130 A and 300 A are compared in the separation of its two complex peptide digests. The result shows that both peptide separation technology columns give useful separations of peptides over a wide range of sizes and chemical properties.

The article outlines a technique of improving separations by transferring methods from High Performance Liquid Chromatography (HPLC) to Ultra Performance Liquid Chromatography (UPLC). UPLC has significant advantages over HPLC in terms of speed, sensitivity and resolution. Transfer of a method for the separation of caffeic acid derivatives from echinacea purpurea from HPLC to UPLC is described.

The article discusses on the use of tetrabutylammonium bromide and tetrahexylammonium bromide reagents and Amberchrom HPR10, a 10 micron, mono-sized, reversed phase polymeric resin, in oligonucleotides separation. All analyses are performed on an Agilent 1100 High Performance Liquid Chromatography system using a Dionex NucleoPac PA-100 column.

Describes the role of SunFire Intelligent Speed high performance liquid chromatography in enabling high-throughput liquid chromatography (LC) and LC/mass spectrometry separations. Details on the preferential retention of hydrogen-bond donors; Provision of unique and specific selectivity with aromatic compounds; Availability of bonded phases for methods development.

Describes the use of ultra performance liquid chromatography (UPLC) in providing flexibility for developing separations. Compatibility between chemistry and instrumentation; Details on the efficiency of the UPLC columns; Improvements in resolution, sensitivity and sample throughput.

Describes the use of the liquid chromatography-mass spectrometry as a tool for the characterization of proteins. Efficacy of the separation technique as an approach for the desalting of proteins; Importance of the separation of proteins from non-volatile salts as a step prior to introduction into the mass spectrometer; Determination of loading capacity of monoclonal immunoglobulin G.

Describes the use of a polymeric reversed-phase packing material Amberchrom HPR10 for the purification of recombinant human insulin. Application of ion-pairing agents in reversed-phase chromatography; Effect of mobile phase composition on reversed-phase separations; Conduction of purification with and without the addition of a neutral salt in the mobile phase.

Column lifetime is a more and more important issue when developing an analytical method for HPLC. Beside sample treatment, column cleaning and storage, operational parameters of the analytical method will have an influence on column lifetime. This question may not always be addressed early enough in the methods development process. [ABSTRACT FROM AUTHOR]

The article focuses on mass spectrometric detection of homocysteine, methylmalonic acid and succinic acid using HILIC on a zwitterionic stationary phase. The HILIC columns are silica based stationary phases with either 3.5, 5 or 10 pm particle size, while the pHILIC columns are polymer-based stationary phases with 5 fjm particle size, yet both having a sulfobetaine type zwitterionic functionality. The article concludes that the HILIC column is indeed a suitable tool for separation of homocysteine, methylmalonic acid and succinic acid. Combined with MS detection, physiological relevant concentration can easily be quantified with the possibility of processing up to 20 samples per hour.

The article focuses on the determination of allergens in fragrance products. The determination of 24 allergens in cosmetic products has become an important issue because of the procedure described by the International Fragrance Association. Where fragrance products such as perfumes can be diluted and measured with GC/MS directly, products such as creams and lipsticks need preparation. Fast GCMS by using narrow-bore columns has become a reliable routine tool by maintaining most of the chromatographic resolution.

The article presents a new device for high-resolution separations of oligonucleotides. The DNAPac® PA200 is a new high-efficiency, strong anion- exchange column with enhanced stability under alkaline conditions. Strong anion-exchange chromatography, using pH -stable polymeric resins, is a simple and effective technique for separating oligonucleotides. The DNAPac® PA200 employs a new monomer that improves phase stability under alkaline conditions and offers improved peak width, peak capacity, and resolution.

The article presents information about hydrophilic interaction liquid chromatography (HILIC) as a means of separating polar and hydrophilic compounds. This technique is orthogonal to reverse-phase chromatography. The separation mode in HILIC uses an eluent containing a high content of water miscible organic solvent to promote hydrophilic interactions between the analyte and water wetted hydrophilic stationary phase. ZIC ® -HILIC Phase is one of the best HLIC Phases commercially available.

The article presents information about Intelligent Speed (IS™ high performance liquid chromatography columns. Nowadays, dosage forms are more complex due to multiple active ingredients in various types of excipient matrices. These complex dosage forms require the use of an advanced, automated dissolution system to improve productivity and efficiency. Use of Intelligent Speed (IS™ high performance liquid chromatography columns with Alliance® Dissolution System can decrease overall analysis time.

The article presents information about SunFire™ C18 reversed-phase high performance liquid chromatography columns. These columns provide high efficiencies and symmetric peak shapes for the analysis of acids, neutrals and bases and they exhibit superior lifetimes under low pH conditions.

The article presents information about analysis of molecular weight and structure of polymers used in controlled drug delivery systems. Analysis of the raw polymers and the polymer-drug bioconjugates is critical to both the development and production of the materials. Gel permeation chromatography (GPC or SEC) is commonly used for the analysis of many synthetic and natural polymers including proteins. Triple Detection GPC system can give the true molecular weight of any drug delivery polymer directly, without relying on comparison with standards.

The article discusses the effectiveness of embedded polar group(EPG) columns in retention of polar analytes in comparison with Atlantis™ dC18 reversed-phase high performance liquid chromatography columns. Experiments conducted by the manufacturers show that EPG columns exhibit less retention for polar compounds as compared to Atlantis™ dC18 reversed-phase high performance liquid chromatography columns.

The article presents the reversed-phase antibody separation process using Jupiter™ 300 C4 High Performance Liquid Chromatography (HDLC) Columns. Antibodies have often proved difficult to analyse by reversed-phase chromatography due to their large size and moderate hydrophobicity. Experiments have demonstrated the ability of Jupiter™ 300 C4 columns to resolve differences between large hydrophobic proteins for the purposes such as separation of immunoglobulin proteins.

Hydrophilic interaction liquid chromatography (HILIC) is a separation technique suitable for polar and hydrophilic compounds, and is orthogonal to reversed-phase chromatography. The separation mode uses an eluent containing a high content of water miscible organic solvent to promote hydrophilic interactions between the analyte and a water wetted hydrophilic stationary phase, and is thus a technique comparable, in principle, to traditional normal-phase chromatography. This article presents an example of an isocratic HILIC separation of purines and pyrimidines.

Synthetic fused silica capillary tubing continues to be the material of choice for modern Gas Chromatography (GC) columns. In this application note, we examine dimensional specifications of GC tubing from a historical perspective and compare It to empirical data from current production runs. [ABSTRACT FROM AUTHOR]

Features several literature on separation science. Dionex Corp.'s product catalogue on CD-ROM; Bionisis' application bulletin describing how scientists can monitor the metabolism of radioactively labelled drug candidates; Sun-Sri's catalogue for its range of chromatography vials and validated syringe filters.

Reports on issues related to the use of high-performance liquid chromatography (HPLC) in Milford, Massachusetts. Efforts of chemists to increase productivity and reduce laboratory costs; Development of a new method that would reduce the overall runtime of separation; Theory behind fast gradient separations.

Describes a method for faster separations in high-performance liquid chromatography that offers higher throughput and reduced costs. Traditional approaches to fast separations; Column hardware; Theory behind fast gradient separations; Scaling separations for increased throughput and reduced costs.

Demonstrates the utility of Atlantis dC[sub 18] columns via the separation and purification of three mixtures of polar compounds. Experimental conditions; Description of Atlantis dC[sub 18] reversed-phase columns; Retention and separation of the sulphonamides on the analytical column.

Discusses the separation of peptides by hydrophilic interaction chromatography using the TSKgel Amide-80 column, a method developed by Tosoh Bioscience GmbH that provides excellent selectivity for separating peptides in hydrophilic interaction chromatography. Overview of methods for the separation of peptides with many acidic and basic residues; Effect of acetonitrile concentration on peptide retention.

Describes the use of the multiOPLC system, an Optimum Performance Laminar Chromatography system that incorporates the Flowing Eluent Wall Technology, to perform simultaneous semi-preparative scale separations of complex samples. Reagents and separation media; Instrumentation; Capability of the system to produce four independent channels on an unsegmented flat-bed column.

A calendar of events for August to October 2013 is presented, which include the Euroanalysis conference in Poland, the 9th Balaton Symposium on High-Performance Separation Methods in Hungary, and the 19th International Symposium on Separation Sciences in Croatia.

A calendar of congresses and symposiums related to chromatography from July 1 to October 9, 2013 is presented including the 9th annual conference of the Metabolomics Society in Glasgow, Scotland from July 1-4, the Euroanalysis event of the Polish Chemical Society in Warsaw, Poland from August 25-29, and the 19th International Symposium on Separation Sciences in Porec, Croatia from September 25-28.

A calendar of events from March to June 2011 in the U.S. is presented which includes Arablab Conference, sixth International MS and Related Techniques Symposium and VII International Ion Chromatography Conference.

The article offers information on CHROMacademy, an e-learning programme on chromatography. The web site offers chromatography training for the professional development of chromatographers in which it assists them on separation techniques, parameter optimization, and troubleshooting separations. It notes that the web site will launch a 3D interactive high performance liquid chromatography (HPLC) Troubleshooter that assists on chromatographic troubleshooting.

The article describes the use of gel permeation chromatography (GPC) method for the determination of molecular weight distribution in the polyacrylonitrile (PAN) samples. The analysis employs a moderately polar column and polar mobile phase and the separation was performed in isocratic mode on a KNAUER Smartline high performance liquid chromatography (HPLC) system. It was observed that the PAN sample's molecular weight were within the linear calibration range.